The ever-accelerating expansion of the universe may be driven by a mysterious form of matter called "unparticles," which do not obey the Standard Model of particle physics, a new theoretical paper suggests.

Scientists widely acknowledge that the universe is expanding, though the cause of that expansion remains elusive. One of the most popular proposed explanations is a mysterious entity called dark energy in the form of a cosmological constant, which leads to expansion at a rate independent of the age of the universe and the temperature of matter and radiation. However, recent astronomical observations challenge this hypothesis, prompting physicists to explore alternatives to what dark energy could be.

Now, in a new paper, researchers analyzed the idea that dark energy is instead made of a theoretical form of matter called unparticles. They found that this theory aligns better with observations than the prevalent standard cosmological model, which assumes a cosmological constant.

Related: James Webb Space Telescope complicates expanding universe paradox by checking Hubble's work

"Observationally, discrepancies arise in the values of the universe's expansion rate and the growth of large-scale structures [galaxies and galactic clusters] between measurements," study co-author Utkarsh Kumar, a cosmologist at Ariel University, told Live Science in an email. "Various observations, including Cosmic Microwave Background measurements, dimming of supernovae and many others, contribute to this tension."

Quantities such as the Hubble constant, which determines the rate of expansion, and the so-called S8, which contains information about the formation of large-scale structures, are not measured directly. Instead, they are calculated from observations of the cosmic microwave background (leftover radiation from the Big Bang) and distant stars and galaxies, using mathematical  theories. However, different theories yield different values of these parameters from the same data, posing a huge tension in cosmology.

To address this problem, the authors of the new study, published in December 2023 in the Journal of Cosmology and Astroparticle Physics, suggest that the expansion of the universe is driven not by a cosmological constant but by unparticles, which had previously been considered in the context of particle physics.

"The idea of unparticles was introduced by [theoretical physicist Howard] Georgi over a decade ago," lead study author Ido Ben-Dayan, also of Ariel University, told Live Science in an email. "In fundamental physics, we usually discuss fields, like the electric field, where particles are excitations of that field. In the electric field case, these are the photons," or packets of light. In almost all cases, Ben-Dayan added, particles are excitations with a well-defined mass and momentum.

However, "unparticles are the result of a set of fields that their excitations do not have a well-defined momentum and mass," Ben-Dayan said. "Thus, at the macroscopic level, they behave as a fluid. A special outcome of this property is that their equation of state, describing the ratio between the pressure they exert and their energy density, depends on temperature."

This equation of state strongly resembles the equation for the cosmological constant. Moreover, the very weak interaction of unparticles with “regular” matter, which is predicted by all theoretical models of the substance, makes it an excellent candidate for dark energy.

Unparticles untangled

In their work, Ben-Dayan and Kumar used the unparticle hypothesis instead of the cosmological constant and combined it with observational data collected from many experiments. They found that, unlike the values calculated using the standard cosmological model, the values of the Hubble constant and the S8 parameter deduced from these experiments were consistent with each other when they used the unparticle theory.

"Moreover, their model reduced the discrepancy between the measurements of the Hubble constant and S8, thus restoring the agreement between the different measurements, Kumar said. 

For now, there is no empirical evidence to back up this theory.  However, the authors are confident that, in the next decade or so, the accuracy of astronomical measurements will improve enough to determine whether the unparticle theory is correct.

"Our model is tested by constantly improving cosmological observations," Ben-Dayan said. "If it is correct, future Cosmic Microwave Background experiments should [confirm it]."

Experiments to measure the nature of dark energy are currently being developed, but will require telescopes to "probe further back in time" than they currently do, Ben-Dayan added.

Moreover, the physicists plan to increase the accuracy of their calculations and look for possible manifestations of unparticles in more familiar experiments with elementary particles in accelerators, which could be affected by the presence of unparticles.

"We plan to consider interactions between unparticles and the Standard Model of elementary particles," Kumar said. "This can further test our model. We will further study some extensions of our model and their cosmological consequences."

Researchers have proposed a "missing" scientific law for the evolution of life, minerals, planets, stars and pretty much everything else in the universe.

This new law identifies "universal concepts of selection" that drive systems to evolve, whether they're living or not. It addresses the tendency for natural systems in the universe to become more complex over time.

The research team behind the law, which included philosophers, astrobiologists, a theoretical physicist, a mineralogist and a data scientist, have called it "the law of increasing functional information."

"This was a true collaboration between scientists and philosophers to address one of the most profound mysteries of the cosmos: why do complex systems, including life, evolve toward greater functional information over time?" study co-author Jonathan Lunine, a physical science professor at Cornell University, said in a statement.

Lunine and his colleagues described their new law in a study published Oct. 16 in the journal PNAS.

Related: 'Doubly magic' form of oxygen may challenge a fundamental law of physics

Scientific laws are descriptions of observed phenomena. They don't explain why those phenomena exist or what causes them, but they advance our scientific understanding and provide a launching pad for future research.

The new law states that "the functional information of a system will increase (i.e., the system will evolve) if many different configurations of the system undergo selection for one or more functions," the researchers wrote in the study.

The law applies to systems that form from numerous components — such as atoms, molecules and cells — which can be arranged and rearranged repeatedly and adopt multiple different configurations, according to the statement. The law also says these configurations are selected based on function, and only a few survive.

Expanding Darwin's theory of evolution, the researchers claim that non-living systems also evolve when a novel configuration of components works and improves function. One example of a function is stability, according to the statement.

The scientific community is reacting to this new law. Commenting on a statement  from the Carnegie Science Earth and Planets Laboratory in Washington, D.C., theoretical biologist Stuart Kauffman, professor emeritus of biochemistry and biophysics at the University of Pennsylvania, said the study is a "superb, bold, broad, and transformational article," while Milan Cirkovic, a research professor at the Astronomical Observatory of Belgrade, called the study "a breeze of fresh air blowing over the difficult terrain at the trijunction of astrobiology, systems science and evolutionary theory."

However, The Guardian reported that not everyone is quite so taken with the law, including astronomer Martin Rees, professor emeritus of cosmology and astrophysics at the University of Cambridge.

"Given an immense amount of space and time, and the laws of physics and chemistry, an expanding variety of materials, environments and structures will emerge in the inanimate world," Rees said. "But I don’t see that this need be a manifestation of any new underlying principle analogous to the role of Darwinian selection via inheritance in the biological world."

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Valerio Faraoni is a Professor of Physics & Astronomy at Bishop's University. Andrea Giusti is a postdoctoral fellow at the Swiss Federal Institute of Technology Zurich.

Einstein's theory of gravity — general relativity — has been very successful for more than a century. However, it has theoretical shortcomings. This is not surprising: the theory predicts its own failure at spacetime singularities inside black holes — and the Big Bang itself.

Unlike physical theories describing the other three fundamental forces in physics — the electromagnetic and the strong and weak nuclear interactions — the general theory of relativity has only been tested in weak gravity.

Deviations of gravity from general relativity are by no means excluded nor tested everywhere in the universe. And, according to theoretical physicists, deviation must happen.

Related: Was Einstein wrong? The case against space-time theory

Deviations and quantum mechanics

According to Einstein, our universe originated in a Big Bang. Other singularities hide inside black holes: Space and time cease to have meaning there, while quantities such as energy density and pressure become infinite. These signal that Einstein’s theory is failing there and must be replaced with a more fundamental one.

Naively, spacetime singularities should be resolved by quantum mechanics, which apply at very small scales.

Quantum physics relies on two simple ideas: point particles make no sense; and the Heisenberg uncertainty principle, which states that one can never know the value of certain pairs of quantities with absolute precision — for example, the position and velocity of a particle. This is because particles should not be thought of as points but as waves; at small scales they behave as waves of matter.

This is enough to understand that a theory that embraces both general relativity and quantum physics should be free of such pathologies. However, all attempts to blend general relativity and quantum physics necessarily introduce deviations from Einstein’s theory.

Therefore, Einstein’s gravity cannot be the ultimate theory of gravity. Indeed, it was not long after the introduction of general relativity by Einstein in 1915 that Arthur Eddington, best known for verifying this theory in the 1919 solar eclipse, started searching for alternatives just to see how things could be different.

Einstein’s theory has survived all tests to date, accurately predicting various results from the precession of Mercury’s orbit to the existence of gravitational waves. So, where are these deviations from general relativity hiding?

Cosmology matters

A century of research has given us the standard model of cosmology known as the Λ-Cold Dark Matter (ΛCDM) model. Here, Λ stands for either Einstein’s famous cosmological constant or a mysterious dark energy with similar properties.

Dark energy was introduced ad hoc by astronomers to explain the acceleration of the cosmic expansion. Despite fitting cosmological data extremely well until recently, the ΛCDM model is spectacularly incomplete and unsatisfactory from the theoretical point of view.

In the past five years, it has also faced severe observational tensions. The Hubble constant, which determines the age and the distance scale in the universe, can be measured in the early universe using the cosmic microwave background and in the late universe using supernovae as standard candles.

These two measurements give incompatible results. Even more important, the nature of the main ingredients of the ΛCDM model — dark energy, dark matter and the field driving early universe inflation (a very brief period of extremely fast expansion originating the seeds for galaxies and galaxy clusters) — remains a mystery.

From the observational point of view, the most compelling motivation for modified gravity is the acceleration of the universe discovered in 1998 with Type Ia supernovae, whose luminosity is dimmed by this acceleration. The ΛCDM model based on general relativity postulates an extremely exotic dark energy with negative pressure permeating the universe.

Problem is, this dark energy has no physical justification. Its nature is completely unknown, although a plethora of models has been proposed. The proposed alternative to dark energy is a cosmological constant Λ which, according to quantum-mechanical back-of-the-envelope (but questionable) calculations, should be huge.

However, Λ must instead be incredibly fine-tuned to a tiny value to fit the cosmological observations. If dark energy exists, our ignorance of its nature is deeply troubling.

Alternatives to Einstein’s theory

Could it be that troubles arise, instead, from wrongly trying to fit the cosmological observations into general relativity, like fitting a person into a pair of trousers that are too small? That we are observing the first deviations from general relativity while the mysterious dark energy simply does not exist?

This idea, first proposed by researchers at the University of Naples, has gained tremendous popularity while the contending dark energy camp remains vigorous.

How can we tell? Deviations from Einstein gravity are constrained by solar system experiments, the recent observations of gravitational waves and the near-horizon images of black holes.

There is now a large literature on theories of gravity alternative to general relativity, going back to Eddington’s 1923 early investigations. A very popular class of alternatives is the so-called scalar-tensor gravity. It is conceptually very simple since it only introduces one additional ingredient (a scalar field corresponding to the simplest, spinless, particle) to Einstein’s geometric description of gravity.

The consequences of this program, however, are far from trivial. A striking phenomenon is the “chameleon effect,” consisting of the fact that these theories can disguise themselves as general relativity in high-density environments (such as in stars or in the solar system) while deviating strongly from it in the low-density environment of cosmology.

As a result, the extra (gravitational) field is effectively absent in the first type of systems, disguising itself as a chameleon does, and is felt only at the largest (cosmological) scales.

The current situation

Nowadays the spectrum of alternatives to Einstein gravity has widened dramatically. Even adding a single massive scalar excitation (namely, a spin-zero particle) to Einstein gravity —and keeping the resulting equations “simple” to avoid some known fatal instabilities — has resulted in the much wider class of Horndeski theories, and subsequent generalizations.

Theorists have spent the last decade extracting physical consequences from these theories. The recent detections of gravitational waves have provided a way to constrain the physical class of modifications of Einstein gravity allowed.

However, much work still needs to be done, with the hope that future advances in multi-messenger astronomy lead to discovering modifications of general relativity where gravity is extremely strong.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Three scientists have won $100,000 for their work on new ways to study the large-scale structure of the universe — the enormous tendrils of criss-crossing matter which hide evidence of our universe's fundamental forces. 

Mikhail Ivanov, of MIT, Oliver Philcox, of Columbia University and the Simons Foundation, and Marko Simonović, of the University of Florence, won the New Horizons Prize in Physics "for contributions to our understanding of the large-scale structure of the universe and the development of new tools to extract fundamental physics from galaxy surveys."

The New Horizons award is given each year to early career researchers by the Breakthrough Prize Foundation, and the prize money is donated by tech billionaires Sergey Brin, Priscilla Chan and Mark Zuckerberg, Yuri and Julia Milner, and Anne Wojcicki. A second prize was also awarded this year to Alexandru Lupsasca, of Vanderbilt University, and Michael Johnson, of Harvard University for their work chasing mysterious black hole photon spheres.

Related: James Webb Space Telescope reveals active supermassive black holes were surprisingly rare in early universe

Inside the cosmological collider

According to the standard model of cosmology, the universe began taking shape after the Big Bang, when the young cosmos swarmed with particles of both matter and antimatter, which popped into existence only to annihilate each other upon contact. Most of the universe's building blocks wiped themselves out this way. If they had done so completely, no galaxies, stars, or planets would have formed.

Yet the universe was saved by tiny perturbations in the rapidly expanding fabric of space-time, which enabled some pockets of the plasma to survive. As the roiling particle-antiparticle broth of the young cosmos expanded, its molten filaments moved outwards to form an interconnected soap-sud structure of thin films surrounding countless, mostly empty voids.

Today, the universe exists as a map of those earliest particle interactions, which are frozen in time along strands and structures of an enormous cosmic web (today the birthing grounds of galaxies such as our own). This web's form hints at the mysterious, primordial forces that shaped it.

"If you imagine taking the Large Hadron Collider at CERN and scaling it up by a factor of a trillion or a trillion trillions, this is the sort of particle collider that you actually have operating in the early Universe," Oliver Philcox, told Live Science. "And anything weird that happens, it's going to affect the distribution of matter."

Detecting where matter was just after the Big Bang can reveal early particle interactions that occurred during the inflation that followed, a moment when the universe expanded exponentially fast for a mere fraction of a second. If we view the galaxies as the petrified remains of these earliest moments, we can search for hints of particle physics in the super early universe, Philcox said.

"So it is sometimes called the 'cosmological collider' — like a particle collider on the scale of the whole universe," Philcox added.

Until recently, owing to both theoretical as well as experimental limitations, physicists studying how our universe evolved mainly focused on the Cosmic Microwave Background (CMB) — the leftover radiation from the Big Bang that exists as a 2D image burned into every corner of the sky. This can be explained by a simple theorem, only including linear terms, called cosmological perturbation theory.

However, a growing ability to map the universe's cosmic web and a desire to understand mysterious phenomena such as dark matter and dark energy (neither of which are explained by current cosmology) has driven physicists to look at the large scale structures of the web directly.

Dot-mapping a cosmic hurricane

Yet astronomical cartography on these structures enormous is hard. Galaxies are produced by complicated astrophysical processes sculpted by the universe's expansion and the collapse of its matter. 

For instance, when large structures get close to each other, non-linear effects such as virialization (when gravitational objects spiral into a stable orbit) take hold. When they are far away, relativistic effects from the expansion of the universe warp space-time, also disrupting linear equations.

"A good analogy could be water waves. If our universe is an ocean, the CMB fluctuations are tiny ripples on its surface. A galaxy then would be a tsunami, or a hurricane," Mikhail Ivanov told Live Science. "Water ripples can be easily described within basic fluid dynamics developed centuries ago. This is, in essence, cosmological perturbation theory. A hurricane is impossible to describe with pen and paper, we can run some expensive computer simulations for it, but they are highly uncertain."

To skirt these mathematical headwinds, the researchers have been contributing to a theory called effective field theory (EFT) for large scale structures, as well as building several statistical tools that will help them analyze how galaxies interact.

As linear equations to describe the early universe break down at both ends of the cosmic scale, EFT smooths out the picture by simplifying galaxies as dots, and viewing their positions in the cosmos at just the right distance for our two best descriptions of gravity (Newtonian mechanics and general relativity) to be applicable with only minor adjustments. 

Theorists working on EFT have compared this to viewing a Pointillist painting: set the order of magnitude we view the universe at and we see it clearly — not too close for its small-scale chaos, nor too far for relativistic warping.

This has given physicists a powerful new tool with which to view the cosmos, enabling them to make testable predictions about its very earliest beginnings.

"These new ideas can generate new science cases for future galaxy surveys," Marko Simonović told Live Science. "As the new data start arriving in the coming years, it will certainly be very exciting to see what we can learn about our universe beyond what we already know and what surprises are waiting for us along the way."

Humanity's faulty perception of risk has set us on a "spiral of self-destruction," a new United Nations report claims. The report's authors also suggest our future will involve an onslaught of daily disasters by 2030.

The UN's Global Assessment Report, published April 26, highlights some of the doom in store for humanity due to broken perceptions of risk stemming from a trio of thought mistakes: optimism, underestimation and invincibility. 

"By consciously neglecting investment in disaster prevention efforts, while also failing to act with sufficient urgency on related issues like climate change, a broken 'risk perception' can catalyze and compound disasters, causing them to become larger and more impactful than they would have been, had there been sufficient efforts on prevention and risk reduction," Jeanette Elsworth, spokesperson at the UN Office for Disaster Risk Reduction (UNDDR), told Live Science in an email,

These disasters include earthquakes, tsunamis and volcanoes; climate- and weather-related disasters; as well as outbreaks of biological hazards, including crop pests and epidemics, Elsworth said.

Related: 10 signs that Earth's climate is off the rails

Over the past two decades, 350 to 500 medium- to large-scale disasters have occurred each year, the report's authors noted. They predicted that this number will reach 560 disasters a year (1.5 a day) by the year 2030. 

"The world needs to do more to incorporate disaster risk in how we live, build and invest, which is setting humanity on a spiral of self-destruction," Amina J. Mohammed, the UN's deputy secretary-general, said in a statement.

The authors highlight the COVID-19 pandemic as an example of myopic thinking and lack of understanding of disaster risks. "Myopic thinking meant that, despite warnings and data that a pandemic was overdue, preparedness was inadequate and governance systems across the world struggled to pivot to a new reality," they wrote. The severity of the pandemic was also exacerbated by populations across the globe being exposed to other health risks. "Exposure to underlying risk factors, such as high levels of air pollution, unsafe housing or limited access to health services, were found to significantly affect fatality rates," they wrote.

The authors also highlighted the growing risk of extreme weather events, which are becoming more common due to human-made climate change. Policymakers, they said, should work to climate-proof development and investments. For instance, Costa Rica implemented a carbon tax in 1997 to help reverse deforestation, which works to reduce disaster risks and benefit the economy, the UN report authors said in the statement. 

The authors found that not everyone is impacted by disasters equally. Eighteen out of the 20 countries with the highest disaster risk were middle- and lower-income countries with an average poverty rate of 34%. "By the end of this decade, climate change and disasters caused by natural hazards may push as many as 132 million people into poverty," Elsworth said.

But don't despair — the authors put together a three-action plan to help prevent this spiral of self-destruction. For one, humans need to stop undervaluing "climate change risk, costs to ecosystems and the positive social benefits of risk reduction," the authors wrote. The second action involves designing systems "to factor in how human minds make decisions about risk," they wrote. And lastly, governments and financial systems must work across disciplines to help people affected by disasters. Local leadership is a must during disasters, they wrote. "Rifts can emerge between the national and local levels during major crises, as was the case in many jurisdictions during the COVID-19 crisis. Autonomy for local-level action is essential."

The time for action, the authors say, is now.

Originally published in Live Science.

Giant "sinkholes" — one of which could devour an entire city block holding six-story buildings — are appearing along the Arctic seafloor, as submerged permafrost thaws and disturbs the area, scientists have discovered.

But even though human-caused climate change is increasing the average temperatures in the Arctic, the thawing permafrost that's creating these sinkholes seems to have a different culprit — heated, slowly moving groundwater systems. 

The Arctic permafrost at the bottom of the Canadian Beaufort Sea has been submerged for about 12,000 years, since the end of the last ice age, when meltwater from glaciers blanketed the region. Until now, the frozen seafloor had been hidden from scientists' peering eyes. This remote part of the Arctic has only recently become accessible to researchers on ships as climate change causes the sea ice to retreat, the researchers said. 

Mapping the seafloor

With access to the area, the study researchers relied on both ship-based sonar and an autonomous underwater vehicle (AUV) to complete high-resolution bathymetric surveys of the Canadian Beaufort Sea. 

"We know that big changes are happening across the Arctic landscape, but this is the first time we've been able to deploy technology to see that changes are happening offshore too," Charlie Paull, a geologist at Monterey Bay Aquarium Research Institute (MBARI), said in a statement. "While the underwater sinkholes we have discovered are the result of longer-term, glacial-interglacial climate cycles, we know the Arctic is warming faster than any region on Earth," added Paull, who co-led the research with Scott Dallimore from the Geological Survey of Canada and Natural Resources Canada, with an international team of researchers. 

Related: 'Last Ice Area' in the Arctic may not survive climate change

When the researchers first started undertaking seafloor surveys in the region in 2010, they focused on the shelf edge and slope in the Canadian Beaufort Sea. About 110 miles (180 kilometers) from the shore, they spotted a 59-mile-long (95 km) band of unusually rough terrain along the seafloor. That stretch of seafloor once marked the edge of the Pleistocene permafrost during the last ice age. The team wondered what was causing the rugged nature of the ocean bottom.

To understand how this roughness evolved over time and what might be causing it, the team conducted three more surveys, using AUVs in 2013 and 2017 and then ship sonar in 2019. These snapshots of the same areas over time showed the emergence of steep-sided and irregularly shaped depressions. The largest sinkhole-like crater is a whopping 738 feet (225 meters) long, 312 feet (95 m) wide and 92 feet (28 m) deep, the researchers said. 

Collapsing floor

Here's how the researchers propose the circular holes are forming: As gradual warming thaws the permafrost beneath the Arctic Shelf, an area that was once filled with a solid (frozen ground) becomes fluid. The surface material then collapses into that liquid-filled void; these seafloor collapses happen intermittently over time, the researchers said. 

Related: Why do ice ages happen?

In some areas, where the discharge of this warm groundwater is more limited, the seawater on the floor stays cold enough that any groundwater percolating up refreezes once it's reached near-surface sediments. That frozen sediment expands, heaving upward to form little conical mounds called pingos. These frozen mounds interrupted by the sinkholes are responsible for the unusual roughness that the researchers first spotted in their surveys.

The surveys also showed that the sinkholes are expanding over time. "The continued enlargement of some depressions observed over multiple surveys indicates that the development of these depressions is part of on-going processes," the researchers wrote in their research article published online March 14 in the journal Proceedings of the National Academy of Sciences.

As for the cause, the researchers said that slow changes in climate related to the ending of the last ice age — which have been occurring for thousands of years — are the likely culprits that started the cycle. Once the submerged permafrost begins to melt, the heated groundwater from that melted permafrost inches upward along the bottom of the still-frozen permafrost, leading to more thawing of those sediments above. The process continues in this way to give birth to lots of divots.

Originally published on Live Science.

The history of the universe and how it evolved is broadly accepted as the Big Bang model, which states that the universe began as an incredibly hot, dense point roughly 13.7 billion years ago. So, how did the universe go from being fractions of an inch (a few millimeters) across to what it is today?

Here is a breakdown of the Big Bang to now in 10 easy-to-understand steps.

Step 1: How it all started

The Big Bang was not an explosion in space, as the theory's name might suggest. Instead, it was the appearance of space everywhere in the universe, researchers have said. According to the Big Bang theory, the universe was born as a very hot, very dense, single point in space.

Cosmologists are unsure what happened before this moment, but with sophisticated space missions, ground-based telescopes and complicated calculations, scientists have been working to paint a clearer picture of the early universe and its formation.

A key part of this comes from observations of the cosmic microwave background, which contains the afterglow of light and radiation left over from the Big Bang. This relic of the Big Bang pervades the universe and is visible to microwave detectors, which allows scientists to piece together clues of the early universe.

In 2001, NASA launched the Wilkinson Microwave Anisotropy Probe (WMAP) mission to study the conditions as they existed in the early universe by measuring radiation from the cosmic microwave background. Among other discoveries, WMAP was able to determine the age of the universe — about 13.7 billion years old.

Step 2: The universe's first growth spurt

When the universe was very young — something like a hundredth of a billionth of a trillionth of a trillionth of a second (whew!) — it underwent an incredible growth spurt. During this burst of expansion, which is known as inflation, the universe grew exponentially and doubled in size at least 90 times.

"The universe was expanding, and as it expanded, it got cooler and less dense," David Spergel, a theoretical astrophysicist at Princeton University in Princeton, N.J., told SPACE.com. After inflation, the universe continued to grow, but at a slower rate. 

As space expanded, the universe cooled and matter formed.

Step 3: Too hot to shine

Light chemical elements were created within the first three minutes of the universe's formation. As the universe expanded, temperatures cooled and protons and neutrons collided to make deuterium, which is an isotope of hydrogen. Much of this deuterium combined to make helium.

For the first 380,000 years after the Big Bang, however, the intense heat from the universe's creation made it essentially too hot for light to shine. Atoms crashed together with enough force to break up into a dense, opaque plasma of protons, neutrons and electrons that scattered light like fog.

Step 4: Let there be light

About 380,000 years after the Big Bang, matter cooled enough for electrons to combine with nuclei to form neutral atoms. This phase is known as "recombination," and the absorption of free electrons caused the universe to become transparent. The light that was unleashed at this time is detectable today in the form of radiation from the cosmic microwave background.

Yet, the era of recombination was followed by a period of darkness before stars and other bright objects were formed.

Step 5: Emerging from the cosmic dark ages

Roughly 400 million years after the Big Bang, the universe began to come out of its dark ages. This period in the universe's evolution is called the age of re-ionization.

This dynamic phase was thought to have lasted more than a half-billion years, but based on new observations, scientists think re-ionization may have occurred more rapidly than previously thought.

During this time, clumps of gas collapsed enough to form the very first stars and galaxies. The emitted ultraviolet light from these energetic events cleared out and destroyed most of the surrounding neutral hydrogen gas. The process of re-ionization, plus the clearing of foggy hydrogen gas, caused the universe to become transparent to ultraviolet light for the first time.

Step 6: More stars and more galaxies

Astronomers comb the universe looking for the most far-flung and oldest galaxies to help them understand the properties of the early universe. Similarly, by studying the cosmic microwave background, astronomers can work backwards to piece together the events that came before.

Data from older missions like WMAP and the Cosmic Background Explorer (COBE), which launched in 1989, and missions still in operation, like the Hubble Space Telescope, which launched in 1990, all help scientists try to solve the most enduring mysteries and answer the most debated questions in cosmology.

Step 7: Birth of our solar system

Our solar system is estimated to have been born a little after 9 billion years after the Big Bang, making it about 4.6 billion years old. According to current estimates, the sun is one of more than 100 billion stars in our Milky Way galaxy alone, and orbits roughly 25,000 light-years from the galactic core.

Many scientists think the sun and the rest of our solar system was formed from a giant, rotating cloud of gas and dust known as the solar nebula. As gravity caused the nebula to collapse, it spun faster and flattened into a disk. During this phase, most of the material was pulled toward the center to form the sun.

Step 8: The invisible stuff in the universe

In the 1960s and 1970s, astronomers began thinking that there might be more mass in the universe than what is visible. Vera Rubin, an astronomer at the Carnegie Institution of Washington, observed the speeds of stars at various locations in galaxies.

Basic Newtonian physics implies that stars on the outskirts of a galaxy would orbit more slowly than stars at the center, but Rubin found no difference in the velocities of stars farther out. In fact, she found that all stars in a galaxy seem to circle the center at more or less the same speed.

This mysterious and invisible mass became known as dark matter. Dark matter is inferred because of the gravitational pull it exerts on regular matter. One hypothesis states the mysterious stuff could be formed by exotic particles that don't interact with light or regular matter, which is why it has been so difficult to detect. 

Step 9: The expanding and accelerating universe

In the 1920s, astronomer Edwin Hubble made a revolutionary discovery about the universe. Using a newly constructed telescope at the Mount Wilson Observatory in Los Angeles, Hubble observed that the universe is not static, but rather is expanding.

Decades later, in 1998, the prolific space telescope named after the famous astronomer, the Hubble Space Telescope, studied very distant supernovas and found that, a long time ago, the universe was expanding more slowly than it is today. This discovery was surprising because it was long thought that the gravity of matter in the universe would slow its expansion, or even cause it to contract.

Dark energy is thought to be the strange force that is pulling the cosmos apart at ever-increasing speeds, but it remains undetected and shrouded in mystery. The existence of this elusive energy, which is thought to make up 80% of the universe, is one of the most hotly debated topics in cosmology.

Step 10: We still need to know more

While much has been discovered about the creation and evolution of the universe, there are enduring questions that remain unanswered. Dark matter and dark energy remain two of the biggest mysteries, but cosmologists continue to probe the universe in hopes of better understanding how it all began.

The James Webb Space Telescope (JWST), launched in 2021, will continue the hunt for the elusive dark matter, as well as peering back to the beginning of time and the evolution of the universe using its infrared instruments.

Additional resources

For more information about the evolution of the universe check out, "The History of the Universe" by David H. Lyth or "A Brief History of Time" by Stephen Hawking. You can also keep up to date with the discoveries of JWST, visit NASA's dedicated webpage or the European Space Agency's dedicated webpage. 

Bibliography

Scientific American, "The Evolution of the Universe", October 1994. 

Walter Perry, "Origin and Evolution of the Universe", Journal of Modern Physics, Volume 12, November 2021.

Bharat Ratra and Michael S. Vogeley, "The Beginning and Evolution of the Universe", Publications of the Astronomical Society of the Pacific, Volume 120, March 2008, 

NASA, "Brief History of the Universe", December 2006. 

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Christopher Lyon, Postdoctoral researcher, Natural Resource Sciences, McGill University
Alex Dunhill, Research Fellow in Palaeobiology, University of Leeds
Andrew P. Beckerman, Professor in Evolutionary Ecology, University of Sheffield
Ariane Burke, Professor, Anthropology, Université de Montréal
Bethany Allen, PhD Student, School of Earth and Environment, University of Leeds
Chris Smith, NERC-IIASA Collaborative Research Fellow, University of Leeds
Daniel J. Hill, Lecturer, School of Earth and Environment, University of Leeds
Erin Saupe, Associate Professor, Palaeobiology, University of Oxford
James McKay, Manager, Centre for Doctoral Training, University of Leeds
Julien Riel-Salvatore, Professor, Anthropology, Université de Montréal
Lindsay C. Stringer, Professor, Environment and Geography, University of York
Rob Marchant, Professor of Tropical Ecology, University of York
Tracy Aze, Associate Professor, Earth and Environment, University of Leeds

There are many reports based on scientific research that talk about the long-term impacts of climate change — such as rising levels of greenhouse gases, temperatures and sea levels — by the year 2100. The Paris Agreement, for example, requires us to limit warming to under 2.0 degrees Celsius above pre-industrial levels by the end of the century.

Every few years since 1990, we have evaluated our progress through the Intergovernmental Panel on Climate Change's (IPCC) scientific assessment reports and related special reports. IPCC reports assess existing research to show us where we are and what we need to do before 2100 to meet our goals, and what could happen if we don't.

The recently published United Nations assessment of Nationally Determined Contributions (NDCs) warns that current promises from governments set us up for a very dangerous 2.7 degrees Celsius warming by 2100: this means unprecedented fires, storms, droughts, floods and heat, and profound land and aquatic ecosystem change.

While some climate projections do look past 2100, these longer-term projections aren't being factored into mainstream climate adaptation and environmental decision-making today. This is surprising because people born now will only be in their 70s by 2100. What will the world look like for their children and grandchildren?

To grasp, plan for and communicate the full spatial and temporal scope of climate impacts under any scenario, even those meeting the Paris Agreement, researchers and policymakers must look well beyond the 2100 horizon.

After 2100

In 2100, will the climate stop warming? If not, what does this mean for humans now and in the future? In our recent open-access article in Global Change Biology, we begin to answer these questions.

We ran global climate model projections based on Representative Concentration Pathways (RCP), which are "time-dependent projections of atmospheric greenhouse gas (GHG) concentrations." Our projections modeled low (RCP6.0), medium (RCP4.5) and high mitigation scenarios (RCP2.6, which corresponds to the "well-below 2 degrees Celsius" Paris Agreement goal) up to the year 2500.

We also modelled vegetation distribution, heat stress and growing conditions for our current major crop plants, to get a sense of the kind of environmental challenges today's children and their descendants might have to adapt to from the 22nd century onward.

In our model, we found that global average temperatures keep increasing beyond 2100 under RCP4.5 and 6.0. Under those scenarios, vegetation and the best crop-growing areas move towards the poles, and the area suitable for some crops is reduced. Places with long histories of cultural and ecosystem richness, like the Amazon Basin, may become barren.

Further, we found heat stress may reach fatal levels for humans in tropical regions which are currently highly populated. Such areas might become uninhabitable. Even under high-mitigation scenarios, we found that sea level keeps rising due to expanding and mixing water in warming oceans.

Although our findings are based on one climate model, they fall within the range of projections from others, and help to reveal the potential magnitude of climate upheaval on longer time scales.

To really portray what a low-mitigation/high-heat world could look like compared to what we've experienced until now, we used our projections and diverse research expertise to inform a series of nine paintings covering a thousand years (1500, 2020, and 2500 CE) in three major regional landscapes (the Amazon, the Midwest United States and the Indian subcontinent). The images for the year 2500 center on the RCP6.0 projections, and include slightly advanced but recognizable versions of today’s technologies.

An alien future?

Between 1500 and today, we have witnessed colonization and the Industrial Revolution, the birth of modern states, identities and institutions, the mass combustion of fossil fuels and the associated rise in global temperatures. If we fail to halt climate warming, the next 500 years and beyond will change the Earth in ways that challenge our ability to maintain many essentials for survival — particularly in the historically and geographically rooted cultures that give us meaning and identity.

The Earth of our high-end projections is alien to humans. The choice we face is to urgently reduce emissions, while continuing to adapt to the warming we cannot escape as a result of emissions up to now, or begin to consider life on an Earth very different to this one.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher.

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Karen D. Holl, Professor of Restoration Ecology, University of California, Santa Cruz

If we planted 8 billion trees a year for 20 years, what would happen on Earth? – Shivam K., age 14, Nawada, Bihar, India

Politicians, business leaders, YouTubers and celebrities are calling for the planting of millions, billions or even trillions of trees to slow climate change.

There are currently almost 8 billion people on Earth. If every single person planted a tree each year for the next 20 years, that would mean roughly 160 billion new trees.

Could massive tree planting actually slow climate change?

Trees and carbon

Carbon dioxide is the main gas that causes global warming. Through photosynthesis, trees and other plants transform carbon dioxide from the atmosphere into carbohydrates, which they use to make stems, leaves and roots.

The amount of carbon a tree can store varies a great deal. It depends on the tree species, where it is growing and how old it is.

Let’s say the average tree takes up 50 pounds of carbon dioxide a year. If a person planted a tree every year for 20 years – and each one survived, which is highly unlikely – those 20 trees would take up about 1,000 pounds, or half a ton, of carbon dioxide per year.

The average person in the United States produces a whopping 15.5 tons of carbon dioxide a year compared with 1.9 tons for an average person in India. This means that if each person in the U.S. planted one tree per year it would offset only about 3% of the carbon dioxide they produce each year, after all 20 trees had matured. But, it would offset 26% for somebody in India.

Planting trees is certainly part of the solution to climate change, but there are more important ones.

Protecting the trees we have

There are about 3 trillion trees on Earth, which is only half as many as 12,000 years ago, at the start of human civilization.

People cut down an estimated 15 billion trees each year. A lot of those trees are in tropical forests, but deforestation is happening all over the planet.

Protecting existing forests makes sense. Not only do they absorb carbon dioxide in the trees and the soil, but they provide habitat for animals. Trees can provide firewood and fruit for people. In cities, they can offer shade and recreational spaces.

But trees should not be planted where they didn’t grow before, such as in native grasslands or savannas. These ecosystems provide important habitat for their own animals and plants – and already store carbon if they are left undisturbed.

Doing more

To slow climate change, people need to do much more than plant trees. Humans need to reduce their carbon dioxide and other greenhouse gas emissions quickly by transitioning to renewable energy sources, like solar and wind. People should also reduce the amount they drive and fly – and eat less meat, as meat has a much larger carbon footprint per calorie than grains and vegetables.

It is important that everybody – businesses, politicians, governments, adults and even kids – do what they can to reduce fossil fuel emissions. I know it can seem pretty overwhelming to think about what you as one person can do to help the planet. Fortunately, there are many options.

Volunteer with a local conservation organization, where you can help protect and restore local habitats. Discuss with your family new lifestyle choices, like biking, walking or taking public transit rather than driving.

And don’t be afraid to lead an effort to protect trees, locally or globally. Two 11-year-old Girl Scouts, concerned about the destruction of rainforests for palm oil plantations, led an effort to eliminate palm oil in Girl Scout cookies.

Sometimes change is slow, but together people can make it happen.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher.

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Navid Constantinou, Research Fellow, Australian National University

Adele Morrison, Research Fellow, Australian National University

Andrew Kiss, Research fellow, Australian National University

Andy Hogg, Professor, Australian National University

Josué Martínez Moreno, P.h.D. candidate, Australian National University

Matthew England, Australian Research Council Laureate Fellow; Deputy Director of the Climate Change Research Centre (CCRC); Chief Investigator in the ARC Centre of Excellence in Climate System Science, UNSW

Scientists already know the oceans are rapidly warming and sea levels are rising. But that's not all. Now, thanks to satellite observations, we have three decades' worth of data on how the speeds of ocean surface currents are also changing over time.

In research published in April in the journal Nature Climate Change we detail our findings on how ocean currents have become more energetic over large parts of the ocean.

What are ocean eddies?

If you looked down at the ocean from a bird's eye view, you would see some mesmerizing circular motions in the water. These features are called "ocean eddies." They give the ocean an artistic flavor, reminiscent of Van Gogh's Starry Night.

Eddies span somewhere between 10 and 100 kilometers across. They’re found all over the oceans. Certain regions, however, are particularly rich in eddies.

These include the Gulf Stream in the North Atlantic, the Kuroshio Current in the North Pacific, the Southern Ocean which surrounds Antarctica and, closer to Australia, the East Australian Current — made famous by the film "Finding Nemo."

Ocean eddies are an integral part of ocean circulation. They move warm and cold waters from one location to others. They mix heat, carbon, salt and nutrients, and affect ocean conditions both regionally and globally.

Read more: An ocean like no other: the Southern Ocean's ecological richness and significance for global climate

Satellites constantly watch the ocean

One way we monitor movement on the ocean's surface is by using specialized, powerful satellites orbiting Earth. Although these satellites are thousands of kilometers above us, they can detect even just a few centimeters of change in the sea's surface elevation.

Then, through data analysis, we can take the change in sea surface elevation and translate it into ocean flow speeds. This can then tell us how "energetic" an ocean eddy is.

By carefully analyzing satellite observations, our team discovered clear changes in the distribution and strength of ocean eddies. And these changes have never been detected before.

How eddies have been changing

Using available data from 1993 until 2020, we analyzed changes in the strength of eddies across the globe. We found regions already rich in eddies are getting even richer! And on average, eddies are becoming up to 5% more energetic each decade.

One of the regions we found with the biggest change is the Southern Ocean, where a massive 5% increase per decade was detected in eddy activity. The Southern Ocean is known to be a hotspot for ocean heat uptake and carbon storage.

Until recently, scientists could only observe changes in ocean eddies by using either sparse ocean measurements or the limited satellite record. The satellite record has only just become long enough for experts to draw robust conclusions about the likely longer-term trends of eddy behavior.

Why is this important?

Ocean eddies play a profound role in the climate by regulating the mixing and transport of heat, carbon, biota and nutrients in the oceans. Thus, our research may have far-reaching implications for future climate.

Scientists have known for decades that eddies in the Southern Ocean affect the overturning circulation of the ocean. As such, changes of the magnitude observed for eddies could impact the rate at which the ocean draws down heat and carbon.

But eddies are often not taken into account in climate predictions of a warming world. Since they are relatively small, they remain practically "invisible" in current models used to project future climate.

The impact of eddies is therefore either not resolved in climate projections, or is severely underestimated. This is particularly concerning in light of our discovery eddies are becoming more energetic.

Our research emphasizes how crucial it is to incorporate ocean eddies into future climate projections. If we don’t, we could be overlooking a critical detail.

Read more: How an alien seaweed invasion spawned an Antarctic mystery

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher. 

The 2021 Atlantic hurricane season has officially begun, and it's expected to bring a higher-than-average number of storms in the months ahead.

There is a 60% chance that the Atlantic hurricane season, which runs from Tuesday (June 1) to Nov. 30, will be an "above-normal" season, the National Oceanic and Atmospheric Administration (NOAA) said in a statement on May 20. 

The season will likely bring 13 to 20 named storms, or storms with winds of 39 mph (63 km/h) or higher, according to NOAA. Of those storms, six to 10 could become hurricanes with winds of 74 mph (119 km/h) or higher, with three to five becoming "major" hurricanes with winds of 111 mph (179 km/h) or higher. 

An average hurricane season brings about 14 named storms, including three major hurricanes and four weaker hurricanes, according to the statement.

Related: Hurricane season: How long it lasts and what to expect

This year's hurricane season follows on the heels of an extremely active 2020 hurricane season that broke records with 30 named storms; by September, the National Hurricane Center (NHC) ran out of pre-set names for the storms and started naming them after Greek letters, Live Science previously reported. Last year wasn't the first time that has happened: in 2005, the NHC also had to use Greek letters when an extremely active hurricane season brought 28 named storms.

"Although NOAA scientists don't expect this season to be as busy as last year, it only takes one storm to devastate a community," Ben Friedman, acting NOAA administrator, said in the statement. "The forecasters at the National Hurricane Center are well-prepared with significant upgrades to our computer models, emerging observation techniques and the expertise to deliver the life-saving forecasts that we all depend on during this, and every, hurricane season."

This year's first Atlantic storm will be named "Ana," the second "Bill," followed by "Claudette, Danny, Elsa, Fred, Grace" and so on; the last storm on the list is "Wanda," according to the National Hurricane Center and the Central Pacific Hurricane Center.

Since the 1980s, the intensity, frequency and duration of North Atlantic hurricanes have increased; and as climate change continues to warm the planet, storm intensity and rainfall rates are expected to continue to increase, according to NASA. 

This year's increased activity is a combination of an "ongoing high-activity era," warmer-than-average sea-surface temperatures, weaker wind shear in the tropical Atlantic Ocean (which when strong can zap energy from storms), more west African monsoon activity and a neutral climate pattern called El Niño Southern Oscillation that won't suppress hurricane activity, according to NOAA.

Though the Atlantic will likely be hit with a higher-than-average number of storms, the Central Pacific will likely have an average or below-average number of storms, with only about two to five tropical cyclones expected to form; the average for the region is four to five  tropical cyclones, according to NOAA. The Central Pacific hurricane season also runs from June 1 to Nov. 30.

To prepare for the hurricane season, people should visit the Federal Emergency Management Agency's (FEMA's) Ready.gov website and also visit the NHC's hurricanes.gov to stay up-to-date on hurricane warnings throughout the season, according to the statement.

Originally published on Live Science.

The 2021 Atlantic hurricane season has officially begun, and it's expected to bring a higher-than-average number of storms in the months ahead.

There is a 60% chance that the Atlantic hurricane season, which runs from Tuesday (June 1) to Nov. 30, will be an "above-normal" season, the National Oceanic and Atmospheric Administration (NOAA) said in a statement on May 20. 

The season will likely bring 13 to 20 named storms, or storms with winds of 39 mph (63 km/h) or higher, according to NOAA. Of those storms, six to 10 could become hurricanes with winds of 74 mph (119 km/h) or higher, with three to five becoming "major" hurricanes with winds of 111 mph (179 km/h) or higher. 

An average hurricane season brings about 14 named storms, including three major hurricanes and four weaker hurricanes, according to the statement.

Related: Hurricane season: How long it lasts and what to expect

This year's hurricane season follows on the heels of an extremely active 2020 hurricane season that broke records with 30 named storms; by September, the National Hurricane Center (NHC) ran out of pre-set names for the storms and started naming them after Greek letters, Live Science previously reported. Last year wasn't the first time that has happened: in 2005, the NHC also had to use Greek letters when an extremely active hurricane season brought 28 named storms.

"Although NOAA scientists don't expect this season to be as busy as last year, it only takes one storm to devastate a community," Ben Friedman, acting NOAA administrator, said in the statement. "The forecasters at the National Hurricane Center are well-prepared with significant upgrades to our computer models, emerging observation techniques and the expertise to deliver the life-saving forecasts that we all depend on during this, and every, hurricane season."

This year's first Atlantic storm will be named "Ana," the second "Bill," followed by "Claudette, Danny, Elsa, Fred, Grace" and so on; the last storm on the list is "Wanda," according to the National Hurricane Center and the Central Pacific Hurricane Center.

Since the 1980s, the intensity, frequency and duration of North Atlantic hurricanes have increased; and as climate change continues to warm the planet, storm intensity and rainfall rates are expected to continue to increase, according to NASA. 

This year's increased activity is a combination of an "ongoing high-activity era," warmer-than-average sea-surface temperatures, weaker wind shear in the tropical Atlantic Ocean (which when strong can zap energy from storms), more west African monsoon activity and a neutral climate pattern called El Niño Southern Oscillation that won't suppress hurricane activity, according to NOAA.

Though the Atlantic will likely be hit with a higher-than-average number of storms, the Central Pacific will likely have an average or below-average number of storms, with only about two to five tropical cyclones expected to form; the average for the region is four to five  tropical cyclones, according to NOAA. The Central Pacific hurricane season also runs from June 1 to Nov. 30.

To prepare for the hurricane season, people should visit the Federal Emergency Management Agency's (FEMA's) Ready.gov website and also visit the NHC's hurricanes.gov to stay up-to-date on hurricane warnings throughout the season, according to the statement.

Originally published on Live Science.

The idea of threats to Earth from outer space sounds like science fiction, but at some level our planet has always been vulnerable to them — think of the giant asteroid that wiped out the dinosaurs 65 million years ago. 

Fortunately, such occurrences are extremely rare; but other natural phenomena, such as solar storms, can strike from space much more frequently. These have little direct effect on living things, but they can wreak havoc on electronic systems we increasingly depend on, particularly satellite-based technologies. 

To make matters worse, the proliferation of human-made satellites has created a space hazard of its own, as the loads of orbiting debris have the potential to destroy other satellites.

Related: Debris from SpaceX rocket launch falls on farm in central Washington

In the U.S., tackling these threats is the responsibility of several organizations: Both NASA and the U.S. Space Force tracks space debris; the National Oceanic and Atmospheric Administration monitor “space weather";  and NASA’s Planetary Defense Coordination Office coordinates the search for potentially hazardous asteroids and other near-Earth objects (NEOs). 

In contrast, the European Space Agency (ESA) has pulled all these activities together under the umbrella of its Space Situational Awareness program. Set up in 2009, this program is divided into three segments covering space debris, space weather and NEOs.

The problem with space debris 

The satellites humans depend on for communication, navigation and environmental monitoring are under increasing threat from all the junk that’s in orbit with them. This junk includes derelict satellites and the rocket stages used to launch them, but if that was the extent of the problem there would be a manageable number of objects to keep track of. Unfortunately, those objects have a tendency to multiply, partly due to explosions caused by residual fuel and partly through collisions. The result? Thousands of smaller fragments pose at least as much risk as the original object, due to their high speed and the fact that they are all moving on slightly different orbits. (This is due to the additional random velocities imparted by the explosion.)

Working satellites are equipped with maneuvering thrusters, so they can be moved to a different orbit if a piece of space debris is known to be heading their way. But with tens of thousands of objects large enough to cause serious problems in orbit — ranging in size from 0.4 inches (one centimeter) to 80 feet (25 meters) or more — it’s no easy task to keep track of them all. 

Yet that’s exactly what the Space Surveillance and Tracking segment of ESA’s Space Situational Awareness program has to do. It employs a network of telescopes, radars and laser-ranging stations to detect and track objects, and then processes the resulting data at ESA mission control in Darmstadt, Germany. Mission control will then issue an alert if evasive action is deemed necessary.

This system works well at the moment, but that won’t always be the case, the BBC reported. The number of new satellites being launched is higher than it has ever been, according to the BBC, while the number of fragmentary objects is increasing due to ongoing collisions. The worry is that the amount of space debris could reach a tipping point beyond which there is a continuous cascade of self-generating collisions. Known as the Kessler syndrome, this would render certain orbits unusable if it continued unchecked. 

For this reason, the ESA is considering methods for the active removal of space debris. Its ClearSpace-1 mission, planned to launch in 2025, will be the first in the world to remove a piece of space debris from orbit, if all goes according to plan.

ClearSpace-1 will target a specific piece of space junk — a 220-lb. (100 kilograms) payload adapter called Vespa that the ESA used in 2013 to deploy a satellite. After rendezvousing with Vespa, ClearSpace-1 will grab hold of it with robotic arms, then fire its rocket to break out of orbit. The plan is that both ClearSpace-1 and Vespa will burn up on re-entry into Earth’s atmosphere.

Although there are thousands of pieces of space junk, the most serious threat comes from the largest objects. At the International Astronautical Congress in October 2020, Darren McKnight of the Centauri corporation presented a list of the 50 “statistically most concerning” debris objects, which was also reported in the journal Acta Astronautica. These were ranked not just by size, but also by the persistence of their orbits and their likelihood of colliding with another object. More than 75% of the top 50 are spent launch stages that remain in orbit, while 80% originated in the last century, before space agencies started taking specific measures to limit orbital debris. The ESA has the dubious honor of having the top-ranked satellite on the list — the now-defunct environmental monitoring satellite Envisat, launched in 2002.

Related: Defunct US weather satellite breaks up in Earth orbit

When space weather turns deadly

As far as Earth is concerned, the main source of space weather is the sun, according to the ESA. Space weather events such as solar flares and coronal mass ejections (CMEs) have been occurring since time immemorial, but it’s only in the modern world that they’ve become a significant hazard. As long as people stayed at ground level and didn’t rely on electronic systems for navigation and communication, or on the electrical grid for power, they could remain blissfully unaware of solar activity. But in today’s world that’s no longer an option.

Adverse effects of space weather are particularly apparent in the space environment itself, where high-energy radiation can degrade a satellite’s solar panels and damage electronic systems, especially during severe solar storms. This has consequences for satellite TV and broadband services, as well as for ships and aircraft that rely on satellites for navigation. 

But high-energy solar radiation can also pose a hazard to people on Earth, such as airline crew members, whose health may be endangered if they spend a lot of time at high altitude, while severe solar storms can disrupt radio communications and the electrical power grid.

This means that someone has to keep an eye on the ever-changing vagaries of space weather, just as meteorologists do with ordinary weather. Space weather forecasters work in a similar way to their terrestrial counterparts, combining data from a variety of sources — both on the ground and in space — with computer models to work out what is likely to happen. However, unlike terrestrial forecasts aimed at the general public, space weather forecasts are targeted at the business sectors that are most likely to be affected. ESA’s Space Weather Network, for example, provides tailored services to a variety of industries, ranging from airlines and power distribution systems to spacecraft operators and auroral tourist agencies.

As with the ClearSpace-1 mission in the space debris domain, ESA’s space weather segment is planning a world first. Although numerous satellites operated by ESA, NASA and other agencies help to monitor space weather, these satellites all perform other tasks as well. In contrast, ESA’s Lagrange spacecraft will be the first to focus solely on space weather. To this end, it will be positioned “side-on” to the Earth-sun axis, at equal distances from both, to give it the best possible view of solar storms heading toward our planet.

Dodging nearby asteroids

Their name is slightly misleading because NEOs aren’t always near Earth — they may be hundreds of millions of miles away on the other side of the sun, according to Space.com. But they’re moving along orbits that cross Earth’s orbit, or come close to it, which raises the risk of a future collision. This doesn’t necessarily spell disaster, because many NEOs are so small they will burn up as they enter the atmosphere. Telescopes can typically detect those asteroids or comets that are large enough to inflict serious damage when they’re still a long way from impact. This is where the NEO segment of ESA’s Space Situational Awareness program comes in.

The NEO segment is made up of a number of components, including a Europe-wide network of observers — both professionals and volunteers — to determine the current position of NEOs. These observations then feed into a central analysis team that predicts future orbits, assesses the collision risk, and, if necessary, issues warnings to civil authorities if the predicted impact point lies inside Europe. On a more upbeat note, ESA is also investigating ways to deflect an incoming NEO before it hits Earth.

Additional resources: 

• Read more about the ESA's Space Situational Awareness program
• Discover everything you need to know about space weather
• How space agencies scan the skies for asteroid threats 

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

James W. Hurrell, Professor and Scott Presidential Chair in Environmental Science and Engineering, Colorado State University

Ambuj D Sagar, Founding Head, School of Public Policy, and Vipula and Mahesh Chaturevdi Professor of Policy Studies, The Indian Institute of Technology Delhi

Marion Hourdequin, Professor of Philosophy, Colorado College

A new report from the National Academies of Sciences, Engineering and Medicine tackles a controversial question: Is solar geoengineering – an approach designed to cool the Earth by reflecting sunlight back into space or modifying clouds – a potential tool for countering climate change?

The report, produced by a committee of 16 experts from diverse fields, does not take a position but concludes that the concept should be studied. It calls for creating a multidisciplinary research program, in coordination with other countries and managed by the U.S. Global Change Research Program, that seeks to fill in the many knowledge gaps on this issue.

The study emphasizes that such research is not a substitute for cutting greenhouse gas emissions and should be a minor part of the U.S. response to climate change. It notes that “engineering the climate” would not address the root cause of climate change – greenhouse gas emissions from human activities. And it calls for a research program that draws on physical science, social science and ethics and includes public input.

These perspectives from three members of the study committee underline the complexity of this issue.

Three options, many questions

James W. Hurrell, Professor and Scott Presidential Chair of Environmental Science and Engineering, Colorado State University

Solar geoengineering strategies are very controversial within and beyond the climate science community. It is a major step forward to have 16 experts from different disciplines agree that now is the time to establish a research program on this topic. Our committee traveled a long road to reach this recommendation, working through many complex and contentious issues to reach consensus, but we did it collegially and productively. Each of us learned a great deal.

The three options we considered raise many questions:

– Stratospheric aerosol injection would increase the number of small reflective particles (aerosols) in the upper atmosphere to increase reflection of sunlight back into space. While strong evidence exists that this approach can induce cooling at a global scale, there is limited understanding of how cooling potential relates to the amounts of injected aerosols, their location and type, and the ensuing regional climate responses and impacts.

– Marine cloud brightening would add materials to low clouds over the ocean to make them more reflective. Water vapor in clouds condenses into droplets when it comes into contact with particles, such as salt; adding particles produces more droplets, making the clouds more reflective.

Where and by how much the brightness of clouds can be modified, and whether feedback processes will mask or amplify some of the effects, are important research questions. Key processes occur at scales too small to include directly into the current generation of global climate models, and these process uncertainties will need to be reduced in order to develop reliable projections of climate impacts.

– Cirrus cloud thinning would seek to reduce the formation of wispy, thin clouds that retain heat radiating upward from Earth’s surface. The efficacy of this approach is unknown because of very limited understanding of cirrus cloud properties and the microphysical processes determining how cirrus clouds may be altered. Existing climate model simulations have yielded contradictory results.

Given the risks of rapid warming and its impacts, it is important to consider a portfolio of response options, and to understand as quickly and efficiently as possible whether solar geoengineering could be a reasonably safe and effective option. A transdisciplinary, coordinated and well-governed research program might prove that more investment is warranted. Or it could indicate that solar geoengineering should not be considered further. The key point is that either outcome will be guided by sound science.

A thoughtful and inclusive process

Ambuj D. Sagar, Founding Head, School of Public Policy, and Professor of Policy Studies, The Indian Institute of Technology Delhi

Few climate issues are as polarizing as solar geoengineering, and for good reason. To many, even considering it could dilute efforts to cut emissions. It also reinforces the notion that as a society we are willing to place our faith in technology to solve our self-inflicted problems.

But refusing to engage with solar geoengineering also raises questions. Can we be sure that we won’t need it in the future? What if greenhouse warming generates horrendous climate impacts? And if it turns out that solar geoengineering is not technically feasible or socially acceptable, should we not learn that now?

This report recognizes that there is value in understanding more about the feasibility, acceptance, risks, ethics and governance of solar geoengineering to inform decision-making. But it also calls for a measured, nuanced and integrative approach. And it makes the point that exploring solar geoengineering should not compromise research or action on climate mitigation and adaptation.

Public engagement and participation, and insights from various disciplines, are key to carrying out effective research on solar geoengineering. At the same time, suitable expertise and institutional arrangements are needed to engage better with this complex topic. We need to understand how to effectively enhance such participation and strengthen such capacity.

Paying attention to these issues will open the door to including perspectives and researchers from the global south and other communities that often are marginalized. It also will help make the research agenda more robust and help people better understand potential risks around the world from solar geoengineering. A strong and inclusive research program should also fully involve developing countries and other relevant communities in exploring governance models for solar geoengineering.

Our panel recommended that the proposed U.S. research program be carried out in coordination with other countries. We hope this approach will spur deeper engagement worldwide, especially by developing countries that need to be part of global conversations and decisions on this issue.

Overall, I hope that perspectives and approaches presented in this report will catalyze a thoughtful and socially robust research program and equally thoughtful deliberations by scholars, policymakers and citizens on this thorny topic.

Broadening the discussion

Marion Hourdequin, Professor of Philosophy, Colorado College

Geoengineering evolved from a fringe concept to a serious research topic less than 20 years ago, and today solar geoengineering technologies are largely in the idea stage. Computer modeling simulations and natural analogs such as volcanoes indicate that adding reflective aerosols to the stratosphere or increasing the “brightness” of marine clouds could have cooling effects. However, there are risks and uncertainties associated with these approaches, and the potential benefits – which may not be evenly distributed around the globe – are not well understood.

For example, scientists know very little about the regional effects of different solar geoengineering strategies. And researchers are just starting to explore the ecological, social, political, economic and ethical dimensions of these approaches.
What’s more, many people in the U.S. and the world are unaware that research is moving forward and outdoor experiments have been proposed. So far, discussions about solar geoengineering have been concentrated among a relatively small group of researchers, primarily from North America and Europe.

[Over 100,000 readers rely on The Conversation’s newsletter to understand the world. Sign up today.]

But like climate change itself, solar geoengineering would affect everyone. The technologies that our committee considered would have global and multigenerational effects. With this in mind, now is the time for broader and more inclusive conversations about how solar geoengineering should be studied and governed – and whether or not it should be seriously considered. These conversations need to include climate-vulnerable communities, Indigenous peoples and nations of the global south.

Our committee’s report calls for a program that weaves together multidisciplinary research, public and stakeholder engagement, and thoughtful limits and guidelines for research. This program should facilitate cooperation and capacity building, support a more demographically and geographically diverse research community, enable equitable participation and prioritize strategies that build trust, transparency and legitimacy.

Geoengineering raises big technical, social and ethical questions that should be informed by research but can’t be adequately answered by a small set of experts. And regardless of what we learn through geoengineering research, one thing is clear: Reducing emissions, decarbonizing economies and supporting adaptation to current and future climate impacts need to take center stage.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher. 

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Nicolás Younes Cárdenas, Postdoctoral research fellow, James Cook University

Karen Joyce, Senior Lecturer - Remote sensing and spatial information, James Cook University

Stefan W Maier, Adjunct Research Fellow, James Cook University

Australia is home to around 2% of the world’s mangrove forests and is the fifth most mangrove-forested country on Earth. Mangroves play a crucial role in the ecosystem thanks to the dizzying array of plants, animals and birds they feed, house and protect.

Mangrove forests help protect coastal communities from cyclones and storms by absorbing the brunt of a storm’s energy. They help our fight against climate change by storing vast amounts of carbon that would otherwise be released as greenhouse gases.

In other words, mangroves are some of our most precious ecosystems. Despite their importance, there is much we don’t know about these complex wetland forests. For example, when does their growing season start? And, how long does it last?

Usually, answering these types of questions requires frequent data collection in the field, but that can be costly and time-consuming. An alternative is to use satellite images. In the future, this will allow us to track the impacts of climate change on mangroves and other forests.

What is phenology?

Our research used satellite images to study the life cycles of mangrove forests in the Northern Territory, Queensland, and New South Wales. We compared the satellite images with field data collected in the 1980s, 1990s and 2000s, and found a surprising degree of variation in mangrove life cycles.

We're using the phrase life cycle, but the scientific term is "phenology." Phenology is the study of periodic events in the life cycles of plants and animals. For example, some plants flower and fruit during the spring and summer, and some lose their leaves in autumn and winter.

Phenology is important because when plants are growing, they absorb carbon from the atmosphere and store it in their leaves, trunks, roots, and in the soil. As phenology is often affected by environmental conditions, studying phenology helps us understand how climate change is affecting Australian ecosystems such as mangrove forests.

So how can we learn a lot in a short amount of time about mangrove phenology? That's where satellite imagery comes in.

How we use satellites to study mangrove phenology

Satellites are an excellent tool to study changes in forest health, area, and phenology. Some satellites have been taking images of Earth for decades, giving us the chance to look back at the state of mangrove forests from 30 years ago or more.

You can think of satellite images much like the photo gallery in your smartphone: you can see many of your family members in a single image, and you can see how everyone grows and "blooms" over time. In the case of mangroves, we can see different regions and species in a single satellite image, and we can use past images to study the life cycles of mangrove forests.

For example, satellite images depicted below, which use data from the Australian government's National Maps website, show how mangroves forests have changed in the Kimberley region of Western Australia between 1990 and 2019. You can see how the mangrove forest has reduced in some areas, but expanded in others. Overall, this mangrove forest seems to be doing pretty well thanks in large part to the fact this area has a reasonably small human population.

Our study of satellite images of mangrove forests in the Northern Territory, Queensland, and New South Wales — and how they compared with data collected on the ground — found not all mangroves have the same life cycles.

For instance, many mangrove species grow new leaves only once per year, while other species grow new leaves twice a year. These subtle, but important differences will allow us to track the impacts of climate change on mangroves and other forests.

How climate change affects mangrove phenology

Climate change is changing the phenology of many forests, causing them to flower and fruit earlier than expected.

Science cannot yet tell us exactly how mangrove phenology will be affected by climate change but the results could be catastrophic. If mangroves flower or fruit earlier than expected, pollinators such as bats, bees and birds may starve or move to a different forests. Without pollinators, mangroves may not reproduce and can die.

The next step in our research is to figure out how climate change is affecting the life cycles of mangroves. To do this, we will use satellite images of mangroves across Australia and factor in data on temperature and rainfall.

We think rising temperatures are causing longer periods of leaf growth, a theory we plan to test by studying data from now with satellite images from the '80s and '90s.

Satellite monitoring can't do it all

Satellites can tell us a lot about how a mangrove forest is faring. For example, satellite images captured a dieback event (depicted below, using data from the Australian government's National Maps website) that happened between 2015 and 2016, when around 7,400 hectares of mangroves died in the Gulf of Carpentaria due to drought and unusually high air and sea temperatures.

But satellite monitoring is not enough on its own and cannot capture the detail you can get on the ground. For example, satellites cannot capture the flowering or fruiting of mangroves because flowers are often too small and fruits are often camouflaged. Also, satellites cannot capture what happens under the canopy.

It is also important to recognise the work of researchers on the ground. Ground data allows us to validate or confirm the information we see in satellite images. When we noted some mangrove forests were growing leaves twice per year, we validated this observation with field data, and confirmed with experts in mangrove ecosystems. Field data is crucial to understand the life cycles of ecosystems worldwide and how forests are responding to changes in the climate.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher. 

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Laurette Piani, Cosmochimiste, chargée de recherche CNRS au Centre de Recherches Pétrographiques et Géochimiques (CRPG) de Nancy, CNRS, Université de Lorraine

Guillaume Paris, Géochimiste, chargé de recherche CNRS au Centre de recherches pétrographiques et géochimiques de Nancy, Université de Lorraine

Water is essential to life as we know it and it seems completely normal to have water all around us. Yet Earth is the only known planet to be covered by oceans. Do we know exactly where its water came from?

This is not a simple question: it was long thought that Earth formed dry — without water, because of its proximity to the Sun and the high temperatures when the solar system formed. In this model, water could have been brought to Earth by comets or asteroids colliding with the Earth. Such a complex origin for water would likely mean that our planet is unique in the universe.

However, in a 2020 study, we showed that water — or at least its components, hydrogen and oxygen — may have been present in the rocks that initially formed the Earth. If that is so indeed, other "blue planets" with liquid water are more likely to exist elsewhere.

Water on Earth, water inside the Earth

Liquid water covers more than 70% of Earth's surface, with about about 95.6% of it in oceans and seas, and the remaining 4% in glaciers, ice caps, groundwater, lakes, rivers, soil humidity, and the atmosphere.

But most of Earth's water is deep underground: between one and ten times the volume of the oceans are contained in the mantle.

At the surface of the Earth, "water" means two hydrogens for each oxygen (H20), whereas what we call "water" in the mantle corresponds to hydrogen incorporated in minerals, magmas and fluids. This hydrogen can bond with surrounding oxygen to form water at the appropriate temperature and pressure conditions.

While water represents less than 0.5% of the mass of the Earth, it is key to the evolution of the planet itself and to life at its surface.

In the early solar system, there was a lot of hydrogen, mainly in the form of dihydrogen gas (H2), or bonded with oxygen atoms to form water (H2O). However, Earth and the other rocky planets (Mercury, Venus, and Mars) formed near the sun, where it was too hot for water to incorporate into rock as ice: it just would have evaporated. So why does the Earth now have so much water, both in its mantle and on its surface?

The prevalent hypothesis: hydrogen delivered to Earth by hydrated asteroids

Some meteorites, called chondrites, come from small asteroids that, unlike the planets, have not geologically evolved since their formation. They are good witnesses of the first millions of years of the solar system.

The carbonaceous chondrites for instance formed far enough away from the Sun to initially contain water ice (all of which has since been incorporated in hydrated minerals through hydrothermal alteration). Contrastingly, ordinary and enstatite chondrites formed closer to the sun where water was gaseous and was incorporated in large amounts into rocks: like the rocky planets, ordinary and enstatite chondrites are considered to be "dry."

Until now, the accepted hypothesis was that Earth formed from dry materials, and that its water was delivered by celestial bodies that formed further from the sun: hydrated meteorites, such as carbonaceous chondrites, or comets — although this last hypothesis was recently thwarted by the ESA space probe Rosetta.

Another origin for Earth’s water?

Our study tells a different story. We analyzed the hydrogen in enstatite chondrites. Remember that these are among our best analogues for the rocks that formed Earth, so the hydrogen concentrations in these "dry" rocks hint at the possible presence of water during Earth’s formation.

We compared the Earth composition and that of enstatite chondrites by looking at the amounts of various isotopes (atoms of the same element but containing different numbers of neutrons). We find that, although enstatite chondrites do not contain hydrated minerals, they do contain small amounts of hydrogen with an isotopic ratio consistent with the Earth's. Hydrogen is thought to have been present in trace amounts (<0.1%) in the minerals and organic compounds that agglomerated to form enstatite chondrites, explaining where most of the water contained in Earth's mantle and in part of the oceans comes from. The majority of Earth's water (more precisely its elements, hydrogen and oxygen) may thus have been present from the beginning.

What are the consequences of a local origin of water?

This does not tell us when the oceans appeared on Earth's surface, but we now know that Earth's water was not necessarily delivered by hydrated bodies that formed very far from the sun. However, we do not yet understand in what form(s) and by what process hydrogen was incorporated and stored in rocks of the inner solar system.

Read more: Why is the Earth blue?

The presence of hydrogen in inner solar system rocks is particularly important because it could have been a water source for the other rocky planets (Mercury, Venus, and Mars). Similar rocks could then represent a source of water for planets orbiting other suns, a condition to develop life, at least life as we know it.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher. 

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Joshua Davies, Professor, Sciences de la Terre et de l'atmosphère, Université du Québec à Montréal (UQAM)

Brenda Chung Rocha, Professor, Geosciences, Universidade de São Paulo

Nicolas Greber, Assistant professor, Geochemistry, Université de Berne

Mass extinctions are times in Earth’s past when large proportions of life suddenly and catastrophically died. These have occurred periodically over the past 550 million years. The exact causes of these extinctions are not fully understood, but there appears to be a remarkable coincidence between mass extinctions and huge volcanic eruptions that form large igneous provinces (LIPs).

LIPs are massive volcanoes that produce millions of cubic kilometres of basaltic magma in a very short time. They are much bigger in scale than the famous super eruptions — like the Yellowstone caldera supervolcano — which typically release less than 5,000 cubic kilometres of magma.

The magma from LIPs can release enough gases during eruption, such as carbon dioxide (a greenhouse gas) or sulphur-based compounds, to change the climate. This climate change in turn affects the composition of the oceans and quickly leads to the death of life on Earth.

While huge volcanic eruptions have been linked to mass extinctions on Earth, our research shows that one of the world’s largest known LIPs may have had no effect on climate or caused any extinctions. Before our study, the precise age of the LIP was not really known; with our improved dataset and higher precision analysis, we were able to show that these things did not occur at the same time.

Not just eruptions

Research has also suggested that basalt from LIPs, which intrude into the crust, can heat up and change — metamorphose — sedimentary rocks that are rich in volatiles, compounds that vaporize readily. This metamorphism can release huge amounts of gases such as methane and sulphur dioxide from the sediments, which also change the climate — leading to mass extinctions.

Both of these mechanisms have been blamed for causing the climate change which resulted in mass extinctions. However, there are also cases of LIPs that don’t seem to cause mass extinctions and also extinctions that have no apparent LIP. The relationship between these huge LIP volcanic eruptions and mass extinctions may not be as clear as previously thought. Disentangling the exact mechanisms involved has been the focus of numerous scientific studies.

One extremely important factor to consider is the exact age of the LIP relative to the mass extinction. If the ages of the climate change, associated mass extinction and the LIP do not overlap, then the volcanism is not the cause.

Brazilian eruption

To investigate whether one of the world’s largest LIPs caused massive climate change and a mass extinction, our research team generated highly precise ages for the Paraná-Etendeka LIP in Brazil. We dated the mineral zircon that crystallized within the erupted lava flows using the U-Pb system allowing us to precisely determine the eruption age of the lavas. This technique produces precise and accurate ages for LIPs.

Numerous studies had linked this LIP to a mass extinction event found in the oceans. The first thing we wanted to know was when did this LIP erupt, and for how long. Once we had this information, we could determine if it occurred at exactly the same time as the mass extinction event.

Our study focused on the Paraná Magmatic Province — the South American portion of the LIP in Brazil — which is by far the largest, and produced approximately one million cubic kilometres of magma.

When this LIP erupted, 140 million years ago, South America and Africa were connected and were part of the Gondwana supercontinent. This LIP erupted in Brazil and Namibia, when both of these areas were neighbours before the opening of the Southern Atlantic Ocean.

Read more: How the Earth's last supercontinent broke apart to form the world we have today

Many studies have suggested that this LIP caused global climate change which led to a small mass extinction and also a reduction in the oxygen concentration in the oceans. This period is called the Valanginian event.

No environmental effects

Our research shows that that the Paraná LIP erupted extremely quickly, around one million years after the mass extinction and so it is unlikely to have been the cause. There is one older part of the Paraná LIP that we did not work on which could have caused the Valanginian event. But most LIPs erupt over a very short period of time, so it is unlikely that the older portion is more than one million years older than the rest of the province.

We also did not work on the Etendeka part of the province in Namibia. However this part of the province is extremely small in comparison to the South American part, and we expect that it erupted coincidentally with the Paraná, although it may have continued to erupt for longer (and therefore may be younger).

Our study of the Paraná LIP proves that the eruption of huge volumes of LIP magma alone may not be enough to cause mass extinctions. The question that remains is why this huge eruption of magma had almost no effect on the climate; our theory is that the lack of volatile-rich sediments around the Paraná LIP meant that no extra volatiles were released due to metamorphism during the positioning, or emplacement, of the LIP. Perhaps the metamorphism of sediments by LIP magmas, and the gas released associated with this, is the main driver of climate change leading to mass extinctions?

Earth’s largest mass extinction event occurred at the end of the Permian period, coinciding with the eruption of the Siberian Traps LIP. This LIP intruded large volatile rich sedimentary basins which likely caused the release of massive amounts of volatile compounds.

Our findings for the Paraná LIP also depend on the age of the Valanginian event. Currently, the age estimation for this event is based on cyclic analysis of ocean sediments, but it is possible that with greater precision, we may find it overlaps with the Paraná LIP. While huge volcanic eruptions have been linked to mass extinctions on Earth, our research shows that one of the world’s largest known LIPs may have had no effect on climate or caused any extinctions. But for now, it seems that the Paraná LIP had almost no environmental effect on our planet.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher. 

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Annika Seppälä, Senior Lecturer in Geophysics, University of Otago

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz

When the Sun ejects solar particles into space, how does this affect the Earth and climate? Are clouds affected by these particles?

When we consider the sun's influence on Earth and our climate, we tend to think about solar radiation. We are acutely aware of the skin-burning dangers of ultraviolet, or UV, radiation.

But the sun is an active star. It also continuously releases what is known as "solar wind," made up of charged particles, largely protons and electrons, that travel at speeds of hundreds of kilometres per hour.

Some of these particles that reach Earth are guided into the polar atmosphere by our magnetic field. As a result, we can see the southern lights, aurora australis, in the southern hemisphere, and the northern equivalent, aurora borealis.

This visible manifestation of solar particles entering Earth's atmosphere is a constant reminder there is more to the sun than sunlight. But the particles have other effects as well.

Read more: Why is the sun's atmosphere so hot? Spacecraft starts to unravel our star's mysteries

Solar particles and ozone

When solar particles enter the atmosphere, their high energies ionise neutral atmospheric nitrogen and oxygen molecules, which make up 99% of the atmosphere. This "energetic particle precipitation," named because it's like a rain of particles from space, is a major source of ionisation in the polar atmosphere above 30 km altitude — and it sets off a chain of reactions that produces chemicals that facilitate the destruction of ozone.

The impact of solar particles on atmospheric ozone was first observed in 1969. Since the early 2000s, thanks to new kinds of satellite observations, we have seen growing evidence that solar particles play an important part in influencing polar ozone. During particularly active times, when the Sun releases large amounts of particles into space, up to 60% of ozone at altitudes above 50 km can be depleted. The effect can last for weeks.

Lower down in the atmosphere, below 50 km, solar particles are important contributors to the year-to-year variability in polar ozone levels, often through indirect pathways. Here, solar particles again contribute to ozone loss, but a recent discovery showed they also help curb some of the depletion in the Antarctic ozone hole.

How ozone affects the climate

Most of the ozone in the atmosphere resides in a thin layer at altitudes of 20-25 km — the "ozone layer."

But ozone is everywhere in the atmosphere, from the Earth's surface to altitudes above 100 km. It is a greenhouse gas and plays a key role in heating and cooling the atmosphere, which makes it critical for climate.

In the Southern Hemisphere, changes in polar ozone are known to influence regional climate conditions.

Its depletion above Antarctica had a cooling effect, which in turn pulled the westerly wind jet that circles the continent closer. As the Antarctic hole recovers, this wind belt can meander further north and affect rainfall patterns, sea-surface temperatures and ocean currents. The Southern Annular Mode describes this north-south movement of the wind belt that circles the southern polar region.

Ozone is important for future climate predictions, not only in the thin ozone layer, but throughout the atmosphere. It is crucial we understand the factors that influence ozone variability, be it man-made or natural like the sun.

The sun's direct influence

The link between solar particles and ozone is reasonably well established, but what about any direct effects solar particles may have on the climate?

We have observational evidence that solar activity influences regional climate variability at both poles. Climate models also suggest such polar effects link to larger climate patterns (such as the Northern and Southern Annular Modes) and influence conditions in mid-latitudes.

The details are not yet well understood, but for the first time the influence of solar particles on the climate system will be included in climate simulations used for the upcoming Intergovernmental Panel on Climate Change (IPCC) assessment.

Read more: Solar weather has real, material effects on Earth

Through solar radiation and particles, the Sun provides a key energy input to our climate system. While these do vary with the Sun’s 11-year cycle of magnetic activity, they can not explain the recent rapid increase in global temperatures due to climate change.

We know rising levels of greenhouse gases in the atmosphere are pushing up Earth’s surface temperature (the physics have been known since the 1800s). We also know human activities have greatly increased greenhouse gases in the atmosphere. Together these two factors explain the observed rise in global temperatures.

What about clouds?

Clouds are much lower in the atmosphere than where most solar particles penetrate. Particles know as galactic cosmic rays (coming from the centre of our galaxy rather than the sun) may be linked to cloud formation.

It has been suggested cosmic rays could influence the formation of condensation nuclei, which act as "seeds" for clouds. But recent research at the CERN nuclear research facility suggests the effects are insignificant.

This doesn’t rule out some other mechanisms for cosmic rays to affect cloud formation, but thus far there is little supporting evidence.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher. 

This year, our planet has been setting records with extreme wildfires, storms and spiking temperatures. Now, it's set another record: The hottest September since record-taking began over 30 years ago.

The globe was 0.05 degrees Celsius (0.09 degrees Fahrenheit) warmer this September than it was in September 2019, the previous record-holder, according to a statement from the Climate Change Service, which is part of the European Union's Earth Observation Program known as Copernicus.

Many countries experienced higher-than-average temperatures but there were "unusually high" temperatures off the coast of northern Siberia, in the Middle East and in parts of South America and Australia, according to the statement. Europe has also had its warmest September ever, with temperatures about 0.2 C (0.36 F) higher than the previous warmest September of 2018.

Related: 10 signs Earth's climate is off the rails

Both January and May have also broken temperature records this year. 

In June, a town in Siberia recorded a temperature of 100.4 F (38 C), the hottest temperature ever recorded above the Arctic Circle, Live Science previously reported. Winter and spring in Siberia were also "unusually warm," with temperatures up to 18 F (10 C) higher than normal in May, according to the statement. In August, California's Death Valley hit 130 F (54.4 C), its hottest temperature in over a century and one of the hottest temperatures in the world, according to another Live Science report.

Los Angeles County recorded its highest temperature ever in the beginning of September at 121 F (49.4 C), according to another Live Science report. 

Warming has also led to weather more intense weather events. This year, wildfires in California have burned a record-breaking 4 million acres (1.6 million hectares), and the wildfire season is far from over. In fact, the area burned by wildfires in California has been increasing each year since 1950, according to California Environmental Protection's Agency's Air Resources Board, Live Science previously reported.

September also recorded the second lowest amount of sea ice in the world, according to the statement. "This is not totally unexpected, as sea ice extent has been declining for several decades, and September is the month that tends to show the lowest values for the year," officials with the Copernicus Climate Change Service wrote in the statement.

The data that's used to monitor surface air temperatures is part of a dataset known as the "ERA5" which has data reaching back to 1979, according to the statement. But the entire ERA5 dataset starting in 1950 will be available in 2020, according to the European Centre for Medium-Range Weather Forecasts.

Originally published on Live Science.

Wildfires are burning the West Coast, hurricanes are flooding the Southeast — and some of those storms are rising from the dead. 

"Zombie storms," which regain strength after initially petering out, are the newest addition to the year 2020. And these undead weather anomalies are becoming more common thanks to climate change.

"Because 2020, we now have Zombie Tropical Storms. Welcome back to the land of the living, Tropical Storm #Paulette," the National Weather Service wrote on Twitter on Tuesday (Sept. 22).

Earlier this month, Tropical storm Paulette formed in the Atlantic Ocean and made landfall in Bermuda as a Category 1 hurricane, according to CNN. It then strengthened over land into a Category 2 hurricane, before weakening and dying off five and half days later. 

Related: The reality of climate change: 10 myths busted

But then, Paulette opened her frightening eye once again. She wasn't gone. 

Paulette regained strength and became a tropical storm once more about 300 miles (480 kilometers) away from the Azores Islands on Monday (Sept. 21), according to CNN. The term "zombie storm" is new, and though the phenomenon has been recorded before, it is thought to be rare. 

But zombie storms are going to happen more often, said Donald Wuebbles, a professor of atmospheric sciences at the University of Illinois at Urbana-Champaign. And as with other natural disasters that have been intensifying in recent years, such as wildfires and hurricanes, climate change and rapid global warming are to blame. 

There has been an "extreme amount of heating of the Gulf (of Mexico), particularly in some of the ocean areas off of the Carribean," Wuebbles told Live Science. The Gulf of Mexico, where many hurricanes gain strength before hitting the U.S., is particularly vulnerable to global warming because the gulf waters are very shallow — and thus heat up easily, Wuebbles said.

Atlantic Ocean storms typically form in warmer parts of the ocean near Africa, due to a combination of atmospheric and ocean conditions. They then "race across" the ocean toward the Americas, Wuebbles said. Hurricanes need warm water and moist air to form, according to the University Corporation for Atmospheric Research. Storms grow if there's a continuous supply of energy from warm water and air, and they weaken when they move over cooler waters or over land.

"If they're not so strong, in the past, they would just die out," over the Atlantic, Wuebbles said. But now, they reach warm water in the Carribean region and pick up energy again, he added. This is also true for storms that haven't died out yet. For instance, about a month ago, Hurricane Laura strengthened overnight from a Category 1 storm to a Category 4 storm because it picked up energy from warm water in the Gulf, Wuebbles said. 

With a warming globe, "storms are likely to become more intense," he added. That means the idea of "zombie storms" may be here to stay. 

Thankfully Paulette seems to have become a post-tropical cyclone once more and will die out soon, according to the National Hurricane Center. 

Originally published on Live Science.

Penguins might be good at hiding from humans, but they can't hide their poop from the giant satellites circling our planet. 

New imagery revealed penguin poop stains on the white blankets of the coldest continent. And those dark spots suggest that there are nearly 20% more emperor penguin colonies in Antarctica than previously thought. 

This is both "good and bad news," as all of these new colonies are located in areas likely to be highly vulnerable to climate change, according to the study, published on Aug. 4 in the journal Remote Sensing in Ecology and Conservation. 

It's not easy to count just how many emperor penguins live on Antarctica as the animals typically breed in very frigid, remote and difficult to reach places. To get around this, for the past decade, scientists with the British Antarctic Survey (BAS) have been searching for penguins indirectly by looking for poop stains in satellite imagery.

Related: In photos: The emperor penguin's beautiful and extreme breeding season

In the new study, scientists analyzed images taken in 2016, 2018 and 2019 by the European Space Agency's Copernicus Sentinel-2 satellites. They reviewed the images for brown pixels, which represent guano stains. 

The images revealed eight new emperor penguin colonies — and confirmed the existence of three others previously identified — bringing the continent's total to 61 colonies. But most of the colonies were so small, the researchers had to use multiple images to confirm they existed, according to the study. Those 11 new colonies increase the known emperor penguin population by 5% to 10%, or up to 55,000 additional birds, bringing the total population of the world's tallest living penguin to somewhere between 531,000 and 557,000, the study found. 

"Whilst it's good news that we've found these new colonies, the breeding sites are all in locations where recent model projections suggest emperors will decline," Phil Trathan, the head of conservation biology at BAS said in a statement. "Birds in these sites are therefore probably the 'canaries in the coal mine' — we need to watch these sites carefully as climate change will affect this region."

Almost all emperor penguin colonies depend on stable sea ice anchored to the land for breeding, according to the study. And this land-anchored ice needs to remain stable for around 9 months from when they breed to when their chicks fledge. 

Previous projections have suggested that climate change and melting ice is likely going to spark a decline in emperor penguin populations, according to the statement. Even if global temperature increases only by 2.7 degrees Fahrenheit (1.5 degrees Celsius) — which climate scientists think is the best-case scenario — Antarctica's population of emperor penguins will decrease by at least 31% over the next three generations, one 2019 study in the journal Global Change Biology found. 

Some of these colonies were located far offshore, some up to 112 miles (180 kilometers) off the coast, on sea ice formed around icebergs that had grounded in shallow water, according to the BAS. This was the first time emperor penguins were found to breed so far from  shore and that means there are potential breeding habitats in places we don't know of, the authors wrote. However, "these areas away from the coast are more northerly, they will be in warmer areas and therefore will be more likely to be susceptible to early sea ice loss," the researchers wrote in the study.

This isn't the only time scientists have found penguins from their poop. Two years ago, another group uncovered a previously unknown supercolony of 1.5 million Adélie penguins on the Antarctic Peninsula's Danger Islands, by finding poop stains in satellite images, according to a previous Live Science report. These Adélie penguins had somehow thrived despite climate change, while their counterparts on the western side of the Antarctic Peninsula had already had population declines.

Originally published on Live Science.

Humanity has been sending spacecraft to Mars since the Soviet Union launched Marsnik 1 on Oct. 10, 1960 (though the craft failed to reach its goal). To mark the upcoming Red Planet arrival — NASA's Perseverance rover — Space.com has taken a look back at some of the most spectacular successes (and failures) in humanity's bid to reach the Red Planet.

Mars 2 Orbiter and Lander

The Soviet Union launched the Mars 2 Orbiter on May 19, 1971. The spacecraft arrived at Mars and released its lander on November 27, 1971. Unfortunately, the lander crashed onto the Martian surface. However, it still represents the first human-made object on Mars. 

Mariner 9

NASA sent the Mariner 9 towards Mars on May 30, 1971. Mariner 9 arrived at Mars on Nov. 14, 1971, where it became the first spacecraft to orbit another planet. Mariner 9 was deactivated on Oct. 27, 1972, but it is expected to remain in orbit until 2022.  

Viking 1 & 2

NASA's Viking 1 and Viking 2 spacecraft each consisted of an orbiter and lander. Viking 1 launched on Aug. 20, 1975, and after a month of searching for landing sites, sent the Viking 1 Lander to the surface of Mars on July 20, 1976 — the first successful landing on Mars. Viking 2 spacecraft launched Sept. 9, 1975, and its lander touched down on Sept. 3, 1976. 

The Viking craft proved to be a huge success, and provided the most complete view of Mars at the time, producing over 50,000 photos of the planet.

Mars Pathfinder Spacecraft and Sojourner Rover

NASA launched the Pathfinder spacecraft on Dec. 4, 1996, and it arrived at Mars on July 4, 1997. Sojourner Rover emerged from Pathfinder on July 6, making it the first wheeled vehicle on Mars. Sojourner was the first rover to operate on another planet. Only two feet in length (63 cm), the rover possessed six wheels. The final contact with Pathfinder was on Sept. 27, 1997. 

Japan's Nozomi Mars Probe

Japan launched the Nozomi spacecraft, the nation's first planetary mission, on July 4, 1998. The orbiting mission was designed to study the Martian upper atmosphere and its interaction with the solar wind. However, on December 20, 1998, a malfunctioning valve left the spacecraft unable to head to Mars as planned. 

An amended plan to reach Mars also failed, and efforts to save the mission ended on Dec. 9, 2003. In the words of the Japan Aerospace Exploration Agency: "NOZOMI became an artificial planet that flies forever in orbit around the sun near that of Mars." 

Mars Odyssey

The 2001 Mars Odyssey spacecraft launched on April 7, 2001. It arrived in orbit around Mars on October 24, 2001. Its planned mission ended in 2004, but it continues in operation at the time of this writing and remains NASA's longest-operating spacecraft at Mars. It broke the record for the longest-serving spacecraft at Mars on Dec. 15, 2010.

Spirit and Opportunity Rovers

NASA's golf cart-size Spirit and Opportunity Rovers launched to Mars in 2003 and used giant airbags to cushion their landings in January 2004. The amazingly long-lived rovers far outstripped their planned missions of 90 Martian solar days. Spirit plugged away until April 2009, when it got stuck in deep sand. It went silent on March 22, 2010 and was declared dead a year later.

Opportunity is also no longer in commission. But, while the rover was supposed to last just 90 days on the Red Planet's surface, it lasted an incredible 5,111 days until its last transmission. The rover lasted from 2004 up until the middle of 2018 when it lost communication after a global dust storm. 

Europe's Mars Express and Beagle 2 Lander

The European Space Agency (ESA) launched its first planetary explorer, the Mars Express spacecraft, on June 3, 2003. On Dec. 19, 2003, the Beagle 2 Lander was released. Unfortunately, contact with the lander was broken and it was subsequently declared lost. Mars Express orbiter completed its mission in 2005, and continues to operate at the time of this writing, providing many images from its High Resolution Stereo Camera (HRSC).

Phoenix Mars Lander

NASA's Phoenix lander launched on Aug. 4, 2007, and landed near the Martian north pole on May 25, 2008. It completed its mission, including verifying the presence of water-ice in the Martian subsurface. However, the lander was not designed to withstand a polar Martian winter. The mission ended on May 24, 2010. 

Mars Reconnaissance Orbiter

NASA's Mars Reconnaissance Orbiter (MRO) lifted off on Aug. 12, 2005, and arrived at the Red Planet in March 2006. It completed its two-year primary science phase, and is in the extended phase of its mission, where it continues to return copious amounts of information. 

Phobos-Grunt and China's 1st Mars Probe

Russia's Phobos-Grunt mission ambitiously hoped to return samples of Mars' moon Phobos to Earth. The two-stage Zenit rocket bearing the mission (also carrying the Chinese Mars orbiter Yinghuo-1) launched on Nov. 9, 2011. 

However, the spacecraft failed to achieve the proper orientation to proceed to Mars, and ground controllers were unable to correct the positioning. It is believed that the spacecraft returned to Earth in an uncontrolled re-entry on Jan. 15, 2012, falling somewhere in the Pacific Ocean, though no remnants have been discovered. 

Curiosity Rover

NASA's largest rover to date, the Mars Science Laboratory, also known as Curiosity, launched on Nov. 26, 2011 and aced a harrowing landing on Mars on Aug. 5, 2012. Curiosity rover is big as a car and contains a nuclear reactor for power. 

Its landing mechanism, the "sky crane," represented a new way of delivering a payload onto the Martian surface. For the first time, this rover possesses a laser with which to vaporize rock and conduct experiments. 

InSight

NASA's InSight Mars lander launched to the Red Planet on May 5, 2018 and successfully landed at at the Martian Elysium Planitia on the planet's surface on Nov. 26, 2018. The stationary probe, whose name stands for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is designed to study Mars' interior. 

Tianwen-1

Tianwen-1 is China's second attempted Mars mission and the country's first-ever Mars mission completed alone (the country worked to send the orbiter Yinghuo-1 into orbit around Mars and, while the mission failed to reach the Red Planet, it launched aboard Russia's Mars mission Fobos-Grunt). 

The mission is an orbiter/lander/rover combination that is scheduled to take off July 23, 2020. With the success of this mission, China will become the third country to land on the planet. 

UAE Hope

The United Arab Emirates is scheduled to launch its first-ever interplanetary mission, known as the Hope Mars mission this summer. The launch was delayed from its original July 14 launch date. 

The mission will launch from Tanegashima Space Center in Japan aboard an H-IIA rocket. The $200 million spacecraft, also called the Emirates Mars Mission, is set to arrive at Mars in early 2021 after a seven month journey. Hope is designed to orbit over the planet's equator for a full Mars year (about two Earth years) to study Mars' atmosphere and weather. 

Perserverance

NASA's Perseverance rover, originally known as the Mars 2020 rover, will search for signs of ancient life on the Red Planet. The rover is set to launch this summer no earlier than July 30. The car-sized rover holds a number of science experiments and tools including the Mars helicopter Ingenuity. 

The spectacular solar storms that paint the polar skies in beautiful greens and pinks have a darker side: They have the power to wreak havoc on our electrical grid, communication systems and satellites. Now, a new study suggests that the source of these solar storms is much closer to our planet than previously thought.

Earth is shielded by a protective bubble known as the magnetosphere which blocks harmful solar radiation. But when the sun occasionally emits high-speed streams of radiation — and, with it, intense magnetic field lines — they can strongly interact with our planet's own magnetic field.

As this solar wind hits the magnetosphere, the two sets of magnetic field lines become entangled. This interaction generates heat and accelerates the charged particles — ions and electrons— brought in by the solar wind, temporarily weakening the planet's magnetic field and creating powerful magnetic storms that appear to us as auroras.

Related: Aurora Photos: Northern Lights Dazzle in Night-Sky Images

But because these storms are rare, and there aren't enough satellites to observe them, it's not clear exactly where and how this reconnection of magnetic field lines happened, the study's researchers said in a statement. 

To figure that out, the researchers used observations from NASA's Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellites. During solar storms, these satellites  sit at Earth's magnetotail — the part of the magnetosphere on the side of the planet not facing the sun — which becomes elongated by the solar wind. The researchers found that this magnetic reconnection — the event that sparks magnetic storms — can occur much closer to our planet than previously thought: about three to four Earth diameters away, according to the statement. 

What's more, a weather satellite in a near-Earth orbit (or geosynchronous orbit) detected energized electrons following the storm, suggesting that the reconnection event prompted ions and electrons to accelerate to high energies. The electrons that flow toward the planet carry energy along magnetic field lines to create the auroras we see. 

This acceleration can be hazardous to the hundreds of satellites moving in geosynchronous orbit and also can be harmful to human DNA, thereby posing a risk to astronauts, according to the statement. 

Moreover, solar storms can impact Earth-dwellers in significant ways. In 1921, for example, a magnetic storm disrupted telegraph communications and caused power outages that led to the burning of a train station in New York City, according to the statement.  

"By studying the magnetosphere, we improve our chances of dealing with the greatest hazard to humanity venturing into space: storms powered by the sun," lead author Vassilis Angelopoulos, a professor of space physics at UCLA, said in the statement. These findings might help astronauts and Earth-dwellers to better prepare for dangerous solar weather.

The findings were published Jan. 13 in the journal Nature Physics.

• In Images: Rising 'Phoenix' Aurora and Starburst Galaxies Light Up the Skies
• Rare Photo: Auroras on Uranus Spotted by Hubble Telescope
• Aurora Photos: See Breathtaking Views of the Northern Lights

Originally published on Live Science.

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

Paulo de Souza, Professor, Griffith University

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz

The recipe for the temperature of a planet's surface has four major ingredients: atmospheric composition, atmospheric density, water content (from oceans, rivers and air humidity) and distance from the Sun. There are other ingredients, including seasonal effects or the presence of a magnetosphere, but these work more like adding flavour to a cake.

When we look at Earth, the balance of these ingredients makes our planet habitable. Changes in this balance can result in effects that can be felt on a planetary scale. This is exactly what is happening with the increase of greenhouse gases in the atmosphere of our planet.

Increased concentrations of carbon dioxide, methane, sulphur hexafluoride and other gases in the atmosphere have been raising the temperature of our planet's surface gradually and will continue to do so for many years to come.

Read more: Climate explained: why carbon dioxide has such outsized influence on Earth's climate

As a consequence, places covered in ice start melting and extreme weather events become more frequent. This poses a growing challenge for us to adapt to this new reality.

Small concentration, big effect

It is surprising to realise how little the concentration of carbon dioxide (CO₂) and other greenhouse gases has to change to cause such a shift in our climate. Since the 1950s, we have raised CO₂ levels in the atmosphere by a fraction of a percent, but this is already causing several changes in our climate.

This is because CO₂ represents a tiny part of Earth’s atmosphere. It is measured in parts per million (ppm) which means that for every carbon dioxide molecule there are a million others. Its concentration is just 0.041%, but even a small percentage change represents a big change in concentration.

We can tell what Earth’s atmosphere and climate were like in the distant past by analysing bubbles of ancient air trapped in ice. During Earth’s ice ages, the concentration of carbon dioxide was around 200ppm. During the warmer interglacial periods, it hovered around 280ppm, but since the 1950s, it has continued to rise relentlessly. By 2013, CO₂ levels surpassed 400ppm for the first time in recorded history.

This rise represents almost a doubling in concentration, and it clear that, in the recipe for Earth's surface temperature, carbon dioxide and other greenhouse gases are to be used in moderation.

The role of water

Like flour for a cake, water is an important ingredient of the Earth's surface. Water makes temperature move slowly. That's why the temperatures in tropical rainforests does not change much, but the Sahara desert is cold at night. Earth is rich in water.

Let's have a look at our solid planets. Mercury is the closest planet to the Sun, but it has a very thin atmosphere and is not the warmest planet. Venus is very, very hot. Its atmosphere is rich in carbon dioxide (over 96%) and it is very dense.

The atmosphere of Mars is also rich in carbon dioxide (above 96%), but it is extremely thin (1% of Earth's atmosphere), very dry and located further away from the Sun. This combination makes the planet an incredibly cold place.

The absence of water makes the temperature on Mars change a lot. The Mars exploration rovers (Spirit at Gusev Crater and Opportunity at Meridiani Planun) experienced temperatures ranging from a few degrees Celsius above zero to minus 80℃ at night: every single Martian day, known as sol.

Read more: Curious Kids: What are some of the challenges to Mars travel?

Terraforming or terra fixing

One of the interesting challenges we face while building space payloads, like we do at Griffith University, is to build instruments that can withstand such a wide temperature range.

I love conversations about terraforming. This is the idea that we could fly to a planet with an unbreathable atmosphere and fix it by using some sort of machine to filter nasty gases and release good ones we need to survive, at the correct amount. That is a recurrent theme in many science fiction films, including Aliens, Total Recall and Red Planet.

I hope we can fix our own atmosphere on Earth and reduce our planet's fever.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher.  

Another autumn, more fires, more refugees and incinerated homes. For California, flames have become the colors of fall.

Free-burning fire is the proximate provocation for the havoc, since its ember storms are engulfing landscapes. But in the hands of humans, combustion is also the deeper cause. Modern societies are burning lithic landscapes - once-living biomass now fossilized into coal, gas and oil - which is aggravating the burning of living landscapes.

The influence doesn't come only through climate change, although that is clearly a factor. The transition to a fossil fuel civilization also affects how people in industrial societies live on the land and what kind of fire practices they adopt.

Even without climate change, a serious fire problem would exist. U.S. land agencies reformed policies to reinstate good fire 40 to 50 years ago, but outside a few locales, it has not been achievable at scale.

What were lithic landscapes have been exhumed and no longer only underlie living ones. In effect, once released, the lithic overlies the living and the two different kinds of burning interact in ways that sometimes compete and sometimes collude. Like the power lines that have sparked so many wildfires, the two fires are crossing, with lethal consequences.

Fire as a framework

As a historian of fire, I know that no single factor drives it. Flames synthesize their surroundings. Fire is a driverless car that barrels down the road integrating whatever is around it.

Sometimes it confronts a sharp curve called climate change. Sometimes it's a tricky intersection where townscape and countryside meet. Sometimes it's road hazards left from past accidents, like logging slash, invasive grasses or postburn environments.

Climate change acts as a performance enhancer, and understandably, it claims most of the attention because it's global and its reach extends beyond flames to oceans, mass extinctions and other knock-on effects. But climate change is not enough by itself to account for the plague of megafires. Climate integrates many factors, and so does fire. Their interplay makes attribution tricky.

Instead, consider fire in all its manifestations as the informing narrative. The critical inflection in modern times occurred when humans began to burn fossilized rather than living biomass. That set into motion a "pyric transition" that resembles the demographic transition which accompanies industrialization as human populations first expand, then recede. Something similar happens with the population of fires, as new ignition sources and fuels become available while old ones persist.

In the U.S., the transition sparked a wave of monster fires that rode the rails of settlement — fires an order of magnitude larger and more lethal than those of recent decades. Land clearing and logging slash fed serial conflagrations, which blew up in the late 19th and early 20th centuries, the waning decades of the Little Ice Age.

It was a period of flame-catalyzed havoc that inspired state-sponsored conservation and a determination to eliminate free-burning flame. Led by foresters, the belief spread that fire on landscapes could be caged, as it was in furnaces and dynamos.

Eventually, as technological substitution (think of replacing candles with lightbulbs) and active suppression reduced the presence of open flame, the population of fires fell to the point where fire could no longer do the ecological work required. Meanwhile, society reorganized itself around fossil fuels, adapting to the combustion of lithic landscapes and ignoring the fire latent in living ones.

Now the sources overload the sinks: Too much fossil biomass is burned to be absorbed within ancient ecological bounds. Fuels in the living landscape pile up and rearrange themselves. The climate is unhinged. When flame returns, as it must, it comes as wildfire.

Welcome to the Pyrocene

Widen the aperture a bit, and we can envision Earth entering a fire age comparable to the ice ages of the Pleistocene, complete with the pyric equivalent of ice sheets, pluvial lakes, periglacial outwash plains, mass extinctions, and sea level changes. It's an epoch in which fire is both prime mover and principal expression.

Even climate history has become a subset of fire history. Humanity's firepower underwrites the Anthropocene, which is the outcome not just of human meddling but of a particular kind of meddling through humanity's species monopoly over fire.

The interaction of these two realms of fire has not been much studied. It's been a stretch to fully include human fire practices within traditional ecology. But industrial fire, unlike landscape fires, is solely a product of human finagling, and so has stood outside the bounds of ecological science. It's as though the intellectual sink for understanding can no more hold the new realm of burning than nature can its emissions.

Yet in humanity — the keystone species for fire on Earth — those two arenas of earthly burning, like smoke from separate fires drawn into a single convective column, are merging. Their give and take is reshaping the planet.

In the developed world, industrial combustion arranges agriculture, built environments, peri-urban settings and reserves for wildlands — all the stuff available for landscape fire. Societies even fight landscape fire with the counterforce of industrial fire in the form of pumps, engines, aircraft and vehicles to haul crews. The interaction of the two realms of fire determines not only what gets burned, but also what needs to be burned and isn't. It changes the road fire drives down.

Add up all the effects, direct and indirect — the areas burning, the areas needing to be burned, the off-site impacts with damaged watersheds and airsheds, the unraveling of biotas, the pervasive power of climate change, rising sea levels, a mass extinction, the disruption of human life and habitats — and you have a pyrogeography that looks eerily like an ice age for fire. You have a Pyrocene. The contours of such an epoch are already becoming visible through the smoke.

If you doubt it, just ask California.

[Like what you've read? Want more? Sign up for The Conversation's daily newsletter.]

This article was originally published at The Conversation. The publication contributed the article to Live Science's Expert Voices: Op-Ed & Insights.

There's a lost continent hidden below southern Europe. And researchers have created the most detailed reconstruction of it yet.

The lost continent "Greater Adria" emerged about 240 million years ago, after it broke off from Gondwana, a southern supercontinent made up of Africa, Antarctica, South America, Australia and other major landmasses, as Science magazine reported. 

Greater Adria was large, extending from what is now the Alps all the way to Iran, but not all of it was above the water. That means it was likely a string of islands or archipelagos, said lead author Douwe van Hinsbergen, the chair in global tectonics and paleogeography in the Department of Earth Sciences at Utrecht University in the Netherlands. It would have been a "good scuba diving region."

Related: In Images: How North America Grew As a Continent

Hinsbergen and his team spent a decade collecting and analyzing rocks that used to be part of this ancient continent. The mountain belts where these Greater Adrian rocks are found span about 30 different countries, Hinsbergen told Live Science. "Every country has their own geological survey and their own maps and their own stories and their own continents," he said. With this study, "we brought that all together in one big picture." 

Earth is covered in large tectonic plates that move relative to each other. Greater Adria belonged to the African tectonic plate (but was not a part of the African continent, since there was an ocean between them), which was slowly sliding beneath the Eurasian tectonic plate, in what is now southern Europe. 

Around 100 million to 120 million years ago, Greater Adria smashed into Europe and began diving beneath it — but some of the rocks were too light and so did not sink into Earth's mantle. Instead, they were  "scraped off" — in a way that's similar to what happens when a person puts their arm under a table and then slowly moves it underneath: The sleeve get crumpled up, he said. This crumpling formed mountain chains such as the Alps. It also kept these ancient rocks locked in place, where geologists could find them.

Hinsbergen and his team looked at the orientation of tiny, magnetic minerals formed by primeval bacteria in these rocks. The bacteria make these magnetic particles in order to orient themselves with the Earth's magnetic field. When the bacteria die, the magnetic minerals are left behind in the sediment, Hinsbergen said. 

With time the sediment around them turns into rock, freezing them in the orientation they were in hundreds of millions of years ago. Hinsbergen and his team found that in many of these regions, the rocks had undergone very large rotations.

What's more, Hinsbergen's team pieced together large rocks that used to belong together, such as in a belt of volcanoes or in a big coral reef. Moving faults scattered the rocks "like pieces of a broken plate," he said.

It's like a big jigsaw puzzle, Hinsbergen said. "All the bits and pieces are jumbled up and I spent the last 10 years making the puzzle again." From there, they used software to create detailed maps of the ancient continent and confirmed that it moved northward while twisting slightly, before colliding with Europe. 

After many years working in the Mediterranean region, Hinsbergen has now moved on to reconstruct the lost plates in the Pacific Ocean. "But I'll probably return — probably in 5 or 10 years from now when a whole bunch of young students will demonstrate that parts are wrong," Hinsbergan said. "Then I'll come back and see if I can fix it."

The findings were published Sept. 3 in the journal Gondwana Research.

• The 25 Most Mysterious Archaeological Finds on Earth
• Photo Timeline: How the Earth Formed
• Photos: The World's Weirdest Geological Formations

Originally published on Live Science.

An invisible substance permeates the universe, altering the paths of stars and galaxies.

This so-called dark matter exerts a gravitational pull, yet never interacts with light. No one knows what it's made of and it has been impossible to detect until now. But a new theory could finally provide a way to test for dark matter. [The 11 Biggest Unanswered Questions About Dark Matter]

Dark matter might be made up of weird half-magnets, theoretical physicists from the University of California, Davis, said at a presentation on June 6 at the Planck 2019 conference in Granada, Spain. And by turning on a really powerful (as-of-yet nonexistent) electron microscope, we might finally be able to detect them.

But not all physicists are convinced.

"I think it's neat, but not very promising," said Sabine Hossenfelder, a research fellow at the Frankfurt Institute for Advanced Studies, who was not a part of the study. "There are infinitely many particles you can invent that may make up dark matter." This is just another one of them, she added.

"For each of these particles you can do lots of calculations, publish papers and think up experiments, which you can then try to get funding for," she said. "If you are really lucky, someone will do your experiment — which will then not find anything."

The quest for dark matter

Though theories predict dark matter exists, we have no idea really what it looks like or what it's made of. For a while, there was "a beautiful story" that dark matter was made up of a lumbering, shy beast of a particle known as a Weakly Interacting Massive Particle, or WIMP, said co-author of the new study, John Terning, a professor of physics at the University of California, Davis. 

For years, scientists searched for these slow, chargeless particles using powerful particle accelerators. But as time went on, physicists ruled out more and more WIMP candidates— and the popular idea lost traction. Though not completely ruled out, "for the last 10 years, people have been thinking about other possibilities other than WIMPs," Terning said.

Another theory proposes that dark matter is actually made up of particles of light, or photons.

"In addition to the ordinary photons that we can see, there could be some photons that we can't see," Terning said. These so-called "dark photons" are hypothetical particles that have mass, but are lighter than electrons. Dark photons would interact — though rather weakly — with regular photons.

In this new study, Terning and his postdoctoral researcher Christopher Verhaaren built on this theory, proposing that dark matter might also be made up of dark half-magnets.These hypothetical half-magnets would be dark versions of the long-sought monopoles, or magnets that only have a single pole, that physicist Paul Dirac first proposed in the 1930s. (Despite decades of hunting, no one's found any evidence for them in nature yet.) 

Dirac didn't just propose monopoles, though; he also proposed that an electron moving around a monopole would be influenced by its magnetic field.  So, if Terning and Verhaaren's theory is right, and dark versions of these half-magnets lurk somewhere in the universe — and if those dark half-magnets act like Dirac's monopole — they would also leave subtle clues in the paths of electrons.

If  dark monopoles exist, they would emit dark photons that can transform into regular photons before being absorbed by electrons, Terning said. This interaction would cause the  electrons to rotate or change course just a tiny bit, producing an interference pattern called the Aharonov-Bohm effect. (Electrons aren't just particles, they're also waves, and an interference pattern is what shows up when the peaks and valleys in the electron's "wave equation" either add up or cancel each other out, creating a series of parallel light and dark lines.) Terning and Verhaaren propose that they might be able to detect this very slight change in electron interference patterns using electron microscopes.  

Excited by the sun

If dark matter exists, it is in us and all around us — including in and around any electron-beam microscope we would use to detect it. But to detect dark matter through its perturbation of electrons, the strange half-magnets that make up dark matter would need to have a strong-enough magnetic field. That means that these half-magnets would need to have a lot of energy.

Monopoles that pass near the sun could become excited, gain more energy and then make their way down to Earth, Terning said. He predicts that about five of these excited monopoles a day would go through something the size of their proposed electron-beam microscope. "That's not bad because usual WIMP detectors would be happy if they got five events per year," he said.

In addition, the change in electron phase caused by dark half-magnets would be so tiny that, in order to detect it, we'd need incredibly high-resolution electron-beam microscopes — the ones currently in existence probably aren't powerful enough. This electron microscope would need to have a resolution that's five times greater than those that exist currently, Terning said.

In any case, we hope to "get these people with the super-fancy electron microscopes interested in searching for this" or we "might have to build another one just to sit and wait for dark matter," Terning said.

The various competing theories of dark matter would tell us completely different stories about how the early universe formed, he said. What's more, once you figure out what dark matter is actually made of — whether it's light or heavy particles — people could conceivably create dark-matter factories, of sorts, here on Earth. "If it's very light, you don't need much energy to produce your own dark matter."

The scientists published their study to the preprint journal arXiv. It has not yet been peer-reviewed. 

• The Biggest Unsolved Mysteries in Physics
• The Mysterious Physics of 7 Everyday Things
• 8 Ways You Can See Einstein's Theory of Relativity in Real Life

Originally published on Live Science.

In 1969, a giant earthquake off the coast of Portugal kicked up a tsunami that killed over a dozen people. Some 200 years prior, an even larger earthquake hit the same area, killing around 100,000 people and destroying the city of Lisbon.

Two earthquakes in the same spot over a couple hundred years is not cause for alarm. But what puzzled seismologists about these tremors was that they began in relatively flat beds of the ocean — away from any faults or cracks in the Earth's crust where tectonic plates slip past each other, releasing energy and causing earthquakes.

So what's causing the rumbles under a seemingly quiet area? [In Photos: Ocean Hidden Beneath Earth's Crust]

One idea is that a tectonic plate is peeling into two layers — the top peeling off the bottom layer — a phenomenon that has never been observed before, a group of scientists reported in April at the European Geosciences Union General Assembly held in Vienna. This peeling may be creating a new subduction zone, or an area in which one tectonic plate is rammed beneath another, according to their abstract.

The peeling is likely driven by a water-absorbing layer in the middle of the tectonic plate, according to National Geographic. This layer might have undergone a geological process called serpentinization, in which water that seeps in through cracks causes a layer to transform into soft green minerals. Now, this transformed layer might be causing enough weakness in the plate for the bottom layer to peel away from the top layer. That peeling could lead to deep fractures that trigger a tiny subduction zone, National Geographic reported. 

This group isn't the first to propose this idea, but it's the first to provide some data on it. They tested their hypothesis with two-dimensional models, and their preliminary results showed that this type of activity is indeed possible — but is still yet to be proven. 

This research has not yet been published in a peer-reviewed journal.

• Photos: The Devastating Damage from Indonesia Earthquake and ...
• Images: Rare Footage of the Devastation of the 1906 San Francisco Earthquake
• Nepal Earthquake Photos: Odd Effects of Kathmandu Temblor

Originally published on Live Science.

What is the closest planet to Earth? The answer most people would give is Venus. But … it might actually be Mercury.

Although Venus is the planet that comes closest to Earth as it sweeps by on its orbit, Mercury stays the closest to Earth the longest, according to a commentary published Tuesday (March 12) in the magazine Physics Today.

"By some phenomenon of carelessness, ambiguity, or groupthink, science popularizers have disseminated information based on a flawed assumption about the average distance between planets," Tom Stockman, a Ph.D. student at the University of Alabama; Gabriel Monroe, a mechanical engineer at the U.S. Army's Engineer Research and Development Center; and Samuel Cordner, a mechanical engineer at NASA wrote in the commentary. [See Photos of Meteorites from Around the World]

When people calculate the distance between two planets, they usually subtract the two planets' average distances from the sun. But here's the thing: That only calculates the distance between two planets when they're closest to each other, they said. Some of the time, Venus is all the way on the opposite side of the Sun because the two planets move at different speeds.

In the commentary, the researchers devised a new mathematical technique, called the point-circle method, to measure the distances between planets. This method averages the distance between a bunch of points on each planet's orbit, thereby taking time into consideration.

When measured that way, Mercury was closest to Earth most of the time. Not only that, but Mercury was also the closest planet to Saturn, and Neptune, and all of the other planets. The researchers checked their findings by mapping out where the planets were in their orbits every 24 hours for 10,000 years.

However, not everyone agrees with this new definition of "closest" planet.

"Suppose you live in a house where the people who live next door to you spend half the year someplace, maybe you live in Wisconsin and your nearest neighbors spend seven months of the long winters in Florida," said Steven Beckwith, the director of the Space Science Laboratory and professor of astronomy at UC Berkeley, who was not part of the commentary. "During the winter, the people in the next house over would be closer to you."

But most people would still say that their closest neighbors are the ones who live immediately next door for the rest of the year, Beckwith told Live Science. "It is an interesting way of redefining 'closest,' but it is hardly profound."

• Earth Quiz: Do You Really Know Your Planet?
• 5 Mars Myths and Misconceptions
• Sun Shots: Amazing Eclipse Images

Originally published on Live Science.

Five hundred and sixty-five million years ago, Earth's magnetic field almost disappeared.

But a geological phenomenon might have saved it, a new study suggests. Earth's then-liquid core likely began to solidify around that time, which strengthened the field, the group reported yesterday (Jan. 28) in the journal Nature Geoscience. This is important because the magnetic field protects our planet and its inhabitants from harmful radiation and solar winds — streams of plasma particles thrown our way by the sun.

Scientists figured out what our planet's core was like back then by looking at crystals the size of grains of sand.

They picked up samples of plagioclase and clinopyroxene — minerals that were formed 565 million years ago — in what is now eastern Quebec, Canada. These samples contain tiny magnetic needles about 50 to 100 nanometers in size, which, in molten rock, orient themselves in the direction of the magnetic field at the time. [Shine On: Photos of Dazzling Mineral Specimens]

"Those tiny magnetic particles are ideal magnetic recorders," said co-author John Tarduno, the chair of the Earth and Environmental Sciences department and a professor at the University of Rochester in New York. "When they cool, they lock in a record of Earth's magnetic field that's maintained for billions of years."

So, by sticking the crystals in a magnetometer, the researchers were able to figure out that the particles' charge was very low. In fact, 565 million years ago, Earth's magnetic field was over 10 times weaker than what it is today — the weakest ever documented.

Further, the measurements showed that the frequency of north and south pole reversals was very high. All of this suggests that "the field was extremely unusual," Tarduno told Live Science. "We were at this critical point where the dynamo almost collapsed completely." (The geodynamo is the process that maintains and grows the magnetic field.)

But then the geodynamo got a kick start once more — from the very core of our planet.

In Earth's early years, the core was all liquid. But at some point — guesses range from between 2.5 billion years to 500 million years ago — iron began to cool and freeze into a solid layer in the middle of the planet. As the inner core solidified, lighter elements like silicon, magnesium and oxygen were kicked out into the outer, liquid layer of the core, creating a movement of fluid and heat called convection. This movement of fluid in the outer core kept charged particles moving, creating an electrical current, which in turn created a magnetic field.

This convection drives and maintains the magnetic field even today. Earth's inner core is continuing to solidify and will do so for billions of years to come.

The researchers "present intriguing paleomagnetic measurements" that suggest a weak geodynamo existed 565 million years ago, which meant that the core was fully liquid, wrote Peter Driscoll, an earth and planetary scientist at the Carnegie Institution for Science in Washington, D.C., who was not a part of the research, in a commentary that accompanied the study. If their theory holds true, "the inner core may have occurred right in the nick of time to recharge the geodynamo and save Earth's magnetic shield."

Shortly after this time, the Cambrian explosion occurred and complex animals emerged across the planet. "One can speculate — and there have been some speculations — that a weaker magnetic field may have some relationship to these evolutionary events," Tarduno said. That is because a weaker field might allow more radiation to get through, which could cause DNA damage and higher mutation rates, which in turn, might have lead to more species evolving.

But this is mere speculation, Tarduno said. When Earth's magnetic field weakens a bit during events such as magnetic reversals (where the north and south poles flip), for instance, there's no evidence that species are affected, he added.

Originally published on Live Science.

The ancient collision that formed the moon may also have brought with it all the ingredients needed for life, a new study finds.

Over 4.4 billion years ago, a Mars-size body smashed into a primitive Earth, launching our moon into permanent orbit around our planet.

But a new study finds that this event could have had a much larger impact than previously thought. The collision could also have imbued our planet with the carbon, nitrogen and sulfur needed for life to form, scientists reported today (Jan. 23) in the journal Science Advances.

Back then, Earth was a little like Mars is today. It had a core and it had a mantle, but its noncore portion was very poor in volatile elements such as nitrogen, carbon and sulfur. [Science Fact or Fantasy? 20 Imaginary Worlds]

Elements in the noncore parts of our planet, called the "bulk silicate Earth," can intermingle with each other, but they never interact with the elements of the core. Though some volatiles existed in the core, they couldn't make their way to the planet’s outer layers. And then a collision happened.

One theory holds that special kinds of meteorites, called carbonaceous chondrites, slammed into Earth and gave the bulk silicate Earth these volatile elements. This idea rests on the fact that the ratios of different versions — or isotopes — of nitrogen, carbon and hydrogen seem to match those found on these meteorites. So, proponents of the theory argue, the meteorites must be the source of these elements.

But there's just one problem: the ratio of carbon to nitrogen is off.

While the meteorites have about 20 parts carbon to one part nitrogen, Earth's noncore material has about 40 parts carbon to each part nitrogen, according to study author Damanveer Grewal, a fourth-year Ph.D. student in the Department of Earth, Environmental and Planetary Sciences at Rice University in Houston, Texas.

An ancient collision

So, the study authors' group decided to test another theory: What if another planet brought the goodies?

"Earth could have collided with many different kinds of planets," Grewal told Live Science. Could one of those planets have given the bulk silicate Earth the correct proportion of elements?

If this collision happened, the two planetary cores would have merged and the two mantles would have merged.

So, they set out to create a possible planet that could have collided with our own.

In the lab, in a special kind of furnace, Grewal and his team created the high-temperature, high-pressure conditions under which a planet’s core might form. In capsules of graphite (a form of carbon), they combined metallic powder (which represents the core and includes elements such as iron bound to nitrogen) with different proportions of silicate powder (a mixture of silicon and oxygen, meant to mimic the hypothetical planet’s mantle).

By varying the temperature, the pressure and the proportions of sulfur in their experiments, the team created scenarios of how these elements could have divided between the core and the rest of the hypothetical planet.

They found that carbon is much less willing to bond with iron in the presence of high concentrations of nitrogen and sulfur, while nitrogen bonds with iron even when a lot of sulfur is present. So for nitrogen to be excluded from the core, and be present in other parts of the planet, it should have contained very high concentrations of sulfur, Grewal said.

They then fed these possibilities into a simulation, along with information about how different volatile elements behave, and the present-day amounts of carbon, nitrogen and sulfur in Earth’s outer layers.

After running over 1 billion simulations, they found that the scenario that made the most sense — the one that had the most probable timing and could lead to a correct ratio of carbon to nitrogen — was one that posited a collision and merger of Earth with a Mars-size planet that contained about 25 to 30 percent sulfur in its core.

This theory "is very probable," said Célia Dalou, an experimental petrologist at the Centre de Recherches Pétrographiques et Géochimiques in France, who was not a part of the study. "This work is a very successful result of years of research of various different teams."

Originally published on Live Science.

Scientists are keeping their fingers crossed for numerous quakes — marsquakes, that is.

Nov. 26, NASA's newest Mars exploration mission, called the Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) mission, is scheduled to touch down on the surface of the Red Planet. With a design inspired by the older Mars lander Phoenix, this next-generation machine will extend its robot arms and place a seismometer — a device that measures quakes — onto the surface of Mars. If all goes well, for two Earth years (one Mars year), it will listen for vibrations that happen beneath the surface of the planet, to answer some fundamental questions about how rocky planets, including our own, formed. [Mars InSight Photos: A Timeline to Landing on the Red Planet]

But what are marsquakes, and why are NASA scientists hunting for them?

Marsquakes, just like earthquakes, are vibrations that move through the ground. But the way these quakes form on the Red Planet may be fundamentally different from how they form on Earth. And it turns out that these differences could help scientists better understand what early Earth looked like.

For the most part, earthquakes on our planet occur because of plate tectonics, the mechanics that occur as the plates that make up Earth's outer shell glide over the mantle, Earth's rocky innards. These tectonic plates are constantly moving — roughly between 2 and 4 inches (5 to 10 centimeters) each year, according to Britannica — bumping into and slipping past one another. Sometimes, when a plate is moving past another plate, its rough edge gets stuck and stops, while the rest of the plate continues to move. Because that part of the plate is stuck, it stores up the energy it would normally use to move, eventually catching up to the rest of the plate and releasing all the energy as seismic waves — causing shaking, according to the U.S. Geological Survey (USGS).

But Mars doesn't have a fragmented outer shell like Earth does. So how does it still have quakes? Well, it turns out, other phenomena can also cause these seismic waves, such as the stress of a slightly shrunken surface caused by planetary cooling, the pressure of magma pushing up toward the surface or even meteorite impacts, according to NASA.

But these vibrations, in comparison to Earth's, are very small.

"What we're trying to measure are vibrations so small, they're kind of on the scale of an atom," Bruce Banerdt, InSight principal investigator at NASA's Jet Propulsion Laboratory, said during a news conference on May 3.

Quakes tell us what's beneath the surface

As the seismic waves "travel through the planet, they actually pick up information along the way," Banerdt said. Different materials underground reflect seismic waves in different ways, and from those differences, scientists will be able to figure out the makeup of Mars' interior. "You can put together a 3D view of Mars," Banerdt said.

While Earth's early history has been wiped away by the constant churning and recycling of the crust, Mars still bares fingerprints of its own, according to Banerdt. "The Earth is so active that the evidence of all those processes has gotten basically erased by plate tectonics," he said.

So, looking at seismic waves inside our own planet doesn't tell us much about how it formed. Since all the rocky planets formed the same way, and then radically diverged in makeup and appearance over billions of years, looking at Mars could tell us a lot about how our own planet formed, Banerdt said.

InSight also has instrumentation to do things such as measure the temperature of Mars' interior and track the "wobble" of the north pole to reveal the makeup and size of the planet's metallic core, according to NASA.

"The science that we want to do with this mission is really a science of understanding the early solar system," Banerdt said.

Editor's note: This story was originally published May 3, 2018, two days before the scheduled launch of the Mars InSight lander from Vandenberg Air Force Base in California. The launch took place on May 5, 2018 at 4:05 a.m. PT.

Originally published on Live Science.

A mysterious white-colored plume extending some 950 miles (just over 1,500 kilometers) has been spotted on the leeward side of the Arsia Mons volcano on Mars.

Unlike other Martian cloud structures that seem to poof in and out of existence, this one has staying power, with the lengthy plume hovering near Arsia Mons since Sept. 13 and seen as recently as Nov. 12, according to the European Space Agency. The agency's Mars Express camera has been recording images of the mountainous cloud.

"Montane clouds are very common on Mars, but it was the length of the cloud and its duration that makes it interesting," said Francois Forget, a senior research scientist at the National Center for Scientific Research (CNRS) in Paris. "Usually, it is more localized to the volcano." [The 7 Most Mars-Like Places on Earth]

Forget and his colleagues could rule out volcanic spewing as the cause of the cloud: The Arsia Mons volcano has been inactive for at least 10 million years, and its peak activity occurred even longer ago — about 150 million years ago. At approximately 12 miles (20 km) high, Arsia Mons is the southernmost volcano of a group of three ancient volcanoes located on an elevated plateau known as the Tharsis region on Mars.

The development of the plume, called an orographic or lee cloud, is due to a combination of factors that are common in mountain regions on Mars and even on Earth.

Dust and cooler air are the main ingredients. The images of the plume were taken after a global dust storm had finally subsided on Mars. While dust storms occur, sometimes they develop into global storms, as happened this year.

"The dust storms create darkened conditions and reduced heat at the planet surface and increased absorption of solar radiation and heating by the dust particles high in the atmosphere," Forget said. "Just like tropical air on Earth, when this unusually warm air encounters a topographic feature such as a mountain or ancient volcano such as Arsia Mons, disturbance in the air parcel is created as it is forced upward and over the volcano to even higher elevation."

At higher elevations, the air temperatures are cooler and the atmosphere is thinner, he added.

When the air cools to its dew point, the water condenses and water-ice clouds form.

"Given the conditions, the ice particles do not sublimate [transition directly from ice to water vapor]. As a result, the cloud transports water ice a long way, constantly being renewed by the wind," Forget said. He added that"the plume on Mars is similar to the varying duration of contrails from airplanes."

These hot exhaust trails from airplanes are also rich in water vapor. If the air is cold and humid, the exhaust condenses and may freeze, similar to what happens with the warm, humid Martian air when it hits these higher topographic features.

As for why the Martian plume is so long-lasting, Forget suggested it has to do with high humidity. The more humid the air, the more likely that the lee cloud can renew itself on the waves of air for such a long distance on the leeward side of the volcano. "We can speculate that before encountering the volcano, the air was 'supersaturated' with water vapor so that once condensed the water-ice cannot sublimate," he added.

"The fact that the same formations did not replicate themselves farther north to the other volcanoes may be an indication that the northern hemisphere is just starting its winter solstice and is typically a more cloud-free period," Forget said. "The southern hemisphere, where Arsia Mons is located, is just starting its summer."

Originally published on Live Science.

Bizarre, star-like objects that act like single, giant atoms may be hidden throughout the universe, and for the first time, researchers have shown how these strange quantum stars could form.

If these objects do exist, they could help explain dark matter, the unknown stuff that emits no light and yet makes up 27 percent of the universe. They could also be behind bright, fast bursts of cosmic radio waves that have confounded astronomers and even stoked thoughts of alien civilizations.

Unlike regular stars, these so-called axion stars (if they exist) do not shine. They're dark because they're made of hypothetical particles called axions, a primary candidate for dark matter. Different theories predict axions to have a wide range of masses, but overall, they're expected to be extremely light — perhaps as tiny as 10 raised to the 31st power times lighter than a proton. [Strange Quarks and Muons, Oh, My! Nature's Tiniest Particles Dissected]

Cold, dark stars

Axions, if they do exist, would hardly interact with one another, but if gravity can coax them together, they could form a dense sphere with exotic properties unlike those of any other kind of star. That's because axions are bosons, a class of particles that includes particles of light, or photons.

In quantum physics, particles have discrete amounts of energy, meaning the particles exist at particular energy levels. With bosons, multiple particles can be at the same energy level simultaneously, unlike a different class of particle called fermions, which include electrons and protons. In an axion star — or, more generally, a boson star — every axion would be at the lowest energy level, meaning that the entire star would have the same quantum behavior, as if it were a single, giant particle.

Such an exotic object is also known as a Bose-Einstein condensate, a type of matter that physicists create in labs on Earth by cooling atoms to near absolute zero. In the lab, these condensates can also form superfluids, which flow without friction.

Previously, some physicists said that the gravity between the featherweight axions would be too weak to corral the particles into a star, said study co-author Dmitry Levkov, a physicist at the Institute for Nuclear Research of the Russian Academy of Sciences.

Star formation in no time

But new computer simulations, described on Oct. 12 in the journal Physical Review Letters, suggest that axion stars could indeed form quite readily, depending on the mass of the axion. For one relatively heavy axion, called a QCD axion, it might take 1 billion years for an axion star to form. (The QCD axion is a favorite candidate for dark matter among some physicists, because it could also solve a mystery related to the strong force, which holds atomic nuclei together.)

For an extremely light axion — about 100 quadrillion times lighter than the QCD axion and dubbed "fuzzy dark matter" — it could take just 10 million years to build an axion star, Levkov told Live Science.

"It's really interesting that just gravity can help you form Bose-Einstein condensates if given enough time — and that time is less than the age of the universe," Bhupal Dev, a physicist at Washington University in St. Louis who wasn't involved in the research, told Live Science.

Previous simulations started with smaller chunks of axion Bose-Einstein condensates, which then attracted one another via gravity to form axion stars, Levkov said. But in the new simulations, the researchers started with nothing but a gas of axions, and they found that a star formed all on its own. "We were very excited when we saw the Bose-Einstein star," Levkov said. Over time, such a star could continue to accumulate axions and grow.

"It's nice work," said Sebastian Baum, a physicist at Stockholm University in Sweden who wasn't part of the study. "It's an important stepping stone in understanding the story of such objects and, in general, axion dark matter."

If much of the dark matter is contained in these stars, Baum told Live Science, then axions could be rarer elsewhere — and thus harder to find on Earth using detectors like the Axion Dark Matter Experiment at the University of Washington in Seattle.

Axion stars could also produce detectable signals themselves. Axions can decay into photons, and a series of particle reactions from an axion star could produce detectable radiation. And if an axion star slammed into a neutron star, the collision could generate powerful blasts of radio-frequency radiation —potentially explaining the mysterious fast-radio bursts that have perplexed astronomers. Over the last few years, astronomers have detected dozens of powerful cosmic radio signals of unknown origin, prompting a plethora of explanations, including the possibility that the beams were coming from alien civilizations.

Originally published on Live Science.

Over 8 trillion gallons of rain fell on North Carolina during Hurricane Florence, according to an unofficial estimate reported by the National Weather Service in Raleigh.

As the floodwaters rose, they churned up pollution and debris, which then was fed into the swollen rivers of North Carolina, a new NASA image reveals. Snapped on Sept. 19 by NASA's Operational Land Imager on the Landsat 8 satellite, this image shows how Hurricane Florence affected water quality: the White Oak River, New River and Adams Creek spew darkened water into an equally discolored Atlantic Ocean. [Hurricane Florence: Photos of a Monster Storm]

Organic matter such as leaves, roots or bark contains pigments and chemicals that can color the water different shades, based on how much is in the water. In this image, the darker brown colors represent higher concentrations of contaminants, while the blues and greens have lower concentrations of contaminants.

The second image combines visible and infrared information to better reveal how much "colored dissolved organic matter" is present in the rivers and the Atlantic, according to the statement.

One type of contaminant, pig waste, can lead to mass fish die-offs and algal blooms, Live Science previously reported. It's not clear if pig waste is part of the contamination shown in the image.

Meanwhile, most of the rivers in North Carolina remain flooded, but water levels in some have begun receding, while some are still rising, according to NASA. Many homes, buildings and roads are still submerged in standing water.

Originally published on Live Science.

Space is filled with bizarre signals that we scramble to put meaning to — and now, researchers have detected yet another mysterious signal. This one emanated from near a neutron star, and for the first time, it's infrared.

So, what's nearby that could have created the weird signal? Scientists have a few ideas.

When a star reaches the end of its life, it typically undergoes a supernova explosion— the star collapses, and if it has enough mass, it will form a black hole. But if the star isn't massive enough, it will form a neutron star. [Supernova Photos: Great Images of Star Explosions]

Neutrons stars are very dense and, as their name suggests, are made up mostly of closely packed neutrons. Neutron stars can also be called "pulsars" if they are highly magnetized and rotate rapidly enough to emit electromagnetic waves, according to Space.com.

Typically, neutron stars emit radio waves or higher-energy waves such as X-rays, according a statement released by NASA yesterday (Sept. 17). But an international group of researchers from Penn State, the University of Arizona and Sabanci University in Turkey observed something interesting in NASA's Hubble Space Telescope data: a long signal of infrared light emitted near a neutron star, the researchers reported yesterday in The Astrophysical Journal.

This signal, they found, was about 800 light-years away and was "extended," meaning it was spread across a large stretch of space, unlike typical "point" signals from neutron stars that emit X-rays. Specifically, the signal stretched across 200 astronomical units (AU) of space, or 2.5 times the orbit of Pluto around the sun, according to a statement from Penn State. (One AU is the average distance from Earth to the sun — about 93 million miles, or 150 million kilometers.)

Such extended signals have been observed before, but never in the infrared, lead author Bettina Posselt, an associate research professor of astronomy and astrophysics at Penn State, told Live Science.

Based on previous data, the amount of infrared radiation is much more than the neutron star should be emitting, Posselt said. So "all of the emission in infrared we see is likely not coming from the neutron star itself," Posselt said. "There's something more."

The neutron star in question, RX J0806.4-4123, is one of the nearby X-ray pulsars collectively known as the Magnificent Seven. They are bizarre characters: They rotate much more slowly than typical neutron stars (it takes 11 seconds for one rotation of RX J0806.4-4123, whereas typical ones rotate in a fraction of a second), and they're much hotter than they should be based on when they formed.

In their study, the researchers proposed two possibilities for what could have snuggled up near RX J0806.4-4123 and emitted these mysterious signals: a disk of dust that surrounds the pulsar, or a "pulsar wind nebula."

A "fallback disk" — that could stretch 18 billion miles across — could have formed from the remnants of a resident star following a supernova explosion, Posselt said. Such disks that "have been long searched for, but not found" would most likely be made up mainly of dust particles, she added.

The inner part of such a disk would likely have enough energy to produce infrared light, Posselt said. This could also help explain why RX J0806.4-4123 is so hot and spins so slowly. "The disks in the past could have provided some extra heating," and also slowed down its rotation, Posselt said.

The second explanation is that perhaps the infrared signal is coming from a nearby pulsar wind nebula.

A pulsar wind can form when electrons from a neutron star are accelerated in an electric field produced by the neutron star's fast rotation and strong magnetic field, according to the NASA statement. As the neutron star moves through space, typically faster than the speed of sound, it crashes into the interstellar medium — those tiny bits of gas and dust that reside between large celestial objects. The interaction between the interstellar medium and the pulsar wind can produce the so-called pulsar wind nebula, which could give off infrared radiation, Posselt said.

Pulsar wind nebulas are typically seen emitting X-rays, so a pulsar wind nebula that radiates only in the infrared is "definitely interesting," Posselt said.

Originally published on Live Science.

Every day, the Earth spins once around its axis, making sunrises and sunsets a daily feature of life on the planet. It has done so since it formed 4.6 billion years ago, and it will continue to do so until the world ends — likely when the sun swells into a red giant star and swallows the planet. But why does it rotate at all?

The Earth formed out of a disk of gas and dust that swirled around the newborn sun. In this spinning disk, bits of dust and rock stuck together to form the Earth, according to Space.com, a sister site of Live Science. As it grew, space rocks continued colliding with the nascent planet, exerting forces that sent it spinning, explained Smadar Naoz, an astrophysicist at the University of California, Los Angeles. Because all the debris in the early solar system was rotating around the sun in roughly the same direction, the collisions also spun the Earth — and most everything else in the solar system — in that direction. [Photo Timeline How the Earth Formed]

But why was the solar system spinning in the first place? The sun, and the solar system, formed when a cloud of dust and gas collapsed due to its own weight. Most of the gas condensed to become the sun, while the remaining material went into the surrounding, planet-forming disk. Before it collapsed, the gas molecules and dust particles were moving all over the place, but at a certain point, some gas and dust happened to shift a bit more in one particular direction, setting its spin in motion. When the gas cloud then collapsed, the cloud's rotation sped up — just as figure skaters spin faster when they tuck their arms and legs in.

Because there isn't much in space to slow things down, once something starts rotating, it usually keeps going. The rotating baby solar system in this case had lots of what's called angular momentum, a quantity that describes the object's tendency to keep spinning. As a result, all the planets likely spun in the same direction when the solar system formed.

Today, however, some planets have put their own spin on their motion. Venus rotates in the opposite direction as Earth, and Uranus' spin axis is inclined 90 degrees. Scientists aren't sure how these planets got this way, but they have some ideas. For Venus, maybe a collision caused its rotation to flip. Or maybe it began rotating just like the other planets. Over time, the sun's gravitational tug on Venus' thick clouds, combined with friction between the planet's core and mantle, caused the spin to flip. A 2001 study published in Nature suggested that gravitational interactions with the sun and other factors might have caused Venus' spin to slow down and reverse.

In the case of Uranus, scientists have suggested that collisions — one huge crash with a big rock or maybe a one-two punchwith two different objects — knocked it off kilter, Scientific American reported.

Despite these kinds of disturbances, everything in space rotates in one direction or another. "Rotating is a fundamental behavior of objects in the universe," Naoz said.

Asteroids rotate. Stars rotate. Galaxies rotate (it takes 230 million years for the solar system to complete one circuit around the Milky Way, according to NASA). Some of the fastest things in the universe are dense, whirling objects called pulsars, which are the corpses of massive stars. Some pulsars, which have a diameter about the size of a city, can spin hundreds of times per second. The fastest one, announced in Science in 2006 and dubbed Terzan 5ad, rotates 716 times per second.

Black holes can be even faster. One, called GRS 1915+105, may be spinning anywhere between 920 and 1,150 times per second, a 2006 study in the Astrophysical Journal found.

But things slow down, too. When the sun formed, it spun once around its axis every four days, Naoz said. But today, it takes about 25 days for the sun to spin once, she said. Its magnetic field interacts with the solar wind to slow its rotation, Naoz said.

Even Earth's rotation decelerates. Gravity from the moon pulls on Earth in a way that ever so slightly slows it down. A 2016 analysis in the journal Proceedings of the Royal Society A of ancient eclipses showed that Earth's rotation slowed by about 6 hours over the last 2,740 years. That comes out to just 1.78 milliseconds over a century.

So, while the sun will rise tomorrow, it just may be a tad late.

Originally published on Live Science.

It's the year 2300. Extreme weather events such as building-flattening hurricanes, years-long droughts and wildfires are so common that they no longer make headlines. The last groups of humans left near the sizzling equator pack their bags and move toward the now densely populated poles.

This so-called "hothouse Earth," where global temperatures will be 7 to 9 degrees Fahrenheit (4 to 5 degrees Celsius) higher than preindustrial temperatures and sea levels will be 33 to 200 feet (10 to 60 meters) higher than today, is hard to imagine — but easy to fall into, said a new perspective article published today (Aug. 6) in the journal Proceedings of the National Academy of Sciences. [Top 9 Ways the World Could End]

In the article, a group of scientists argued that there is a threshold temperature above which natural feedback systems that currently keep the Earth cool will unravel. At that point, a cascade of climate events will thrust the planet into a "hothouse" state. Though the scientists don't know exactly what this threshold is, they said it could be as slight as 2 degrees C (around 4 degrees F) of warming above preindustrial levels.

Sound familiar? The 2 degrees C mark plays a big role in the Paris Agreement, the landmark 2016 agreement signed by 179 countries to combat climate change by reducing carbon emissions (the same one that the U.S. announced it would withdraw from last year). In that accord, countries agreed to work to keep global temperature rise well below 2 degrees C, and ideally below 1.5 degrees C, above preindustrial levels this century.

"This paper gives very strong scientific support … that we should avoid coming too close or even reaching 2 degrees Celsius warming," article co-author Johan Rockström, director of the Stockholm Resilience Center and a professor of water systems and global sustainability at Stockholm University in Sweden, told Live Science.

Changing Earth's rhythm

For the last million years, Earth has naturally cycled in and out of an ice age every 100,000 years or so. The planet left the last ice age around 12,000 years ago and is currently in an interglacial cycle called the Holocene epoch. In this cycle, Earth has natural systems that help keep it cool, even during the warmer interglacial periods.

But many scientists argue that due to the immense impact of humans on climate and the environment, the current geological age should be called the Anthropocene (from anthropogenic, which means originating with human activity). Temperatures are almost as hot as the maximum historical temperature  during an interglacial cycle, Rockström said.

If carbon emissions continue unabated, the planet might leave the glacial-interglacial cycle and be thrust into a new age of the "hothouse Earth."

Today, we emit 40 billion tons of carbon dioxide a year from burning fossil fuels, Rockström said. But roughly half of those emissions are taken up and stored by the oceans, trees and soil, he said.

However, we are now seeing signs that we are pushing the system too far — cutting down too many trees, degrading too much soil, taking out too much fresh water and pumping too much carbon dioxide into the atmosphere, Rockström said.

Scientists fear that if we reach a certain temperature threshold, some of these natural processes will reverse and the planet "will become a self-heater,"Rockström said. That means, forests, soil and water will release the carbon they're storing.

"The moment the planet becomes a source of greenhouse gas emissions together with us humans, then as you can imagine, things are accelerating very fast in the wrong direction," he said. [Doom and Gloom: Top 10 Postapocalyptic Worlds]

Many tipping points

In their perspective paper, Rockström and his team corroborated existing literature on various natural feedback processes and concluded that many of them can serve as "tipping elements." When one tips, many of the others follow.

Nature has feedback mechanisms, such as a rainforest's capability to create its own humidity and rain, that keep ecosystems in equilibrium. If the rainforest is subject to increasing warming and deforestation, however, the mechanism slowly gets weaker, Rockström said.

"When it crosses a tipping point, the feedback mechanism changes direction," Rockström said, and the rainforest morphs from a moisture engine into a self-dryer. Eventually, the rainforest turns into a savanna and, in the process, releases carbon, he said.

This, in turn, can become part of a cascade that would influence other processes around the world, such as ocean circulation and El Niño events. Other tipping points include the thawing of permafrost, loss of Arctic summer sea ice and the loss of coral reefs.

A global call for help

The first big goal should be to completely stop carbon emissions by 2050, Rockström said. But that won't be enough, he added.

In order to stay away from these tipping points, the "whole world [needs to] embark on a major project to become sustainable across all sectors," he said.

That could be a challenge, as countries around the world grow increasingly nationalistic, he said. Instead of focusing on narrow national goals, the world should collectively work to reduce carbon emissions — for instance by creating investment funds that can support poorer nations that don't have as much capacity to reduce emissions as richer countries do, he said.

All of this means "that it's, scientifically speaking, completely unacceptable that a country like the U.S. leaves the Paris Agreement, because now more than ever, we need every country in the world to collectively decarbonize … in order to secure a stable planet," Rockström said.

The new paper is an opinion article that includes no new research but rather draws on the existing literature, Michael Mann, a distinguished professor of meteorology at Pennsylvania State University who was not part of the study, told Live Science in an email.

"That having been said, the authors do, in my view, make a credible case that we could, in the absence of aggressive near-term efforts to reduce carbon emissions, commit to truly dangerous and irreversible climate change in a matter of decades," Mann said.

Originally published on Live Science.

This article was originally published at The Conversation. The publication contributed the article to Live Science's Expert Voices: Op-Ed & Insights.

Speakers recently flew in from around (or perhaps, across?) the earth for a three-day event held in Birmingham: the UK's first ever public Flat Earth Convention. It was well attended, and wasn't just three days of speeches and YouTube clips (though, granted, there was a lot of this). There was also a lot of team-building, networking, debating, workshops – and scientific experiments.

Yes, flat earthers do seem to place a lot of emphasis and priority on scientific methods and, in particular, on observable facts. The weekend in no small part revolved around discussing and debating science, with lots of time spent running, planning, and reporting on the latest set of flat earth experiments and models. Indeed, as one presenter noted early on, flat earthers try to "look for multiple, verifiable evidence" and advised attendees to "always do your own research and accept you might be wrong".

While flat earthers seem to trust and support scientific methods, what they don't trust is scientists, and the established relationships between "power" and "knowledge". This relationship between power and knowledge has long been theorised by sociologists. By exploring this relationship, we can begin to understand why there is a swelling resurgence of flat earthers.

Read more: How to reason with flat earthers (it may not help though)

Power and knowledge

Let me begin by stating quickly that I'm not really interested in discussing if the earth if flat or not (for the record, I'm happily a "globe earther") – and I'm not seeking to mock or denigrate this community. What's important here is not necessarily whether they believe the earth is flat or not, but instead what their resurgence and public conventions tell us about science and knowledge in the 21st century.

Multiple competing models were suggested throughout the weekend, including "classic" flat earth, domes, ice walls, diamonds, puddles with multiple worlds inside, and even the earth as the inside of a giant cosmic egg. The level of discussion however often did not revolve around the models on offer, but on broader issues of attitudes towards existing structures of knowledge, and the institutions that supported and presented these models.

Flat earthers are not the first group to be skeptical of existing power structures and their tight grasps on knowledge. This viewpoint is somewhat typified by the work of Michel Foucault, a famous and heavily influential 20th century philosopher who made a career of studying those on the fringes of society to understand what they could tell us about everyday life.

He is well known, amongst many other things, for looking at the close relationship between power and knowledge. He suggested that knowledge is created and used in a way that reinforces the claims to legitimacy of those in power. At the same time, those in power control what is considered to be correct and incorrect knowledge. According to Foucault, there is therefore an intimate and interlinked relationship between power and knowledge.

At the time Foucault was writing on the topic, the control of power and knowledge had moved away from religious institutions, who previously held a very singular hold over knowledge and morality, and was instead beginning to move towards a network of scientific institutions, media monopolies, legal courts, and bureaucratized governments. Foucault argued that these institutions work to maintain their claims to legitimacy by controlling knowledge.

Ahead of the curve?

In the 21st century, we are witnessing another important shift in both power and knowledge due to factors that include the increased public platforms afforded by social media. Knowledge is no longer centrally controlled and – as has been pointed out in the wake of Brexit – the age of the expert may be passing. Now, everybody has the power to create and share content. When Michael Gove, a leading proponent of Brexit, proclaimed: "I think the people of this country have had enough of experts," it would seem that he, in many ways, meant it.

It is also clear that we're seeing increased polarization in society, as we continue to drift away from agreed singular narratives and move into camps around shared interests. Recent PEW research suggests, for example, that 80% of voters who backed Hillary Clinton in the 2016 US presidential election – and 81percent of Trump voters – believe the two sides are unable to agree on basic facts.

Despite early claims, from as far back as HG Wells' "world brain" essays in 1936, that a worldwide shared resource of knowledge such as the internet would create peace, harmony and a common interpretation of reality, it appears that quite the opposite has happened. With the increased voice afforded by social media, knowledge has been increasingly decentralized, and competing narratives have emerged.

This was something of a reoccurring theme throughout the weekend, and was especially apparent when four flat earthers debated three physics PhD students. A particular point of contention occurred when one of the physicists pleaded with the audience to avoid trusting YouTube and bloggers. The audience and the panel of flat earthers took exception to this, noting that "now we've got the internet and mass communication … we're not reliant on what the mainstream are telling us in newspapers, we can decide for ourselves". It was readily apparent that the flat earthers were keen to separate knowledge from scientific institutions.

Flat earthers and populism

At the same time as scientific claims to knowledge and power are being undermined, some power structures are decoupling themselves from scientific knowledge, moving towards a kind of populist politics that are increasingly skeptical of knowledge. This has, in recent years, manifested itself in extreme ways – through such things as public politicians showing support for Pizzagate or Trump's suggestions that Ted Cruz's father shot JFK.

But this can also be seen in more subtle and insidious form in the way in which Brexit, for example, was campaigned for in terms of gut feelings and emotions rather than expert statistics and predictions. Science is increasingly facing problems with its ability to communicate ideas publicly, a problem that politicians, and flat earthers, are able to circumvent with moves towards populism.

Again, this theme occurred throughout the weekend. Flat earthers were encouraged to trust "poetry, freedom, passion, vividness, creativity, and yearning" over the more clinical regurgitation of established theories and facts. Attendees were told that "hope changes everything", and warned against blindly trusting what they were told. This is a narrative echoed by some of the celebrities who have used their power to back flat earth beliefs, such as the musician B.O.B, who tweeted: "Don't believe what I say, research what I say."

In many ways, a public meeting of flat earthers is a product and sign of our time; a reflection of our increasing distrust in scientific institutions, and the moves by power-holding institutions towards populism and emotions. In much the same way that Foucault reflected on what social outcasts could reveal about our social systems, there is a lot flat earthers can reveal to us about the current changing relationship between power and knowledge. And judging by the success of this UK event – and the large conventions planned in Canada and America this year – it seems the flat earth is going to be around for a while yet.

Harry T Dyer, Lecturer in Education, University of East Anglia

This article was originally published on The Conversation. Read the original article. Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook, Twitter and Google +. The views expressed are those of the author and do not necessarily reflect the views of the publisher. This version of the article was originally published on Live Science.

Roughly 13.8 billion years ago, the Universe as we know it expanded from an infinitely hot and dense singularity in space and time, first in a furious torrent of rapid cosmic inflation for a fraction of a second, and then in the more calm manner we see today – gradual, yet accelerating expansion fueled by dark energy.

This fleetingly describes the Big Bang model of cosmology, the most successful theoretical explanation for our grand Universe. Backed by boatloads of observational evidence, we can be very sure of its veracity. Caltech astrophysicist Sean Caroll even described the Big Bang as "100 percent true."

But that percentage of surety dwindles to nothing when discussing the singularity that supposedly started it all. Where did it come from? What came before it? What caused it to "bang" in such a big way? As Carroll admitted, this singularity and its accompanying "bang" are essentially stand-ins for what we don't – and currently can't – actually know.

"It's the time at which we don’t understand what the Universe was doing," he said on Science Friday.

And we might not ever understand it, at least with current methods of observation.

"The exponential nature of inflation wipes out any information that occurred prior to that, separating it from anything we can observe by, well, inflating it beyond the portion of our Universe that we can observe," astrophysicist Ethan Siegel wrote.

We're at a dead end, it seems.

"It certainly looks like the universe that we observe around us… definitely had a beginning," MIT cosmologist Alan Guth, the originator of the theory of cosmic inflation, said in an interview for the PBS show Closer to Truth. "That doesn't mean that that beginning was necessarily the ultimate beginning of all of reality. There may have been some prehistory to what we're here calling the beginning."

Fanciful ideas abound to account for that prehistory. Eternal inflation suggests that our universe is but a mere bubble in what physicist Matt Francis described as a "larger froth of inflation" of an even grander universe. Cyclic inflation proffers that our observable universe is the region in between two membranes of parallel shadow universes. Another theory proposes that our universe emerged from the singularity of a black hole and we are contained within the event horizon.

All of these ideas sound cool, but none are reasonably testable, rendering them useless at the present time. They share this state of futility with the Big Bang's theorized singularity and all other explanations for how everything really began. Ethan Siegel explained why, and what this means:

We will likely never know for sure how everything began, or even if there was a beginning. Perhaps the timeless quest to uncover our ultimate origins is pointless, a selfish side effect of our innate human need for a coherent narrative of existence. Indeed, the very concept of a beginning may be flawed, based on our comparatively paltry experience in this mystical reality. The Universe, and indeed all of Reality, is by no means required to conform to our concept of a "beginning".

And of course, no matter how far down the rabbit hole we travel, there could always be a question of "what came before?" The search for a beginning will likely never end.

Originally published on RealClearScience.

Today is the day.

It's the beginning of the end, according to practiced doomsday diviner David Meade. On April 23, 2018, Meade says, the sun, the moon and Jupiter will line up in the constellation Virgo (in actuality, they will not be in that constellation) — an alignment that has biblical disaster written all over it.

In the Bible, Revelation 12:1-2 speaks of a "woman clothed with the sun, with the moon under her feet and a crown of twelve stars on her head," who labors to give birth to a dictator who will ultimately bring about the world's end.

Meade did a lot of numerical and cosmic gymnastics to come up with today's apocalypse — one that, of course, will not come to be. 

The same passage used for today's prediction was also the basis for Meade's end-of-the-world prediction last year, when he said the sky would essentially fall on Sept. 23. It did not. [End of the World? Top 10 Doomsday Threats]

And, in fact, his current forecast seems to have long roots: Baptist preacher William Miller made multiple failed doomsday predictions, and one of them was for April 23, 1843.

Sadly, perhaps for Meade, the planet Jupiter will appear not in Virgo but in the constellation Libra from Earth's perspective; the sun will appear to align with Aries, while the moon will lurk in the constellation Gemini today, according to The Sky Live.

This celestial alignment is, according to Meade, just the beginning of the cosmic catastrophe. From there, a rogue planet called Planet X will supposedly pass by Earth in October and cause a planetwide mess (worldwide volcanic eruptions) that will culminate in the return of Jesus Christ — also based on the Book of Revelation.

There are a few problems with this part of the prediction. For one, Planet X, also called Nibiru, is fictional. And whereas scientists are looking for an Earth-size planet that they sometimes refer to as "Planet X" or "Planet Nine," this is a different world altogether from the one described by Meade and others.

Nibiru, in fact, is the baby of conspiracy theorist Nancy Lieder, who floated the idea in the 1990s. This rogue planet — a body that astronomers who stare at the skies, looking for actual alien worlds, would not miss — was the basis for the failed 2012 Maya apocalypse, among others.   

Besides Nibiru being a made-up world that has been debunked repeatedly, the Revelation passage also has some issues.

"The author of Revelation was wrong in his predictions, so neither this book nor any other ancient book is of much relevance for predicting the future," Allen Kerkeslager, a professor of ancient and comparative religion at St. Joseph's University in Philadelphia, told Live Science earlier this month.

All this is to say, the doomsday prediction is bogus. Happy Monday.

Original article on Live Science.

Astronomer Peter Dunsby just made a groundbreaking discovery, after noticing a very bright "star" pop up in his field of view at an observatory at the University of Cape Town that was not present two weeks prior.

Too bad Dunsby was perhaps thousands of years late … the bright object was the planet Mars. Though no one knows for sure who discovered the Red Planet, Galileo Galilei observed the giant red orb — whose diameter spans a whopping 4,222 miles (6,794 km) — in 1609; and Martian fascination has arguably not waned since.

Before realizing his marvelous mistake, Dunsby posted a note on the Astronomer's Telegram, a publication for very short (under 4,000 characters) reports by astronomers, detailing his observations, in which he described the bright object had shown up between the Lagoon and Trifid nebulas, both nestled in the constellation Sagittarius.

About 40 minutres later, the Telegram issued a correction: "The object reported in ATel 11448 has been identified as Mars. Our sincere apologies for the earlier report and the inconvenience caused."

And, not to let Dunsby go quietly into the night, the Telegram also sent out a cheeky tweet: "For Discovery of Mars.  Congratulations, Prof.  Peter Dunsby!"

As for why Mars showed up in Dunsby's field of view, the blood-red planet, like Earth, makes a trek around the sun — though in a different orbit from our own.

Here's the full telegram that Dunsby published March 20:

"Peter Dunsby (University of Cape Town) reports the detection of a very bright optical transient in the region between the Lagoon and Trifid Nebulae based on observations obtained from Cape Town on 20 March 2018, between 01:00 and 03:45 UT. The object was visible throughout the full duration of the observations and not seen when this field was observed previously (08 March 2018). The optical transients is at least first magnitude and is located at the following coordinates: RA (2000): 18h 04m 50s Declination (2000.0): -23d 29m 58s The coordinates are accurate to a few arcseconds. There is no obvious counterpart at this position on the Digital Sky Survey plates. Observations were obtained using an 80mm refractor. The attached URL show the image of this field (2.3 x 1.7 degrees, plate scale of 9 arcseconds per pixel) on 20 March 2018. The optical transient is the brightest star in the field. Further observations are strongly encouraged to establish the nature of this very bright optical transient. "

Dunsby's mishap drew plenty of good-natured responses on Twitter:

Read more about Mars on our sister site Space.com.

Original article on Live Science.

Earth's magnetic poles, whatever they're doing, are not going to spark chaos and kill us all — a scenario making the rounds online right now.

According to the Australian news site news.com.au, a magnetic flip would not only cause massive blackouts, "even flushing the toilet could become impossible."

As reported by Undark, Daniel Baker, the director of the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder, is suggesting a reversal would render parts of the planet uninhabitable (though Baker is not directly quoted saying this).

Here's what's really happening and why there's no need to take cover in a doomsday bunker. [Doomsday: 9 Real Ways Earth Could End]

Oceans of molten iron are swirling deep inside the planet around the outer core. That sloshing sets up a giant bar magnet through Earth — though not a real concrete magnet, of course. This giant magnet sits at an angle of about 11 degrees from the axis around which Earth spins, according to Windows of the Universe. These poles are not in the same place as our geographic North and South poles.

And remember that swirling iron? It's constantly moving around. The result? Blobs of that iron get flipped in the opposite direction from iron atoms around them; scientists say they become "reverse-aligned." When there are enough reverse-aligned iron atoms, that giant bar magnet flips, and magnetic north becomes magnetic south.

But this bar magnet is no Olympic gymnast: The flipping isn't a quick turn but rather a gradual one, and can take between 1,000 and 10,000 years. "It's not a sudden flip, but a slow process, during which the field strength becomes weak, very probably the field becomes more complex and might show more than two poles for a while, and then builds up in strength and [aligns] in the opposite direction," Monika Korte, the scientific director of the Niemegk Geomagnetic Observatory at GFZ Potsdam in Germany, previously told Live Science.

Magnetic north and south poles have swapped places hundreds of times in Earth's history, about every several hundred thousand years or so, scientists have found. The last one happened about 780,000 years ago. [7 Ways the Earth Changes in the Blink of an Eye]

In fact, there are signs of reversal right now. The magnetic field has been weakening at a faster clip, about 10 times faster than in the past, according to data from magnetometers on board the Swarm satellites (three satellites moving in tandem). This may or may not suggest the movement of the magnetic poles, scientists said.

"What currently has geophysicists like us abuzz is the realization that the strength of Earth's magnetic field has been decreasing for the last 160 years at an alarming rate," John Tarduno and Vincent Hare, of the University of Rochester, wrote in a The Conversation article last year.

"This collapse is centered in a huge expanse of the Southern Hemisphere, extending from Zimbabwe to Chile, known as the South Atlantic Anomaly. The magnetic field strength is so weak there that it's a hazard for satellites that orbit above the region — the field no longer protects them from radiation which interferes with satellite electronics."

If the poles really did do a switcheroo, Earthlings would notice, though scientists aren't worried about a planetwide doomsday.

Just before a reversal, the extreme weakening of our magnetic field, the shield that protects us from charged particles constantly blasting the atmosphere, could cause trouble. Live Science previously reported these charged solar particles could punch holes in Earth's atmosphere akin to the ozone hole above Antarctica. Whether those holes would have any true impact is debatable, scientists have said.

The increased radiation, however, could mess with the navigation of satellites and aircraft as well as electrical power grids. "Were this to happen today, the increase in charged particles reaching the Earth would result in increased risks for satellites, aviation and ground-based electrical infrastructure," University of Leeds geophysicists Phil Livermore and Jon Mound wrote in an article for The Conversation.

And those alleged links between magnetic pole reversals and lights out for Earth and all its creatures … well, those are more fantasy than in real life.

Original article on Live Science.

New research is shedding light on the potential consequences of geoengineering the planet.

Among the most prominent technological proposals for cooling Earth's atmosphere involves spraying aerosols into the sky to reflect some of the sun's incoming radiation back into outer space. That approach, in a sense, has already been tested in nature. Big volcanic eruptions have cooled the planet by injecting ash into the atmosphere. The Mount Pinatubo eruption in 1991, for example, cooled the planet by 1 degree Fahrenheit for 15 months. 

A new study based on advanced computer modeling and published in the journal Nature Communications finds that spraying aerosols above the Northern Hemisphere would decrease the severity of Atlantic Ocean hurricanes, but spraying them in the Southern Hemisphere would have the opposite effect on the North Atlantic.

Reducing hurricane activity in the Atlantic might sound like a positive, knock-on benefit. But it comes with other likely consequences.

"That sounds beneficial after the hurricane season we've just had," Anthony Jones of the University of Exeter, one of the paper's authors, told Seeker. "But if you just inject into the north, you also increase the risk of drought in the Sahel."

RELATED: A Geoengineering 'Cocktail' Could Dull the Pain of Climate Change

The Sahel is a region in Africa bordering the Sahara Desert and is prone to acute drought. The United Nations said in 2012 that 15 million people were malnourished in West Africa and the Sahel primarily due to drought.

Jones said the risks of geoengineering — much like the damage of climate change — aren't evenly distributed around the earth.

"Geoengineering regionally and unilaterally could have dire consequences for other parts of the planet," Jones said.

Despite the risks, scientists who study geoengineering suggest the process may buy crucial time for humanity to transition away from carbon-intensive economies that are the cause of global warming.

Some of those who study geoengineering compare the idea to a painkiller that may be beneficial in the short term, but not a good long-term solution. For a patient with a life-threatening illness, a painkiller might ease the suffering, but it won't cure the disease.

A group of researchers at Harvard has been gearing up in recent months to carry out the world's first field studies of geoengineering.

"The idea that you could even think about adjusting the temperature of the planet is terrifying," Frank Keutsch, one of the Harvard scientists, told Seeker earlier this year. "But the consequences of climate change are also quite terrifying. This is a very serious subject."

Originally published on Seeker.

Four billion years ago, Earth was covered in a watery sludge swarming with primordial molecules, gases, and minerals — nothing that biologists would recognize as alive. Then somehow, out of that prebiotic stew emerged the first critical building blocks — proteins, sugars, amino acids, cell walls — that would combine over the next billion years to form the first specks of life on the planet.

A subset of chemists have devoted their careers to puzzling out the early chemical and environmental conditions that gave rise to the origins of life. With scant clues from the geological record, they synthesize simple molecules that may have existed billions of years ago and test if these ancient enzymes had the skills to turn prebiotic raw material into the stuff of life.

A team of such chemists from the Scripps Research Institute reported Nov. 6 in the journal Nature Chemistry that they identified a single, primitive enzyme that could have reacted with early Earth catalysts to produce some of the key precursors to life: the short chains of amino acids that power cells, the lipids that form cell walls, and the strands of nucleotides that store genetic information.

Ramanarayanan Krishnamurthy is an associate professor of chemistry at Scripps and lead author of the origins of life paper. For a number of years, his lab has been experimenting with a synthetic enzyme called diamidophosphate (DAP) that’s been shown to drive a critical chemical process called phosphorylation. Without phosphorylation — which is simply the process of adding a phosphate molecule to another molecule — life wouldn't exist.

"If you look at life today, and how it probably was at least three billion years ago, it was based on a lot of phosphorylation chemistry," Krishnamurthy told Seeker. "Your RNA, DNA, and a lot of your biomolecules are phosphorylated. So are sugars, amino acids, and proteins."

The enzymes that trigger phosphorylation are called kinases. They use phosphorylation to send signals instructing cells to divide, to make more of one protein than another, to tell DNA strands to separate, or RNA to form. DAP may have been one of the first primordial kinases to get the phosphorylation ball rolling, Krishnamurthy believed.  

To test his theory, Krishnamurthy and his colleagues simulated early Earth conditions in the lab, using both a water base and a muddy paste set to varying pH levels. They combined DAP with different concentrations of magnesium, zinc, and a compound called imidazole that acted as a catalyst to speed the reactions, which still took weeks or sometimes months to complete.

For DAP to pass the test, it had to successfully trigger phosphorylation events that resulted in simple nucleotides, peptides, and cell wall structures under similar conditions. Past candidates for origin-of-life enzymes could only phosphorylate certain structures under wildly different chemical and environmental conditions. DAP, Krishnamurthy found, could do it all, phosphorylating the four nucleoside building blocks of RNA, then short RNA-like strands, then fatty acids, lipids, and peptide chains.

Does that mean that DAP is the pixie dust that transformed random matter into life? Not quite, said Krishnamurthy.  

"The best we can do is try to demonstrate that simple chemicals under the right conditions could give rise to further chemistry which may lead to life-like behavior. We can't make a claim that this is the way that life formed on the early Earth."

RELATED: Life on Earth May Have Started With a Cosmic Splash

For one thing, Krishnamurthy has no proof that DAP even existed four billion years ago. He synthesized the molecule in his lab as a way to solve one of the fundamental challenges to phosphorylating in wet, early Earth conditions. For most phosphorylation reactions to work, they need to remove a molecule of water in the process.

"How do you remove water from a molecule when you are surrounded by a pool of water?" asked Krishnamurthy. "That's thermodynamically an uphill task."

DAP gets around that problem by removing a molecule of ammonia instead of water.

Krishnamurthy is working with geochemists to identify potential sources of DAP in the distant geological past. Phosphate-rich lava flows may have reacted with ammonia in the air to create DAP, or it could have been leached out of phosphate-containing minerals. Or maybe it even arrived on the back of a meteorite forged by a far-off star.

One thing is clear, without DAP or something like it, Earth might still be a lifeless mud puddle.

Originally published on Seeker.

A new study bolsters the theory that the chemical origins of life on Earth were midwifed by meteorites that delivered essential building blocks from space.

Meteorites slamming into warm, small ponds on the planet's rising land surfaces more than 4 billion years ago could have delivered those building blocks into an environment where they could grow and combine into ribonucleic acid, or RNA, said Ben K.D. Pearce, an astrobiologist at Canada's McMaster University.

The study, produced by researchers at McMaster and Germany's Max Planck Institute for Astronomy and published in the journal Proceedings of the National Academy of Sciences, is the latest in a debate over the origins of life. Did it come from Earth itself — forming around hot undersea vents in the crust — or from small ponds on land, as Darwin theorized, with material deposited from the cosmos around it? Pearce and his colleagues come down on the "warm little pond" side, arguing that the oceans were too harsh an environment for the building blocks of life.

RNA can reproduce itself and evolve. In its current form, it takes the genetic code contained in DNA and forms proteins.

"At one time, it was the dominant life form on Earth, and likely the first life form on Earth," Pearce told Seeker. But it's made up of a family of molecules known as nucleobases, which stem from a reactive type of nitrogen that wouldn't have formed on a lifeless early Earth.

RELATED: Climate Change 5 Million Years Ago Coincided With More Mediterranean Volcanoes

Nitrogen compounds like ammonia and hydrogen cyanide likely collected on bits of dust and rock floating around the sun, snowballing into larger bodies where they could react to produce nucleobases.

"You have get these molecules from space," he said. And when those space rocks fell to Earth, the nucleobases they held could have landed in ponds of water and reacted with other chemicals that produced RNA.

Previous studies have put forth that theory, but what Pearce and his colleagues have done is to use computer models to gauge how probable that would have been. Nucleotides would have to survive in an environment bombarded with ultraviolet light, since there was no protective ozone layer at the time, and in water that could have broken them up.

While other scientists, including the famous astronomer Carl Sagan, have theorized that cosmic dust may have delivered those precursors, Pearce said any nucleotides riding in on dust particles were likely to have been too small to survive in their new home.

RELATED:Mass Extinctions on Earth Coincided With Out-of-Whack Carbon Cycles

But by entering data "from all facets of science," including biology, geophysics, and astrophysics, they've calculated that meteorites would have been a frequent and durable enough vehicle to deliver the building blocks of life, and wet and dry cycles could have helped them bond into larger chains that formed RNA.

"There were thousands of opportunities for this to emerge from thousands of different pond environments," Pearce said.

Pearce said the next step will be to try to test that theory in a laboratory. Researchers at McMaster, located at the western end of Lake Ontario, are building a "planet simulator" in which they hope to reproduce the conditions of a primeval Earth and see whether they can get the same results.

Original article on Seeker.

Wow! Saturn

Since 2004, the Cassini spacecraft has been orbiting Saturn, collecting gobs of data and images, resulting in major discoveries — from geysers and hydrothermal activity on Saturn's moon Enceladus to the dynamics of the planet's rings — plus some glorious artwork. Since all the data has been made available to the public, some enthusiasts have created their own images. NASA has called these "amateur images," but you'll likely be wowed beyond belief.

3 little moons

Ian Regan created this image from a sequence captured by Cassini over 90-plus minutes on the morning of Oct. 28, 2016, Regan said. Three of Saturn's moons are visible in the image: Epimetheus, Atlas and Prometheus. The moon Epimetheus can be seen near Saturn, just above the right ansa, or the portion of the ring that appears farthest away from the planet's disk in the image. Meanwhile, Atlas and Prometheus can be seen at the tip of the left ansa. Regan noted that Pan (a moon in the A ring) is too faint to be detectable; Janus, the potato-shaped moon in the gap between the F and G rings, must be just out of frame, he added.

Moons float in midair

One of Elisabetta Bonora's favorite pastimes seems to be exploring the raw images snapped from the Cassini spacecraft and creating something amazing from them. "It's wonderful to be able to take advantage of Cassini's eyes," Bonora said in a NASA statement. "I like to dream I am there too." Bonora, a video and web analyst who lives near Savona, Italy, said this particular image jumped out at her: "From the get go, I thought this image was a splendid example of great composition and beautiful geometry."

The image shows Saturn on the left, with very thin rings that appear almost perpendicular to the field of view, she noted. "On top of the rings, right in the middle of the image, there are two moons (Rhea and Mimas) suspended in midair. It's simply a picture-perfect scene," she said.

Orbs at the edge of Saturn rings

Senior editor of The Planetary Society, Emily Lakdawalla captured this gorgeous snapshot revealing five Saturnian moons. "Cassini caught five moons at the edge of Saturn's ring system in this natural color photo from July 29, 2011." The moons, starting at the left of the image: Janus, Pandora, Enceladus, Mimas and Rhea.

Titan moon

Jason Major created this RGB-composite showing Saturn's largest moon Titan. Major used raw Cassini images acquired on Jan. 2, 2014. "The moon's south polar vortex can be seen just along the terminator, as well as its cyan-colored upper-level haze layer," Major said in a NASA statement.

Titan and Rhea

Adam Hurcewicz created this image of Titan and Rhea from a raw Cassini image taken on Dec. 10, 2011. Though Saturn's second-largest moon, Rhea is still dwarfed by Titan; The highly cratered Rhea has an average radius of 475 miles (764 km), or less than a third that of Titan, according to NASA.

Saturn in blue

"This is our first attempt at playing with one of the raw images. We wanted to get our 13-year-old excited about space exploration," image producer Earnest Hamby said in a NASA statement."The image was created with iPhoto on our iPad and only took a few minutes. We're true amateurs who appreciate everything the Cassini team is doing. Keep up the good work."

Color me purple

Gloria Roberts created this image of Saturn from a raw image taken by Cassini on March 20, 2014. Roberts used Adobe Photoshop Elements to colorize the resulting image to create the purple hue. On March 24, 2014, on Cassini's 203rd orbit, the spacecraft was about 1.9 million miles (3 million kilometers) from Saturn.

Saturn bizarre storm

Roseann Arabia created this adaptation of a Cassini raw image (#W00086402) showing the planet Saturn. The image seems to reveal the bizarre hexagon pattern of clouds on the planet's north pole that was discovered in 1988 from data collected during Voyager flybys. A raging storm churns at the center of the hexagon. One idea for how the structure formed and is maintained involves shallow atmospheric jets at the cloud level. Below the clouds, winds keep the hexagon shape and determine how fast it drifts, according to that model, which was published in June 2015 in Astrophysical Journal Letters.

"Editing and color enhancement of the image was performed in Photoshop using filtering, effects, masking, and several tool and brush techniques," Arabia said in a NASA statement.

Crescent Saturn

Stephane Calonnec created this image of Saturn from a raw Cassini image captured on March 12, 2014. She colorized it using standard Saturn colors. "I chose not to remove the blurry light from bottom as it is part of the original picture," Calonnec said in a NASA statement. "I've done it 'just for fun' and to test whether I could do a nice picture of a vessel's [spacecraft's] photo, not pretending scientific or artistic artwork. I just hope you will like it."

Saturn's colors are the result of the composition of its cloud layers, as well as their varying heights, according to NASA. The cloud layers consist mostly of ammonia ice crystals.

Mimas and the inner rings

This image, created by Maksim Kakitsev, shows Saturn's inner rings, the moon Mimas (at the bottom) and the F ring. "This true-color view was created from Cassini's raw images taken on Jan. 18, 2005 using the narrow angle camera and red, green, and blue filters."

Mimas, which looks eerily like the Death Star, the planet-destroying space weapon in "Star Wars," is the closest major moon to Saturn.

Saturn's swirling clouds

Kevin M. Gill produced this false-color view of Saturn's clouds from raw images that Cassini captured on July 20, 2016. For those with photo-tech know-how, Gill said: "I mapped the CB2 filtered image (.75 micron wavelength) to red, MT2 (.727 microns) to green and MT1 (.619 microns) to blue."

Bizarre hexagon on Saturn

"This is a true color view of Saturn's north polar region, taken by Cassini's Imaging Science Subsystem (ISS) on June 26, 2013," the producer Val Klavans said in a NASA statement. "Saturn's mysterious hexagon is visible in the center."

Klavans added: "This composite is made of images that were taken on June 26, 2013 and received on Earth June 27, 2013. The camera was pointing toward Saturn at approximately 402,383 miles (647,573 kilometers) away, and the images were taken using the CL1, RED, BL1 and GRN filters."

Enceladus feeding the E ring

Val Klavans also created this Cassini image, showing the Saturnian moon Enceladus inside the E ring. "On July 19, 2013, you waved at Saturn. The Cassini spacecraft was there to snap a photo of not only us, but the Saturn system," Klavans said.

"This composite is made of images that were taken on July 19, 2013 and received on Earth July 20, 2013. The camera was pointing toward SATURN-ERING at approximately 740,000miles (1,200,000 kilometers) away, and the images were taken using the CL1, RED, BL1 and GRN filters," he added in a statement.

On June 22, The Mars Society launched the second phase of its ambitious Mars 160 Twin Desert-Arctic Analog simulationto study how seven crewmembers could live, work and perform science on a true mission to Mars. Mars 160 crewmember Paul Knightly is chronicling the mission, which will spend 60 days in the Canadian arctic at the Flashline Mars Arctic Research Station (FMARS) on Devon Island after completing a similar 80-day mission at the Mars Desert Research Station (MDRS) in southern Utah in 2016. Here's his fourth dispatch from the mission: 

Why are we here? That's a question that all of us have encountered at some point in the buildup to the twin simulations of Mars 160. It's a fair question to ask, and you would probably get a different answer from each of us. We're all motivated for different reasons, but ultimately we are all united by a desire to see human bootprints on Mars within our lifetimes. So if any of our research over the course of Mars 160 contributes to advancing Mars exploration in some manner, then we will have succeeded and the mission will have been worth the months spent in isolation away from home.

For myself, I got involved in Mars 160 when I signed up late in 2013 to join a yearlong simulation to be carried out at FMARS as a part of the Mars Arctic 365 (MA365) mission. When I first signed up, I was fresh out of college and looking for an interesting way to combine my knowledge of geology with my love of space, without a focused research project in mind. But I soon developed a project that would fit the niche of the yearlong mission, and I applied. Several of us can trace our involvement in Mars 160 this way — Alexandre Mangeot, Anastasiya Stepanova, Yusuke Murakami, and Claude-Michel Laroche are all MA365 veterans like myself. [Inside Mars 160: The Mars Society's Red Planet Simulation in Pictures]

However, as with many things in life, things change, and so did our motivations for spending months in isolation in the arctic. In the course of planning for MA365, Mars 160 was born as an opportunity to compare two different analog sites and the type of science returned from each. Even though Mars 160 would shift the focus of the original mission we had signed up for, we quickly committed to the new goals set by the twin simulations and adjusted our projects accordingly.

In spite of all our pre-mission planning and in keeping with the spirit of the mission, there have been many things that we've encountered over the course of the mission that have piqued our interests that we hadn't originally planned on. After all, part of our mission is to fill in the knowledge gaps on what would make an actual mission to Mars run more efficiently.

Enter Alexandre Mangeot and Yusuke Murakami. Alexandre, our commander from France, is an engineer by training and is always looking for ways to improve things around the FMARS. Yusuke, from Japan, is an architect who has been traveling the world for the last decade to understand how people live and work in extreme environments. Their experiences working in extreme environments make it easier to identify problems and build better habitats for the first crewed missions to Mars. With goals like this, it is easy to see why they are such a good fit working together.

One moment of serendipitous research was spurred out of a desire by Alex to redesign the spacesuit backpacks at FMARS that have remained almost unchanged since the first missions here in the early 2000s. Teaming up with Yusuke, who brought 3D scanning equipment with him, they have built three-dimensional models of the spacesuits and are actively working to design the next generation of sim-suits that could be deployed on a future mission to FMARS. Advances in spacesuit design technology over the past decade also have allowed new tolerances to be applied to the new suit designs. This could translate to more ergonomically friendly designs that would make conducting field tasks, such as collecting geological or biological samples, easier and less burdensome.

You may ask: But couldn't these missions just as easily be performed in a laboratory setting closer to home to identify these problems? [How Will a Human Mars Base Work? NASA's Vision in Images]

Some of the engineering problems could be. But immersion in an analog environment is also important. The geology and biology here on Devon Island are similar to what one might find on Mars. The periglacial environment of the arctic and antarctic regions are the closest approximation we have on Earth to the temperatures and surface processes that dominate Mars today. This is a land shaped by the cold and ice.

The geological research of our mission has focused on periglacial features such as patterned ground that is known to occur on Mars. Study of these features in our time here has underscored how important water ice is in shaping the landscape. If a habitat is to be built in an area where the ice table is close to the Martian surface, consideration needs to be taken to how much heat is radiated out from the habitat. If heat radiation is not controlled, the heat could potentially melt the ice and render the habitat unstable.

Working in the field and in isolation also reinforces the mental conditions that astronauts on Mars would face. For this reason, a Twin EVA (extravehicular activity) study has been undertaken between both halves of Mars 160 that looks at the difference in work efficiency in field-science tasks between suited and non-suited EVAs. The study is led by Shannon Rupert — the principal investigator for Mars 160 — and through our field trials we hope to identify the strengths and weaknesses of each type of EVA, which could in turn aid in spacesuit design and procedural planning for science EVAs on future simulations and missions to Mars.

This boils down to the very essence of why these simulations are important. Would the engineering problems we've identified been noticed or investigated if it weren't for our mission? Would we be able to fully replicate what it's like to work on the surface of Mars in a spacesuit from the confines of a laboratory?

The answer to those questions is the same as to the question of why we would want to spend months on end in a small, remote habitat in the arctic. There are things to be learned about conducting a Mars mission that can only occur when immersed in a simulated mission. Mars simulations effectively supercharge the research and design efforts that ultimately feed into mission planning.

This concept of learning by immersion dates back to the days of Apollo when astronauts were training for their trips to the moon. They spent hours training in the field on Earth, donning the suits they would wear in space. In the process, they learned how to identify and sample different geological features of interest and how to perform different engineering tasks in their bulky EVA suits. Engineers were also able to tweak the suits over the course of these simulations if problems arose. As if learning how to walk in 1/6 of Earth's gravity wasn't going to be hard enough, living and working on the moon was going to be unlike anything ever experienced before. As the old saying goes, practice makes perfect. [Lunar Legacy: 45 Apollo Moon Mission Photos]

It is this legacy that we are a part of. While an exact date for a crewed Mars mission is not on NASA's (or anyone's) official schedule yet, we all hope that it will be soon. When the time comes to start training astronauts for the first series of missions to Mars, we will be ready whether we are the lucky ones to go or not. What we are learning right now at FMARS, MDRS and through related simulations is laying the groundwork for the Mars mission plans of tomorrow. The journey to Mars is just beginning.

Editor's note: To follow The Mars Society's Mars 160 mission and see daily photos and updates, visit the mission's website here: http://mars160.marssociety.org/. You can also follow the mission on Twitter @MDRSUpdates.

Paul Knightly is a geologist and PhD student at the Arkansas Center for Space and Planetary Sciences at the University of Arkansas in Fayetteville. He is a member of The Mars Society's Mars 160 Twin Desert-Arctic Analog simulation, where he is conducting geological field research to better understand the arctic environment and its implications for Mars. Follow The Mars Society on Twitter at @TheMarsSocietyand on Facebook. Original article on Space.com.

On June 22, The Mars Society launched the second phase of its ambitious Mars 160 Twin Desert-Arctic Analog simulation to study how seven crewmembers could live, work and perform science on a true mission to Mars. Mars 160 crewmember Paul Knightly is chronicling the mission, which will spend 60 days in the Canadian arctic at the Flashline Mars Arctic Research Station (FMARS) on Devon Island after completing a similar 80-day mission at the Mars Desert Research Station (MDRS) in southern Utah in 2016. Here's his third dispatch from the mission:

This week I figured I would give you a tour of our home on "Mars" — the Flashline Mars Arctic Research Station, or FMARS for short. Let's start from the outside and work our way inside. At 2 stories tall and 25 feet (8 meters) in diameter, FMARS predates and is nearly identical to its sister station in Utah where we spent the first half of our mission, the Mars Desert Research Station (MDRS). 

Looking around from outside the station, it is easy to see why this location was selected. As we walked up to FMARS for the first time last month, it felt like I had been transported into an image captured by one of the Mars rovers. Large boulders are strewn about the polar desert without any vegetation in sight. Only a few species of lichen and flowers are hardy enough to survive in this harsh climate, and the few species of animals that call Devon Island home have made themselves scarce in our presence. And then there's the six of us living in a two-story habitat on the rim of an impact crater. [Inside Mars 160: The Mars Society's Red Planet Simulation in Pictures]

Just inside the main airlock on the first floor is the EVA Preparation Room, where we get ready for our extravehicular activities and store our spacesuits. This room leads into the rest of the first floor, which consists of lab space and work benches where we prepare samples and work on engineering problems including spacesuit maintenance and equipment repair. The bathroom and shower are behind the engineering work space — but more on that later.

Climbing a ladder leads to the second floor that consists of the main living area, including the kitchen and our state rooms. In the middle of the room, a kitchen table doubles as a conference table, around which stories and meals are shared and preparations are made for the day's field activities. As with many homes, a lot of life happens in our kitchen at FMARS.

Between our time on the Mars 160 mission and other missions to MDRS, we have all found that meal preparation and fixed eating times are essential to the emotional health of the crew. Food is an interactive experience that ensures the entire crew is involved in at least a few shared activities and moments each day. We all generally prepare at least one major meal (lunch or dinner) per week, ranging anywhere from soup at lunch to a minor feast at dinner. 

In just the past week, we have tested the culinary limits of our food supply. I cooked up a taco night on Saturday, which required me to make tortillas from scratch and to use Spam as a stand in for beef. Call it a Tex-Mex/Martian fusion dish. Then, on Monday, Yusuke spent the better part of the day preparing a dish he called "Red Water," which was a mix of almost everything in the kitchen minus the sink. I would call it a blend between curry and chili, but it was surprisingly tasty with a generally sweet and rich flavor. [Mars 160 Coverage: Training for a Manned Mission to Mars]

A meal that we look forward to twice per week comes courtesy of Anastasiya, who brought with her a supply of Russian space food courtesy of Spacefood Laboratory, based in Moscow. Spacefood Laboratory has been supplying food to the Russian space program since the 1950s and has recently expanded its market to include outdoor enthusiasts and rescue crews that all benefit from the easily prepared and nutritious dishes. The meals are my first introduction to the Russian palette, and dishes have ranged from borscht soup to a dessert of cottage cheese with sea-buckthorn. Naturally, almost all of these dishes come out of a tube — just as astronauts and cosmonauts would find them served up on the International Space Station(ISS).

Back to the tour of FMARS. Each person sleeps in a state room that leads into the kitchen and consists of a single bunk bed with adjacent space for clothes and personal items. Some walk-in closets are bigger than our state rooms, but on a mission to Mars space is critical, and the cramped quarters are a worthwhile price to pay for the sake of exploration. The rooms are big enough to provide us with private space when we need it, but much of our daily work happens out in the open. 

Above the state rooms is an attic where we can store extra food and supplies in addition to the water basin. Our water supply comes from a freshwater stream fed by snow melt that is about 0.6 miles (1 kilometer) from FMARS. The crystal-clear water is probably clean enough to drink without any additional filtration, but we boil all of our drinking water anyway to be safe. Water must be collected manually with the help of our ATVs every couple of days and is done "out of sim" in normal cold-weather gear. Once it is brought back to FMARS, a cistern in the EVA Prep Room is filled and then pumped to our upstairs water basin. From the basin, the water is then distributed to the kitchen and bathroom through a gravity and pump-on-demand system.

Which leads us back downstairs to the bathroom. People always want to know how astronauts "go" in space. Our bathroom at FMARS actually consists of two separate rooms for the toilet and shower. The shower is like any you might find in a normal house. It is attached to a water heater that we turn on during our weekly shower days — just one shower per person, per week here at FMARS. Daily hygiene is handled by a combination of no-rinse shampoo, baby wipes, and the occasional sponge bath. Laundry is a more difficult task that is usually performed using the shower as well, but without a dryer, clothes must be hung up to dry.

With all fanfare reserved for the end of our tour, we arrive at the toilet. Astronauts traveling to Mars will have to contend with human waste storage and disposal, which left unchecked could be quite voluminous for a crew of six or more on a two-year roundtrip mission. While MDRS is equipped with a standard septic system, waste handling at FMARS is actually more analogous to the constraints of a surface mission to Mars. [How Will a Human Mars Base Work? NASA's Vision in Images]

At FMARS, waste is segregated by liquids and solids. Liquid waste is stored in 55-gallon drums that are flown out at the end of the mission, and solid waste is burned in an on-site incinerator with other solid trash. This "leave no trace" mentality of wilderness exploration will also apply to the first missions to Mars, and is already being tested today. For instance, on the ISS, liquid waste is now being recycled into water usable for drinking. Solid waste on a Mars mission could perhaps be recycled into fertilizer to grow plants; otherwise, a storage and disposal system will need to be devised for early missions until infrastructure is built to handle it on a larger, municipal scale.

That concludes today's tour of FMARS! I hope you've enjoyed this insight into our home on "Mars." It may not have all the luxuries of a modern home, but it is helping us to prepare for what the first astronauts will need as we venture farther into the solar system.  

Editor's note: To follow The Mars Society's Mars 160 mission and see daily photos and updates, visit the mission's website here: http://mars160.marssociety.org/. You can also follow the mission on Twitter @MDRSUpdates.

Paul Knightly is a geologist and PhD student at the Arkansas Center for Space and Planetary Sciences at the University of Arkansas in Fayetteville. He is a member of The Mars Society's Mars 160 Twin Desert-Arctic Analog simulation, where he is conducting geological field research to better understand the arctic environment and its implications for Mars. Follow The Mars Society on Twitter at @TheMarsSociety and on Facebook. Original article on Space.com.

On June 22, The Mars Society launched the second phase of its ambitious Mars 160 Twin Desert-Arctic Analog simulation to study how seven crewmembers could live, work and perform science on a true mission to Mars. Mars 160 crewmember Paul Knightly is chronicling the mission, which will spend 60 days in the Canadian arctic at the Flashline Mars Arctic Research Station (FMARS) on Devon Island after completing a similar 80-day mission at the Mars Desert Research Station (MDRS) in southern Utah in 2016. Here's his second dispatch from the mission: 

Although our mission started on June 22 when we arrived in Yellowknife and began making final preparations for our simulation in the arctic, we didn't begin the second half of our Mars mission simulation until July 20 due to the weather. In spite of this delay, the crew has been making up for lost time and catching up on research projects delayed by our late arrival.

Mars 160 is unique from past mission simulations in that science return is the main variable being measured between the arctic and desert analog facilities operated by the Mars Society. This has given us as the crew the flexibility to pursue more aggressive field investigations than might normally be possible when faced with analog Mars mission constraints. [Inside Mars 160: The Mars Society's Red Planet Simulation in Pictures]

The first two extravehicular activities (EVAs) that we conducted were "in-sim," which means they were conducted under full Mars mission simulation constraints, including donning a spacesuit and waiting for our airlock to depressurize before going outside. The spacesuits limit our mobility and make normal tasks such as opening a sample bag or operating a hand tool much more of a challenge. Astronauts training for EVAs on the space station and, in the future, for surface exploration of Mars will have to confront these challenges.

However, we are also not on Mars — we don't face deadly depressurization and cold on the other side of our helmets. We are sitting on the rim of an ancient impact crater that is home to geological and biological processes that make for interesting points of Mars analog study beyond the context of our simulated Mars mission. So, if we are facing inclement weather or activities that might be dangerous or inhibited as a result of wearing spacesuits, we conduct so-called "out-of-sim" EVAs in normal cold-weather gear suitable for the arctic summer. These EVAs are noted and factor into the overall science productivity of the mission by comparing in-sim and out-of-sim activities.

As a result of rain that limits our visibility while wearing our helmets, many of our EVAs over the past week have been conducted out-of-sim. Despite this deviation from normal simulation conditions, it has not spoiled the spirit of the mission. None of us have ever been to Devon Island or this far north in the arctic, so even though not conducted under simulation constraints, these scouting EVAs are the essence of true exploration. Walking over every hill reveals a landscape seen by few and often raises more questions about this exotic area than it provides answers.

Astronauts on Mars will face a similar dilemma, and this scouting process is ultimately what drives exploration forward. With so much area to explore, how do we choose which targets are the most scientifically valuable, and how do we prioritize them against each other? These are topics of conversation on a daily basis at FMARS during our daily briefings.

There has been a communal sense of relief in being able to begin our field science projects over the past week, and, while we are keeping an aggressive EVA schedule for the remainder of the mission in order to stay on track, we have made sure to take time to rest. Our first day off came on July 22, which saw frequent drenching rains persisting throughout the day. Work is sometimes hard to put down, but once some tentative plans had been made for the next day, we settled in to a mix of our own activities as well as group activities to help recharge our batteries. [Mars 160 Coverage: Training for a Manned Mission to Mars]

Shortly after lunch, Yusuke Murakami broke out a box of Origami paper with national flags printed on each sheet. Yusuke is a jack of all trades who has spent time in extreme places, including Antarctica and the Mount Everest Base Camp, and has been quick to teach us all new skills. Whether it was how to tie different knots while we waited in Resolute or how to make paper swans on a rainy Saturday, there has been no shortage of activity ideas from him.

Anastasiya Stepanova, our Russian crewmate, found a bread maker in the attic of FMARS and promptly went to work baking our first loaf of "Martian bread." During both halves of the mission here and at MDRS, the smell of bread and the feeling of community that forms around the table as fresh bread is broken quickly lift the spirits of the crew. Once a fresh loaf is ready, we often sit around the table drinking coffee and tea, swapping stories about our lives back home and of course talking of our common area of interest: Mars.

Being away from home for as long as we have also means celebrating some holidays and birthdays over the course of our mission. While we were waiting in Resolute, we marked Canada Day by joining the local parade through town, and just a few days later I marked the 4th of July under snowy skies from our remote hotel. We will have two birthdays to mark at FMARS — Yusuke's and my own. Yusuke's was on Monday and, since this was his first Martian birthday, we made sure that we celebrated his true age in Mars years, with each Mars year making for about two Earth years. Using this math, he is celebrating his 19th birthday and I will be celebrating my 14th!

So how does one celebrate a birthday on Mars? It is a mix of good-natured humor and making the most of what you have available. For Yusuke's birthday, a toy water gun was found in the attic, left from a previous mission, and given to him as a gift from the entire crew. A large birthday dinner of cabanera was cooked up using available ingredients by our French commander, Alexandre Mangeot. The birthday desert was kulfi, a traditional Indian dish which was prepared by Anushree Srivastava, our crewmate from India. The evening was spent around the table, laughing and eating as we have become accustomed to on our journey.

We have about three and a half more weeks left in our mission to Mars on Earth here in the Canadian arctic. The forecast is calling for more rain and snow in the coming days, but we are making the most of the situation and gathering as much field data as we can for our respective analog research projects. Despite the dreary weather, there is never a dull moment around the station and the crew remains in good spirits.

Editor's note: To follow The Mars Society's Mars 160 mission and see daily photos and updates, visit the mission's website here: http://mars160.marssociety.org/. You can also follow the mission on Twitter @MDRSUpdates.

Paul Knightly is a geologist and PhD student at the Arkansas Center for Space and Planetary Sciences at the University of Arkansas in Fayetteville. He is a member of The Mars Society's Mars 160 Twin Desert-Arctic Analog simulation, where he is conducting geological field research to better understand the arctic environment and its implications for Mars. Follow The Mars Society on Twitter at @TheMarsSociety and on Facebook. Original article on Space.com.

One of the largest icebergs ever recorded, packing about a trillion tons of ice or enough to fill up two Lake Eries, has just split off from Antarctica, in a much anticipated, though not celebrated, calving event. 

A section of the Larsen C ice shelf with an area of 2,240 square miles (5,800 square kilometers) finally broke away some time between July 10 and today (July 12), scientists with the U.K.-based MIDAS Project, an Antarctic research group, reported today.

Scientists discovered the birth of this iceberg in data collected by an instrument aboard NASA's Aqua satellite, called MODIS, which takes thermal infrared images. [In Photos: Antarctica's Larsen C Ice Shelf Through Time]

The iceberg was expected, though scientists didn't know when the crack in the ice sheet would finally release the floating chunk. The rift in the Larsen C ice shelf — the fourth-largest shelf in Antarctica — first showed itself in 2014, but it wasn't until November 2016 that satellite measurements revealed it had grown to more than 300 feet (91 m) in width and 70 miles (112 km) in length. The most recent measurements from this summer put the rift at 124 miles (200 km) long, with the now-calved iceberg hanging on by a thread; just 3 miles (5 km) of ice connected it with the rest of the ice shelf.

Even though the towering berg weighs more than 1.1 trillion tons (1 trillion metric tons), it won't have a direct impact on sea-level rise. That's because the ice was already floating on the sea. Even so, when an iceberg like this one calves, it can speed up the collapse of the rest of the ice shelf — the new iceberg reduced the area of the Larsen C ice shelf by 12 percent. Also, the ice shelf serves as a barrier to the land-based glacier that feeds the ice shelf; as that barrier diminishes, there's more of a chance for the ice behind it to collapse into the sea, MIDAS researchers said.   

And it's this once-land-based ice that would impact sea levels, researchers say.

"Although this is a natural event, and we're not aware of any link to human-induced climate change, this puts the ice shelf in a very vulnerable position," Martin O’Leary, a Swansea University glaciologist and member of the MIDAS project team, said in a statement. "This is the furthest back that the ice front has been in recorded history. We're going to be watching very carefully for signs that the rest of the shelf is becoming unstable."

As for what will happen to this huge chunk of ice, nobody knows at the moment.

"The iceberg is one of the largest recorded and its future progress is difficult to predict," Adrian Luckman of Swansea University, lead investigator of the MIDAS project, said in the statement. "It may remain in one piece, but is more likely to break into fragments. Some of the ice may remain in the area for decades, while parts of the iceberg may drift north into warmer waters."

Original article on Live Science.