On Oct. 29, 1991, the Galileo spacecraft flew by the asteroid Gaspra on its way to Jupiter. Gaspra was the first asteroid to ever be visited by a spacecraft.

Gaspra orbits near the inner edge of the asteroid belt. The Galileo spacecraft had been travelling through the asteroid belt for about two months before it reached Gaspra. Galileo was 990 miles (1,593 kilometers) away from Gaspra when it whizzed by, and it was travelling at a relative speed of about 5 miles (8 km) per second.

The spacecraft took several photos of the asteroid and used an instrument called the Near-Infrared Mapping Spectrometer to study its chemical composition and other physical properties. Galileo determined that Gaspra has an irregular and elongated shape measuring about 12 miles long and 7 miles wide. The images revealed that Gaspra was also covered in craters. Because Galileo was too far away for Gaspra's gravity to affect it, the spacecraft was not able to determine the asteroid's mass.

Why it mattered

The Galileo spacecraft's flyby of Gaspra was a pitstop near the midpoint of its 6-year journey to Jupiter, the largest planet in our solar system. NASA launched Galileo toward Jupiter in October 1989, with the probe swinging by Venus and Earth in 1990 before its encounter with Gaspra.

The Gaspra flyby was the first asteroid flyby in history, with Galileo approaching to just under 1,000 miles (1,601 kilometers) while flying at a whopping 18,000 mph. Galileo's photos of Gaspra "revealed a cratered, complex, irregular body about 20 by 12 by 11 kilometers (12.4 by 7.4 by 6.8 miles), with a thin covering of dust and rubble," NASA wrote in an overview.

"The picture we get of Gaspra is one of something that has suffered a lot during its history," the UPI press service quoted Joseph Veverka, a Galileo imaging team member, as saying at the time. "We suspect that this is the survivor of a series of catastrophic collisions in the past."

Galileo would go on to fly by Earth a second time in 1992, then swing close by the asteroid Ida in 1993 before finally arriving at Jupiter in 1995. Along the way, the probe was in the right place at the right time to watch as the Comet Shoemaker-Levy 9 broke into pieces and crashed into Jupiter in July 1994.

Since Galileo's historic first asteroid flyby, NASA and other space agencies have gone on to land on asteroids (like NEAR on asteroid Eros), collect samples of asteroids and return them to Earth (like NASA's OSIRIS-REx and Japan's Hayabusa probes), and have even intentionally crashed probes into asteroids (like NASA's DART asteroid impact mission) to test planetary protection techniques.

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Earth almost always has more than one moon. The others are just very small, and they never stay long — but they could provide accessible and unique insights into the solar system.

Temporary satellites, or mini-moons, are small asteroids that wander into Earth’s neighborhood and get captured briefly by our planet’s gravity. A typical one stays about nine months and circles Earth roughly three times before escaping back into orbit around the sun, Grigori Fedorets of Finland's University of Helsinki said in a presentation at the Europlanet Science Congress (EPSC) 2026 in The Hague in September.

Fedorets' modeling suggests that the largest mini-moon around Earth at any given moment is typically only about 75 centimeters (30 inches) across. An asteroid about 3 meters (10 feet) wide should be captured every 10 to 20 years.

"This is not just a theoretical construct. There is observational evidence," Fedorets said. Only two mini-moons have been confirmed to date, however — 2006 RH120 and 2020 CD3, both discovered by the Catalina Sky Survey in Arizona. Two fireballs, seen over the Czech Republic in 2013 and Australia in 2016, were traced back to objects that had been in geocentric orbits. Two more asteroids, 2022 NX1 and 2024 PT5, were captured only briefly, without completing a full orbit.

Fedorets noted a potential third mini-moon — the recently detected Sar2901, which could also be an artificial object. Sar2901 has since faded from view but should be observable again around mid-to-late November, according to the Minor Planet Center.

Small rocks, big questions

Mini-moons are so small that scientists know little about them. For objects between 1 and 10 meters (3.3 to 33 feet) across, models of the near-Earth asteroid population disagree with the numbers suggested by records of fireballs in Earth's atmosphere. Mini-moons sit right in that gap, so finding more of them should show which picture is right.

They may also reveal how much of the material in Earth’s neighborhood traces its origin back to our moon, as some small asteroids may be chunks of the lunar surface blasted into space by impacts. During the temporary flyby of asteroid 2024 PT5, for example, scientists found its spectrum to be closer to lunar rock than to typical asteroids, according to a 2025 study led by Theodore Kareta, which Fedorets described as the strongest evidence yet for lunar ejecta among Earth's small neighbors.

Kamo’oalewa, a much larger asteroid and quasi-moon of Earth, at which China’s Tianwen-2 mission arrived in July, has been the subject of debate over possible lunar or asteroidal origins.

Rubin game-changer and budget sample returns

The transformative Vera C. Rubin Observatory's 10-year Legacy Survey of Space and Time (LSST) should find many more mini-moons, though further work will be needed. On its own, Fedorets estimates, the survey should catch a mini-moon about once every two years.

Fedorets and colleagues are setting up a dedicated system running on a virtual server at Finland's Center for Scientific Computing, to sift Rubin's alerts through the ANTARES real-time astronomical data broker to flag potential mini-moons for follow-up observations, which could raise detections to two or three per year.

Making regular discoveries could open doors for future missions, providing targets for relatively easy, low-cost asteroid sample-return missions. Mini-moons’ proximity to Earth, and their low relative speeds, means less rocket propellant is needed to get out to these diminutive targets and back to Earth.

Initially, Fedorets envisions cubesat tech demo missions, which would pave the way for mid-sized missions that could collect samples. He sees the Tianwen-2 low-energy sample mission as a potential stepping stone to resource utilization, while also noting that, at the higher end of the scale, there have been programs such as NASA’s cancelled Asteroid Redirect Mission (ARM) and plans by, for example, TransAstra to put a 100-ton asteroid into a stable orbit around Earth.

"This is not sci-fi," Fedorets said. "These people are actually thinking about this kind of stuff."

The short warning times and instability of the orbits of mini-moons dictates potential mission profiles. A spacecraft could wait in Earth-moon space, ready to head for a newly found mini-moon, similar to how ESA's Comet Interceptor will launch and then wait for a suitable comet to study. Asteroids could also be nudged into more stable orbits, allowing more extensive future missions.

"LSST is now online, and over the next 10 years, we are expected to find many more of these temporary moons," Fedorets said. Regular discoveries could pave the way for exploration in the early 2030s and sampling missions later in the decade.

On Sept. 30, NASA formally concluded OSIRIS-REx, the historic first U.S. mission to pluck a pristine piece of an asteroid and deliver it safely back to Earth.

The van-sized OSIRIS-REx spacecraft — whose name is short for Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer — visited and sampled Bennu, an ancient space rock holding pristine remnants from the dawn of our solar system more than 4.5 billion years ago. Among those cosmic relics are raw organic building blocks, the kind that may have seeded life on Earth.

"I have known this day was coming for a long time, but it is still difficult to see it arrive," OSIRIS-REx Principal Investigator Dante Lauretta, who's based at the University of Arizona, said in a post on LinkedIn. "I feel enormous pride in what we accomplished together, and real sadness that this journey has come to an end."

For the mission team, the farewell capped a decade of high-stakes engineering, on-the-fly troubleshooting and nail-biting close calls that ultimately delivered to Earth the largest asteroid sample ever collected in space, one that held secrets from the early solar system.

Long before launch, the team faced obstacles that nearly thwarted the endeavor — chiefly, two rejections from NASA — before finally securing the green light for the $1 billion project under the New Frontiers Program in 2011.

When OSIRIS-REx launched on Sept. 8, 2016, on a two-year journey across the inner solar system, Bennu was little more than a point of light in telescopes. Scientists expected the asteroid’s surface to be a smooth, sandy sphere where OSIRIS-REx could seamlessly touch down. Much to their surprise, however, when the probe arrived at the asteroid in late 2018, it revealed Bennu to be a treacherous, loosely bound amalgamation of jagged boulders.

"Our expectations about the asteroid's surface were completely wrong," Lauretta said in an Oct. 7 statement from the University of Arizona. "There was no obvious place to collect a sample anywhere."

When OSIRIS-REx touched down on a small crater named Nightingale, Bennu offered so little structural resistance that scientists said its surface reacted more like fluid than a hard, rocky shell. The spacecraft's sampling head sank directly into the asteroid, stopping after burrowing 20 inches (51 centimeters) deep by firing its thrusters at the right time to pull away, with the precious sample in hand.

Then came another nail-biting moment: The sample collector lid got jammed in a partially open position because so much material was scooped up, allowing fragments of the precious cargo to escape. In a race against time to prevent further loss, the mission team quickly stowed the sampler head directly inside the return capsule, securing the cosmic treasure for its journey back to Earth.

Even the final return to Earth, on Sept. 24, 2023, kept the team on edge: A parachute failed to deploy properly during reentry, forcing a tense but ultimately safe landing in the Utah desert.

"Successful exploration missions are not those that avoid surprises; they are those that are deliberately designed to adapt to them," Lauretta said in the statement, quoting a line from the mission's final report to NASA.

"That certainly describes OSIRIS-REx," he said. "Again and again, the mission presented us with circumstances we had not expected, and again and again, this team found a way forward."

The mission's triumphs began long before the samples reached Earth. For example, the probe set a Guinness World Record when it slid into orbit around the 1,610-foot-wide (490 meters) Bennu, which became the smallest object ever circled by a spacecraft.

The scientific payoff that followed included remote-sensing work that confirmed Bennu's surface is coated in carbon-bearing compounds. Those observations also revealed that Bennu was once part of a much larger, water-rich parent asteroid that shattered in a catastrophic collision in the main asteroid belt between Mars and Jupiter.

The returned sample — which weighs 4.29 ounces (121.6 grams) here on Earth, more than twice the mission's requirement — continues to thrill and occupy scientists.

A wave of research papers, now topping 200, continues to piece together the composition and history of the ancient space rock. Among other findings, Bennu's pristine material has revealed amino acids and sugars that, on Earth, are essential for life, alongside a history of exposure to liquid water that could have served as the "broth" for these compounds to interact.

More discoveries are likely to come. Most of the returned Bennu sample is being preserved for future generations of scientists, who will study it "with questions and instruments we cannot yet anticipate," Lauretta said in the statement.

Though its OSIRIS-REx chapter is closed, the spacecraft itself is far from retired. Renamed OSIRIS-APEX (OSIRIS-APophis EXplorer), the probe is using its remaining propellant to head toward Apophis, another near-Earth asteroid and a different type of space rock from Bennu. It is scheduled to arrive in 2029.

Editor's note: Japan launched its bold MMX sample-return mission to the Mars moon Phobos on Oct. 19) at 3:41 p.m. EDT (1941 GMT).
Watch a replay of the liftoff and read our launch story here.

Japan's mission to Mars is one of the most ambitious in spaceflight history. It aims to become the first spacecraft to return to Earth from Mars orbit, carrying with it the first-ever samples from the Red Planet system.

The mission, known as Martian Moons eXploration (MMX), is a first-of-its-kind endeavor to study the origin of Mars' moons Phobos and Deimos. The robust undertaking includes a landing on Phobos to collect the samples — which will likely be the first from the Mars system to return to Earth — and a search for evidence that could shed light on events during the formation of the solar system billions of years ago.

MMX launched on an H3 rocket from Japan's Tanegashima Space Center on Monday (Oct. 19) at 3:41 p.m. EDT (1941 GMT; 4:41 a.m. local time in Japan, Oct. 20). After a 10-month journey to reach Mars, the spacecraft will spend about three years studying Phobos, deploying a rover and landing to collect its samples. The mission will then shift its focus to Deimos for a series of flybys before departing for Earth in November 2030. If all goes according to plan, the MMX sample-return capsule is scheduled to land in Australia in 2031.

The spacecraft

The MMX spacecraft is comprised of three main parts, as well as a small rover. After release from its H3 launch vehicle, a propulsion module will provide the boost to put MMX on course for Mars. MMX's main exploration module carries the microwave-size IDEFIX rover and most of the mission's scientific instruments, while the return module houses the sample-return capsule.

Japan's Mitsubishi Electric built MMX's three main modules, with the French space agency CNES (Centre National d'Études Spatiales) and Germany's DLR (Deutsches Zentrum für Luft-und Raumfahrt) jointly developing IDEFIX. The little rover is named for a dog in the 1960s French comic "Asterix," in a nod to the country's first satellite, Astérix, which launched in 1965.

IDEFIX carries a suite of cameras, as well as the Raman Spectrometer for MMX (RAX) and miniaturized radiometer (miniRAD) instruments to analyze Phobos' surface composition and temperature.

Most of MMX's scientific instruments are housed on the exploration module, like NASA's Mars-moon Exploration with Gamma rays and Neutrons (MEGANE, pronounced "meh-gah-nay") device, a gamma-ray and neutron spectrometer built by the Johns Hopkins Applied Physics Laboratory (APL), and France's MIRS (MMX InfraRed Spectrometer) instrument.

The exploration module also houses the Japanese-built TENGOO (TElescopic Nadir imager for GeOmOrphology) tight-zoom camera, wide-angle OROCHI (Optical RadiOmeter composed of CHromatic Imagers) multispectral camera, laser altimeter (LIDAR) and Mass Spectrum Analyzer (MSA). The return module, meanwhile, carries Japan's Circum-Martian Dust Monitor (CMDM) and Interplanetary Radiation Environment Monitor (IREM).

The mission

MMX will arrive in orbit around Mars in August 2027, at which point it will shed its propulsion module and transition into a quasi-satellite orbit (QSO) around Phobos that allows the probe to fly in a sort of formation with the small, asteroid-sized moon as they both circle the Red Planet.

The spacecraft will spend its first few months in the Martian system observing Phobos from different altitudes, using its TENGOO and OROCHI cameras, LIDAR and MSA to map the moon's surface, study its composition and select potential landing sites.

IDEFIX will be released in late 2028 or early 2029, during the first of two MMX landing rehearsals, at about 130 feet (40 meters) above Phobos. Due to the 14-mile-wide (22 kilometers) moon's extremely low gravity, the rover will be able free-fall to the surface damage-free (hopefully), right itself after a few bounces and begin exploring to gather data on the terrain and surface conditions.

MMX sample collection could begin as early as December 2028, the acting director of NASA's Planetary Science Division, Lindsay Hays, said during a mission briefing on Oct. 15. The spacecraft will attempt two collection landings, with its exploration and return modules descending and returning to orbit as one vehicle.

On Phobos' surface, two different sampling mechanisms — the Corer Sampling Mechanism (C-sampler) and Pneumatic Sampling Mechanism (P-sampler) — will extract and collect at least 10 grams (0.35 ounces) of material for stowage inside the spacecraft's return capsule before MMX lifts off again for orbit. After its first touchdown and sample collection, MMX will return to QSO near Phobos before descending to a second landing site for a similar attempt and subsequent return to orbit.

MMX will end its observations of Phobos after about three years focused on the Martian moon, and will transition into a higher, resonant orbit around Mars in 2030. That course will repeatedly intersect Deimos' path for a series of flybys to collect and compare data with those from Phobos observations as scientists aim to investigate the moons' origins.

Near the end of 2030, the exploration module will separate, leaving the return module to fire its engine out of Mars' gravitational influence and begin an eight-month journey back to Earth with the collected samples. As MMX closes the last stretch of void during its approach to Earth in 2031, the sample-return capsule will separate and enter the atmosphere for a targeted parachute landing in Australia's Woomera region, where its contents will be recovered for laboratory analysis by Japan and its mission partners.

Phobos and Deimos

Those samples, and the data collected by MMX, could tell scientists a lot — about the moons' composition, geography and, perhaps most importantly, how they came to exist in the first place. There are two leading theories for Phobos and Deimos' origins, both of which point to very different versions of ancient Martian history.

"Phobos and Deimos are interesting, but not just in their own right. Their presence is a key piece of the larger story of the Mars system," said Tom Statler, MMX program executive and scientist in NASA's Planetary Science Division, during the Oct. 15 mission briefing. "By uncovering the moons' origin, we'll gain new insights into the history of both Mars and Earth, especially those events that shaped both planets billions of years ago and helped create the worlds we see today."

Both Phobos and Deimos are relatively small and irregularly shaped, and bear several resemblances and spectral characteristics to primitive D-type asteroids — ancient bodies thought to preserve material dating back to the solar system's formation about 4.6 billion years ago. Those similarities suggest Phobos and Deimos may have formed elsewhere in the solar system and were later captured by Mars' gravity.

Their near-circular, equatorially-aligned orbits around the Red Planet, however, somewhat complicate that theory. For example, a captured asteroid would be much more likely to have entered an elongated and tilted orbit akin to the direction and velocity of its original approach, scientists say. A competing hypothesis, therefore, offers a much more violent, but somewhat familiar, narrative for the moons' origins.

An enormous collision with ancient Mars could have blasted material into orbit to form a debris disk from which the two moons eventually coalesced. Such a process, which would be similar to the formation of Earth's moon, could explain their circular, equatorial orbits.

The contradicting geological and orbital observations for Phobos and Deimos collected to date have prevented scientists from definitively establishing one hypothesis over the other. MMX aims to provide an answer.

"It's two totally different lines of evidence that point in two different directions. That's what makes it an interesting puzzle," Statler said. Several theories have also been presented for hybrid scenarios combining the two, he added.

"There's all kinds of different ways, all kinds of different combinations of those two basic scenarios," Statler explained. "But that's the puzzle from the start, the two seemingly contradictory lines of evidence that are pointing us to what … the real history was, but we don't know what it is yet."

The science

Each theory for where Mars' moons came from predicts different chemical characteristics for their surfaces. Presumably, captured asteroids would preserve chemical signatures of material originating elsewhere in the solar system, potentially rich in volatile elements like hydrogen. Moons formed through a planetary impact, however, would contain a mixture of Mars and impact material, altered by the intense heat of such a violent collision.

Determining which scenario is more likely could reveal whether Mars experienced a massive moon-forming collision or acquired its moons from elsewhere in the early solar system. Either answer could offer new insights into the planet's evolution and the events that shaped the terrestrial planets like Earth billions of years ago, mission team members say.

"At this point, we know nothing about the composition of Phobos," David Lawrence, MEGANE principal investigator at APL, said during the Oct. 15 briefing. "We have information about mineralogy, but no elemental composition. And so, elements are really a key way to get at some of these foundational questions."

MMX's scientific suite has been carefully calibrated to make those determinations. The cameras and sensors on the MMX exploration module's TENGOO, OROCHI and LIDAR instruments will map Phobos' terrain, geological features and variations in surface materials from orbit, to provide clues about the moon's formation and evolution. Complementing those measurements, MIRS is designed to detect and classify Phobos' surface minerals and search for organic compounds to further differentiate its possible origin as an asteroid or ancient chunk of Mars.

The RAX spectrometer and miniRAD instrument aboard IDEFIX will add localized context to those observations by examining surface mineralogy and their thermal properties up close.

Back in orbit, NASA's MEGANE instrument will measure Phobos' elemental composition through gamma-ray and neutron spectroscopy that can scan tens of centimeters beneath the moon's surface for signs of volatile elements. Higher abundances of hydrogen, chlorine, sodium and potassium, for instance, would favor the asteroid-capture hypothesis, while lower abundances of those compounds could point to the heat and chemical deterioration associated with a planetary impact.

"In Japanese, 'megane' means eyeglasses," Lawrence said. "So we like to think of MEGANE as being an instrument that will look at Phobos with gamma ray and neutron glasses."

When compared to the samples MMX will return to Earth, MEGANE's findings could help scientists determine if volatile depletion found on Phobos reflects the intense heat of a post-impact formation or billions of years of subsequent erosion from the natural effects of space exposure.

MSA, meanwhile, will measure charged particles around Phobos, searching for evidence of subsurface ice and investigating how solar wind exposure has altered the moon's surface. It will also study atmospheric particles escaping from Mars. CMDM will measure dust around Mars, including particles potentially ejected from its moons by impacts.

Comparative observations of Deimos after MMX's final departure from Phobos will help establish whether the moons share similar compositions and, potentially, a common origin.

Once safely returned to Earth, laboratory analysis of the Phobos samples will allow scientists to examine chemical composition and mineralogy with a precision beyond that of MMX's onboard instruments. Tests like isotopic analyses — measuring subtle differences in the atomic makeup of elements — can help identify the samples' origins by comparing their chemical fingerprints with those of Martian rocks and asteroid material.

JAXA (Japan Aerospace Exploration Agency) scientists think some returned material could even originate from Mars itself, deposited on Phobos after ancient asteroid impacts blasted rocks off the Red Planet's surface, potentially holding evidence of its geological past.

International effort

The JAXA-led mission represents interagency partnerships with NASA and the European Space Agency (ESA), which are providing hardware and communications support through the Deep Space and Estrack networks.

NASA's contributions to MMX also include MEGANE, the Honeybee Robotics-built P-sampler, and an approximately $87 million investment through the end of the mission. NASA is funding the United States scientists on the MMX team, who will, alongside NASA's astromaterials experts, "be fully involved in the examination and scientific analysis of the Phobos samples when they are delivered to Earth," Hays said during the mission briefing. "We get all of the value and all of the scientific participation at a lower cost total [than funding the entire mission]."

For its role, NASA will receive at least 15% of the returned samples, with materials to be maintained at the agency's Johnson Space Center in Houston for analysis and long-term preservation. To that end, MMX's scientific impact could extend far beyond the mission's conclusion.

"The Phobos samples will be historic," Statler said, with the potential "for future research to answer the questions we don't even know yet how to ask."

The United Arab Emirates (UAE) has moved a step closer to launching its second-ever interplanetary mission — an ambitious, eight-year exploration of seven asteroids between Mars and Jupiter that will culminate with a landing on the mysteriously red asteroid 269 Justitia.

The mission team unveiled a half-scale model of the homegrown probe that will make that landing during an Oct. 1 press conference in Abu Dhabi, the capital of the UAE. The autonomous craft will ride attached to the main spacecraft MBR Explorer, named after Sheikh Mohammed bin Rashid al-Maktoum, the ruler of Dubai and the UAE's prime minister.

The flight-ready lander is being kept pristine in a vacuum chamber in the capital before being transported to Colorado by Etihad Airways, officials said, where it will be integrated with the main spacecraft, which was developed by the UAE Space Agency.

If all goes to plan, the mission will lift off from Japan in March 2028, kicking off the Emirates Mission to the Asteroid Belt (EMA). The project is an ambitious follow-up to the UAE Space Agency's Hope Mars orbiter, which has been studying the Red Planet since 2021.

"It's a proud moment for us here at the UAE," said Faisal al-Bannai, the secretary general of the Advanced Technology Research Council in Abu Dhabi.

'We don't know what we're going to find'

EMA will conduct high-speed flybys of six asteroids before reaching and orbiting 269 Justitia. It will travel a total of about 3 billion miles (5 billion kilometers), which is equivalent to circling Earth roughly 125,000 times, said Najwa Aaraj, the CEO of the Technology Innovation Institute (TII) in Abu Dhabi, which designed, built and tested the mission's lander.

Along the way, the MBR Explorer will utilize gravity assists from Venus and then Earth to swing deeper into space, zipping past its first three asteroid targets: 10253 Westerwald, 623 Chimaera and 13294 Rockox. A subsequent gravity assist from Mars will fling the spacecraft even farther out, guiding it past three more space rocks: 88055 Ghaf, 23871 Ousha and 59980 Moza.

By 2036, the spacecraft is scheduled to rendezvous with its final and most intriguing target, 269 Justitia. A roughly 30-mile-wide (50 km) object in the middle of the asteroid belt, 269 Justitia is unusual for its remarkably crimson hue.

Its distinct color more closely resembles icy objects in the Kuiper Belt beyond Neptune than its immediate main-belt neighbors. This unique trait has led planetary scientists to hypothesize that the asteroid formed in the frigid outer solar system and migrated inward early in the solar system's history. If true, visiting 269 Justitia would offer a rare, close-up look at pristine material from the distant outer solar system via a much shorter journey.

Scientists are particularly excited that the asteroid may still hold water-related minerals and organic compounds preserved from its origins. Studying its surface could therefore offer clues to how water and organic material were distributed as planets began to form, Elias Tsoutsanis, a chief researcher at TII's propulsion and space research center, said during the press briefing.

"We don't know what we're going to find — that's exploration," Tsoutsanis told reporters. "We're really excited."

According to the mission plan, the MBR Explorer will spend roughly seven months studying 269 Justitia from orbit. Beginning at an altitude of 155 miles (250 km), the spacecraft will gradually lower its path before releasing the lander. The smaller probe will then head toward the asteroid's surface, a descent that should take two to three hours depending on 269 Justitia's precise gravity, which remains unknown.

Although TII describes the mission ending with a landing on the surface of 269 Justitia, the engineering details suggest a more violent endgame. Cruising toward the asteroid's surface at 15 to 27 meters per second (34 to 60 mph) with no meaningful way to slow down, the probe will function less like a traditional lander and more like a planned impactor.

"We don't expect that the probe will survive the touchdown," said Mariam Alhammadi, a researcher in TII leading the mission's electric propulsion.

To ensure its two onboard cameras capture essential imagery during the descent, the probe will rely on an attitude-control system to counteract any post-separation spin, Alhammadi said. Should the probe unexpectedly survive the hard landing, she added, its battery is built to last 20 to 50 minutes, providing a narrow but crucial window for it to beam close-ups of the asteroid's surface back to Earth.

The high-velocity impact is also expected to dig a small crater on 269 Justitia, possibly exposing pristine subsurface material. Because this material cannot be imaged from orbit, the team expects the probe's final images to be among the most valuable of the entire mission.

Zero margin for error

Back on Earth, the team faces an unforgiving timeline. To execute the planned flybys, the mission must launch during a narrow three-week window that opens in early March 2028.

"God forbid we miss that — we basically don't have a mission," Mohsen al-Awadhi, the mission director at the UAE Space Agency, told reporters at the press conference. The orbital mechanics are so rigid that another comparable opportunity will not arise for at least 100 years, prompting al-Awadhi to add that he is devoting no time and energy to a backup plan.

Meeting the launch window is just the first hurdle, however. Once deployed in deep space, the lander must operate with absolute autonomy, receiving no commands from Earth or the main MBR Explorer spacecraft, the team says.

"In these eight years, I have no control to call it back — so nothing can go wrong," said Aaraj.

The team is confident that rigorous engineering and testing have produced a probe that can essentially "think for itself." Equipped with AI, it is designed to decide on its own when to capture images and how to filter and rank the most valuable data. Rather than waiting until it reaches its destination, the lander will take images throughout its eight-year cruise and send the best ones back to Earth roughly every six months, according to a TII statement.

Officials declined to disclose the mission's overall cost or say whether it has stayed on budget. The United States' ongoing war in Iran has sparked missile and drone attacks across the UAE, but the mission team has persevered: WIRED reported that they pressed on even as missiles were intercepted overhead.

Looking ahead

Beyond the immediate scientific return, officials said a central pillar of this mission is accelerating the UAE's sovereign deep-space capabilities and fostering its domestic space economy.

The UAE Space Agency, established in 2014, has steadily expanded its portfolio from satellite launches to a Martian orbiter and sending two astronauts to the International Space Station. The EMA probe represents a developmental leap, designed and built in just under two years by a team of roughly 50 local engineers and scientists, many of whom began their careers as entry-level technicians on the Hope Mars mission.

"I don't want to call them my kids — there's a lot of them — but that's how attached I feel to them," al-Awadhi said during the briefing.

The UAE aims to position itself among the world's 10 largest space economies by 2031, targeting a massive expansion of a sector currently valued at about $12 billion. According to al-Bannai, the EMA project is designed to be one of many programs to come. By the time the lander impacts 269 Justitia in 2036, the technology matured during this journey will already be driving the next generation of Emirati spacecraft, he said.

"That's the journey we're on today."

An ancient crater buried underneath the Oklahoma town of Ames has been discovered to be almost 100 million years younger than thought, consequently connecting it to one of the big five mass extinction events in Earth's history.

The crater, which spans about 10 miles (16 kilometers) in diameter, is buried under 9,000 feet (2.7 kilometers) of sedimentary rock and was not discovered until seismic readings revealed it in 1991.

Initial estimates of the crater's age came from the discovery of the tooth in a rock found within the impact site. It was identified as belonging to an ancient eel-like creature called a conodont, which existed during the middle of a geological period known as the Ordovician, in a rock found within the impact site. This period was marked by a dramatic bombardment of asteroids known as the Ordovician Meteor Event 467.5 million years ago, which left nearly two-dozen craters spread around the world, all within 30 degrees of the equator. This equatorial pattern suggests there may have been a ring of material from a broken-up asteroid encircling the Earth's equator.

However, a team led by Elizabeth Catlos of the University of Texas at Austin has arrived at a different conclusion, finding that the crater is 370 million years old instead. So rather than being part of the Ordovician Meteor Event, this new dating places it around the time of the Late Devonian mass extinction, also referred to as the Frasnian–Famennian boundary extinction.

"With this research, we're basically taking a major pawn out of the Ordovician Meteor Event and dumping it into the Frasnian–Famennian event and saying, 'this is where this impact belongs'," said Catlos in a statement.

The new evidence for the age of the Ames crater comes from zircon crystals. Zircon is a silicate mineral, and zircon crystals can be dated by analyzing the amount of uranium and lead contained within them. When zircon crystals form they contain uranium and thorium, but the formation process pushes out lead atoms. A newly formed zircon crystal therefore contains no lead, but over time uranium radioisotopes decay into lead atoms, so the more lead a zircon crystal contains, the older it is.

The pressure of the impact that gouged out the Ames crater would have formed new zircons. Working with a team at NASA's Johnson Space Center, Catlos' group were able to image the zircon crystals using cathodoluminescence and electron backscatter diffraction. Cathodoluminescence bombards materials with electrons, which causes materials to emit photons at different wavelengths depending upon the material's composition. Electron backscatter diffraction, on the other hand, is a technique that uses a scanning electron microscope to study how electrons are diffracted at different angles by different atoms.

"No matter what technique we used, it was coming back to this younger signal," said Catlos.

So what about the fossil conodont teeth? The teeth were probably in the rock a long time before the impact, and just got jumbled in the violence that formed the crater.

While the impact alone was not big enough to cause a mass extinction, it may have contributed. Other possible causes of the extinction include a reduction in oxygen, super-volcanism or a nearby supernova, or possibly all these events operating in tandem.

When the impact occurred 370 million years ago, what is now Oklahoma was submerged beneath a shallow sea, which is how the 1.6 miles (2.7 kilometers) of sedimentary rock that today covers the crater was laid down. The impact also fractured the Earth's crust beneath it, and these fractures have allowed oil and natural gas to seep up. Wells struck oil three kilometers down inside the crater and since 1991 it has produced 17.4 million barrels of oil and a volume of 79.5 billion cubic feet (2.25 billion cubic meters) of natural gas.

Danny Stockli, who is the Dean of the Jackson School of Geosciences at the University of Texas at Austin and a co-author of the research, is effusive in his praise of using zircon crystals to date the ages of craters.

"These small crystals allow us to go back in time and learn about the major changes to Earth's ancient landscapes," said Stockli. "It would be great to do this for more of the meteor impact sites across the continent so we could get a more accurate timeline for these major events."

The findings were published in July in the journal Meteoritics and Planetary Science.

The asteroid Bennu was shaped on the boundary between hot and cold in the dusty disk that formed the planets 4.5 billion years ago, meaning the samples brought back from this space rock by NASA's OSIRIS-REx mission give us our best look at the primordial material from which the planets assembled.

"Bennu may offer our best glimpse of the original mix of chemical elements from which the terrestrial planets were ultimately built," said Maria Schönbächler, a professor of isotope geochemistry at ETH Zurich in Switzerland, in a statement.

Bennu is a near-Earth asteroid that NASA visited with its OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) mission between 2018 and 2021. Then, on Sept. 23, 2023, the OSIRIS-REx spacecraft which parachuted down to Earth a sample of 0.26 pounds (120 grams) of regolith from Bennu.

The material in that sample was subsequently shared out among researchers around the globe, including half a gram being received by Schönbächler's lab. The findings of Schönbächler and her team had subsequently changed what we thought we knew about the birth of Bennu.

They analyzed isotopes — variations of elements with greater or lesser numbers of neutrons — of iron, titanium and chromium in the sample, finding iron and titanium in particular to be well mixed throughout. Bennu's composition is also remarkably similar to another asteroid, Ryugu, from which Japan's Hayabusa2 mission has also obtained a sample. A rare breed of meteorite, called CI chondrites, also share a similar isotopic composition with Bennu and Ryugu, suggesting a common birthplace.

And that's where things get really interesting. Both Bennu and Ryugu are pieces of larger bodies that at some point were smashed apart. Some scientists have suggested that those parent bodies probably formed far from the sun in the outer solar system, maybe even alongside comets, and that they formed later than the planets since processes that far out are relatively slow.

However, the isotopic analysis of the Bennu sample by Schönbächler's team begs to differ. The even mixing of the isotopes suggests that it was formed from fine dust grains rather than clumpy, coarser material. The presence of water molecules also implies it formed closer to the sun than had been thought.

Schönbächler's team posit the following scenario: that Bennu formed close to the snow line, which was the dividing line in the planet forming disk beyond which temperatures were too cold for water vapour, the water instead froze as ice. Inside the snow line the temperatures were hotter, causing ice to sublimate into a gas or melt into a liquid. This snow line between fire and ice existed roughly where Jupiter does today. Material from both sides of this line flowed together to assemble the parent objects of Bennu, Ryugu and CI chondrites, with ice acting like glue to bond the fine dust particles together.

And Jupiter had a role to play in this process too. The giant planet formed fairly soon after the sun (within a million years). As it grew and came to dominate its orbit, it acted as an obstacle to heavier, coarser clumps of dust while finer grained dust was able to flow around it and feed into the zone where Bennu formed. This explains why the isotopes are so well mixed rather than clumped, and also tells us that Bennu's parent probably formed not long after Jupiter did. The prevalence of water-bearing minerals in the Bennu sample also suggests that water-ice that sublimated into vapor just inside the snow line was also part of the material that was transported into the region where Bennu and its cousins were built.

"Bennu is a hybrid," said Schönbächler. "The material does not clearly match either the inner or the outer solar system." Instead, Bennu has characteristics derived from both regions.

What's more, the well-mixed fine-grained material more closely matches the composition of the pre-solar nebula and hence the sun itself. This means that Bennu is stuffed full of primordial material that was the foundation for the formation of the solar system, and can help us better understand the material out of which the planets, including our Earth, came to be.

What's intriguing is that both near-Earth asteroids, Bennu and Ryugu, which have been destinations for successful sample-return missions should both have very similar origins. Is that pure coincidence, or is it telling us something about where the population of near-Earth asteroids came from?

"We are now wondering whether other asteroids have the same isotopic signature as Bennu and Ryugu," said Schönbächler.

The only way that can be answered is by going and obtaining more samples. A Chinese mission called Tianwen-2 arrived this summer at the near-Earth asteroid Kamo'oalewa, to bring back a sample next year, while Japan's Martian Moons eXploration mission, set to launch this August, plans to bring back a sample from Phobos in 2031. While designated a moon of Mars, Phobos is thought to possibly be a captured asteroid. If so, its isotopic composition might have more in common with Bennu than with Mars.

The latest findings from Bennu were published on Sept. 23 in the journal Science Advances.

It may not be a slime creature from outer space, but you can finally find "Weird Al" Yankovic's name flying beyond our planet.

The American musician and comedian's name was recently approved for an asteroid, or space rock, that zooms around our solar system about once every four years.

The asteroid is formally known as (14331) Alyankovic, or 1981 EC26. 1981 refers to the year of the asteroid's discovery, and Yankovic's name for it was approved by the International Astronomical Union (IAU), the official body that arbitrates the monikers of things in the universe.

Planetary scientist Allison McGraw, an alumna of the University of Arizona who is now with the Lunar and Planetary Science Institute, backed the nomination with several other planetary science researchers, according to the Tucson Star. On Sunday (Sept. 20), McGraw presented Yankovic backstage with a plaque commemorating the naming of the asteroid, ahead of Yankovic's performance at the Tucson Arena.

"I've been working on not being starstruck, the same way I am every time I meet astronauts," McGraw said in the Tucson Star's report, ahead of the meeting. "I'm gonna do my best not to be starstruck, or I guess 'rock struck', but I have the feeling that he's going to be really cool."

Alyankovic (the asteroid) was discovered in 1981 and resides in the main belt of asteroids found between Mars and Jupiter. It is visible from Earth, but only in a good telescope as its absolute magnitude is 16; for comparison, the faintest stars visible to the naked eye are roughly magnitude 5 or 6, under dark-sky conditions.

Alyankovic joins several other musical-themed celebrity monikers on asteroids, such as 17059 Elvis, 17473 Freddiemercury, 249516 Aretha (after Aretha Franklin), 10731 Dollyparton, and all members of the Beatles (both individually, and as a group for 8749 Beatles.)

Meanwhile, Al Yankovic (the singer) has been belting out funny space-related tunes for decades, including the rap-like "Sir Isaac Newton vs. Bill Nye", an Obi-Wan Kenobi-centered retelling of Star Wars: The Phantom Menace called "The Saga Begins," and the self-explanatory and classic "Attack of the Radioactive Hamsters from a Planet Near Mars."

While living persons can have their names attached to asteroids and other "small bodies" like comets, the process can take years, and any name must meet a multi-page set of requirements as well as the muster of the IAU's working group that names small bodies.

"Names have traditionally been assigned to many small bodies and have drawn from mythological characters, planetary scientists, astronomers, and accomplished scientists, engineers, and technicians in other fields. People who have made contributions to the arts, sports, medicine, and other aspects of society are also recognized. Discoverers have also used names of personal significance to them," the IAU states.

Some of the other institutions or things named in the Sept. 9 IAU notice include:

• (15708) Metsoc = 1988 RB12. It is named for the Meteoritical Society, which has an annual conference and hosts the Meteoritics and Planetary Science journal, in large part to showcase countries that are not as widely represented.
• (20176) Aliciagoyena = 1996 XK29. This is named after Alicia Goyena, an educator and history teacher in Uruguay who was director of the women's section of the Instituto Batlle y Ordóñez in Montevideo.
• (31550) Beckmaier = 1999 DT7. Beck Maier is a telescope operator at the Lowell Observatory's Lowell Discovery Telescope in Arizona.
• (50271) Albertoanunziato = 2000 CW. Alberto Anunziato is an Argentinian amateur astronomer whose work includes founding the Argentine Lunar Society, being secretary of the Ibero-American Astronomy League, and teaching at the Autonomous University of Entre Ríos.
• (74025) Marquette = 1998 HA6. Jean-Baptiste Marquette is a retired French astrophysicist known for mapping the chemistry of interstellar clouds.

AstroForge plans to make spaceflight history next year.

The California-based asteroid-mining company has booked its Autonomy-1 mission on the first-ever flight of Stoke Space's Nova Pathfinder rocket, which is scheduled to launch in early 2027. As its name suggests, Autonomy-1 will operate independently, thanks to AstroForge's newly developed Solo spacecraft intelligence model.

"Autonomy-1 will be the first space mission to complete its entire mission after separation without a single command from the ground," AstroForge CEO and co-founder Matt Gialich wrote in a Tuesday (Sept. 22) blog post announcing the mission. "Using Solo, we will remove the human operator from the loop."

AstroForge was founded in January 2022 with an ambitious goal in mind, which the blog post states: "to unlock the resources of the solar system."

AstroForge will go after metals, which it plans to extract using a fleet of spacecraft spread throughout the final frontier. Manually controlling a large number of such probes would be a taxing and expensive enterprise, which explains why the startup developed Solo.

The intelligence model is "designed to autonomously coordinate a spacecraft's onboard functions," Gialich wrote in the blog post. "Solo works on top of AstroForge's existing deterministic, physics-based flight software, allowing the spacecraft to make decisions in real time during flight."

Achieving full mission autonomy is the "holy grail of spacecraft engineering," he added. And AstroForge will tackle it in a stepwise fashion.

Solo will first fly on the DeepSpace-2 mission, which will launch on the same SpaceX Falcon 9 rocket slated to send Intuitive Machines' third robotic lunar lander toward the moon later this year.

DeepSpace-2 aims to rendezvous with a near-Earth asteroid, but Solo won't coordinate any of those operations. Rather, the intelligence model will act in "shadow mode," meaning it will process spacecraft data and make decisions, but those decisions will not be implemented.

Things will change on Autonomy-1, which will be a full-scale demonstration of Solo in Earth orbit.

"The mission objective is deliberately straightforward: after Autonomy-1 separates from its launch vehicle, we do not intend to send the spacecraft a single command," Gialich wrote.

"Autonomy-1 will transmit telemetry and science data back to Earth so that we can observe what the spacecraft is doing, understand the decisions Solo makes and collect science," he added. "But that information will only flow one way — from the spacecraft to the ground."

Solo will also have to support the activities of a scientific payload — those of COMPASS (Compact Multi-Spectral Photometer for Space Science), a NASA heliophysics instrument that's flying on the mission.

AstroForge already has two space missions under its belt. The company sent a prototype cubesat called Brokkr-1 to Earth orbit in April 2023, but was unable to activate its refinery tech.

Then, in February 2025, AstroForge's Odin spacecraft launched to deep space along with Intuitive Machine's IM-2 moon-landing mission. Odin was supposed to fly by and study a near-Earth asteroid, but AstroForge had trouble establishing communications with the spacecraft, which ended up being lost.

Autonomy-1's launch will be closely watched, and not just by people who care about asteroid mining. It will be the first-ever orbital launch for Stoke Space, a company developing fully reusable rockets — tech that experts say could revolutionize spaceflight. One such believer is SpaceX, which is developing a fully reusable vehicle of its own — the Starship megarocket.

Studying 75 meteorites falling to Earth, scientists have identified the seven stages a space rock goes through as it crashes through our atmosphere, each of which is determined by different physical processes.

The research found that there are more factors than mere evaporation that determine how fragments of asteroids and comets lose mass and speed passing through the atmosphere before slamming into the ground as meteorites. As well as just "burning up" in the atmosphere, space rocks also go through periods of melting and fragmentation that occur at different altitudes.

Aside from shining light on the life cycles of meteorites, the team's research could help us better understand what would happen if a large, potentially hazardous asteroid were to enter Earth's atmosphere.

"We used to think that solid rocks would evaporate from the enormous heat and brilliant light generated in the air collision," team leader Peter Jenniskens of the SETI Institute and NASA Ames Research Center said in a statement. "We found instead that first melting and then fragmentation control how a rock loses mass."

Seven stages to Earthfall

The first stage, phase 1, identified by the team, begins high in Earth's atmosphere. The falling space rock creates a shock wave in front of it that heats it and the gas surrounding it. This turns the falling space rock into a "shooting star" streaking across the sky.

Phase 2 begins when the fragment reaches denser air, and the meteor begins to brighten. At this stage, astronomers can determine how the rock is spinning based upon changes in brightness.

This brightening continues until phase 3, at which point the space rock becomes a fireball. The team found that it is at this stage that the falling rock loses the most mass via melting. This happens as air flows rapidly around the rock and pulls away melted matter, leaving a trail of droplets that continue to evaporate.

At around 40 miles (60 kilometers) over the surface of Earth phase 4 begins, which sees the fireball reaching a melting equilibrium. By this point, the initial space rock may have lost up to 40% of its original mass.

Phase 5 marks the point at which the rock starts to fragment, with individual pieces often flaring as they break away from the main body. The team found that this breaking apart often occurs earlier than expected, putting that down to cracks that may have already existed in the rock due to collisions in space.

What remains of the rock by this stage shrinks rapidly, also slowing significantly, with this slowdown occurring faster if the rock has fragmented more successfully.

"Our modeling shows that as long as the back of the space rock remains intact, that rock pulls a vacuum in its wake into which fragments tend to flow," team member Darrel Robertson of NASA Ames Research Center said. "Those small meteorites fall in a narrow strip on the ground."

The fireball flares for the final time during phase 6, as pieces of the space rock break away more rapidly.

"That final disruption sends fragments flying at higher relative speeds," said Jenniskens. "In past falls, we noticed that meteorites larger than about 20 grams tended to be scattered wider, and many came from close to the surface of the original space rock, which must have been its backside."

At the start of phase 7, melting and fragmentation are still occurring, but what is left of the space rock has slowed down enough to stop glowing. Melting then ceases, leaving a thin crust on the surface of the fragment.

The team determined that meteorites that reach terra firma ironically went through more melting and fragmentation, which slowed them down enought to actually land. The fragments are often small and slow enough at this stage to allow Earth's winds to carry them off course and determine where they land as meteorites.

Of the 75 meteorites investigated in this research, the team identified several different types of space rock composed of different materials. They were able to determine the altitudes at which these different types of space rock went through each of the seven identified phases.

Identifying the processes that occur to solid objects passing through the atmosphere could help scientists better understand what would happen to larger, more dangerous objects about to hit Earth. This includes objects that cause damage when they erupt as "airbursts" or potential "planet-killer" asteroids the size of city blocks.

"Asteroids up to tens of meters in size are also solid rocks because they tend to spin faster than do the larger rubble pile asteroids," said Jenniskens. "The 20-meter [66 feet] diameter asteroid that caused the airburst over Chelyabinsk, Russia, in 2013 went through the same phases."

The team's findings appear in a paper published on the Wiley Online Library.

On Aug. 28, 1993, NASA's Galileo spacecraft flew by the asteroid Ida while on its way to Jupiter.

Galileo was the first spacecraft to fly by an asteroid in the asteroid belt. Ida was actually the second one it visited after another flyby of the asteroid Gaspra in 1991.

Galileo whizzed by asteroid Ida going almost 28,000 mph and came within 1,500 miles of the asteroid's surface. During the encounter, Galileo actually discovered a tiny moon orbiting Ida! This was the first confirmed satellite of an asteroid. The International Astronomical Union named the moon Dactyl after a group of mythological beings who lived on a sacred mountain called Mount Ida.

Why it mattered

Asteroid 243 Ida was actually the second asteroid ever to be visited by a spacecraft (Galileo previously flew by the asteroid Gaspra in October 1991), but this flyby clinched the theory that asteroids could have moons.

Until the Galileo spacecraft photographed Ida and Dactyl, astronomers suspected some asteroids could have their own moons, but Galileo proved it once and for all. During the flyby, Galileo approached within 1,500 miles (2,400 kilometers) of Ida as it made its way to Jupiter.

• The greatest asteroid missions of all time!

"It was previously thought that natural satellites of asteroids could form, but they probably weren't common," Torrence Johnson, Galileo's project scientist, once said of the flyby in a NASA statement. "Having found one fairly quickly, we can say that they're probably more common than previously thought."

Ida is an S-type asteroid made mostly of silicate rock and sits in the main asteroid belt. Astronomers suspect it is what's known as a Koronis asteroid, leftover debris from an ancient crash of two much larger objects, according to NASA. It was discovered on Sept. 29, 1884 by Austrian astronomer Johann Palisa at the Vienna Observatory.

Galileo imaging team member Ann Harch actually discovered Ida's moon Dactyl on Feb. 17, 1994, months after the flyby, while reviewing data, NASA said.

Galileo did not stop to study Ida and Dactyl. As with its Gaspra flyby, the probe zoomed by to continue its trip to Jupiter. NASA launched the Galileo mission on Oct. 18, 1989 and it arrived at Jupiter on Dec. 7, 1995, orbiting the giant planet for nearly 8 years. The mission ended on Sept. 21, 2003, when Galileo intentionally crashed into Jupiter.

Want more space history? Check out our full On This Day In Space Story archive and watch our On This Day In Space videos on YouTube.

New images reveal what astronomers believe is the first-known "trilobate" or three-headed asteroid in our solar system.

What is it?

These new images capture the asteroid known as (44) Nysa, or just Nysa, as it spins through the main asteroid belt located between Mars and Jupiter. The images were captured with the Very Large Telescope in Chile and the Large Binocular Telescope in Arizona.

Nysa was first observed in 1857, but it wasn't until the new images were captured when scientists were able to resolve its unique three-headed structure. The asteroid appears to be around 47 miles (75 kilometers) in circumference at its widest point, with two narrow "necks" that give it its odd "trilobate" shape.

Even more incredible, astronomers were also able to resolve that a 0.6-mile-wide (1-km-wide) moon seems to orbit Nysa. The tiny moon, currently known as S/2026 (44) 1, appears to orbit the asteroid at a distance of around 106 miles (170 km).

Why is it incredible?

Astronomers say these images reveal (44) Nysa to be unlike any other asteroid we've seen in our neck of the cosmic woods.

"The images reveal a remarkably unusual object," said Kate Minker of Arizona's Lowell Observatory in a statement announcing the discovery. "The most likely explanation is that Nysa is either a contact trinary, consisting of three connected components, or an extremely irregular coherent body unlike anything we've previously observed."

Scientists can study asteroids like Nysa to learn about how the planets of our solar system formed. Nysa belongs to a class of asteroids believed to have formed closer to the inner solar system and therefore may have a similar composition to the building blocks that would go on to form the inner planets.

Scientists once suspected that a brutal, years-long winter starved the dinosaurs following an asteroid impact 66 million years ago. New evidence suggests a more violent end: widespread firestorms that may have burned even thick-skinned dinosaurs to a crisp within hours.

The roughly six-mile-wide (10-kilometer-wide) asteroid struck Mexico's Yucatán Peninsula, excavating the Chicxulub crater and vaporizing enormous quantities of rock. Some of that material condensed into tiny droplets called spherules, which spread around the planet before falling back through Earth's atmosphere at several miles per second.

As the spherules slowed, their kinetic energy became heat, producing an intense pulse of thermal radiation. Earlier models suggested the effect would have resembled a worldwide broiler that was potentially deadly to exposed, thin-skinned animals, but not powerful enough to ignite vegetation across the globe.

A new study argues that those calculations overlooked a crucial ingredient: a thick layer of fine silicate dust formed from rock vapor that did not initially condense into spherules. Evidence for that dust emerged in 2023 from the Tanis fossil site in North Dakota, where researchers identified a layer of extremely fine, impact-derived material deposited above the spherules. A similar dust layer has since been documented at the K–Pg boundary (which divides the "age of reptiles" and the "age of mammals") in Raton Basin across the Colorado–New Mexico border.

"It reinvigorated my interest in what happened to the leftover vapor — that's where this work started," lead author Brandon Johnson, a planetary scientist at Purdue University, said in a statement.

The dust would have acted like an insulating blanket, preventing thermal radiation from escaping into space and redirecting more heat toward Earth’s surface. The researchers estimated that the surface heat pulse could have been about 3.5 times more intense than what was suggested by models considering the falling spherules alone. "We're in the realm where we might be essentially killing off everything within that first hour or two," Johnson said.

The radiation may not have directly ignited thick pieces of wood, but it exceeded ignition thresholds for grass, lichen, and pine needles, which could have fueled larger fires. The study also found that exposed terrestrial animals may have received about 17 times the thermal dose considered lethal to humans.

Animals sheltering underground or in water would have had a better chance of surviving the initial heat pulse. Afterward, the same dust may have blocked sunlight for years, triggering the prolonged "impact winter" more typically blamed for the dinosaurs' extinction.

There is, however, a missing element: the wildfire evidence that supports this dust-caused inferno theory has only been found in North America. "It could be that we will eventually find the record of completely global wildfires," said Alfio Alessandro Chiarenza, a paleontologist at University College London who was not involved in the study. "We just don't have it so far."

The study was published on July 28 in the journal JGR Biogeosciences.

Scientists have found the first triple-lobed asteroid in the asteroid belt between Mars and Jupiter — and it has a small moon to boot.

The asteroid in question is 44 Nysa, which was discovered all the way back in 1857. Of course, back then it was just a pinprick of light in the sky, and subsequent observations — including some from the Hubble Space Telescope — had failed to tell us much about Nysa. Those previous observations suggested Nysa might be bi-lobed, like many asteroids and comets such as asteroid 52246 Donaldjohanson, which NASA's Lucy mission flew past in 2025.

However, new joint observations by the Large Binocular Telescope (LBT) on Mount Graham in Arizona and the Very Large Telescope (VT) on Paranal mountain in Chile have revealed that this asteroid actually seems to have three lobes, the first such object ever seen.

"The images reveal a remarkably unusual object," said lead researcher Kate Minker of Arizona's Lowell Observatory in a statement. "The most likely explanation is that Nysa is either a contact trinary, consisting of three connected components, or an extremely irregular coherent body unlike anything we've previously observed."

Obtaining the detailed images of Nysa was not easy. Key to the success were two high contrast imaging devices, the Italian-built SHARK-VIS on the LBT and SPHERE and its ZIMPOL polarimeter on the VLT, used in conjunction with adaptive optics that counteract the blurring effect of the atmosphere.

"These observations had to be combined with specially developed image-processing techniques to further sharpen the images and remove the bright halo surrounding the asteroid, potentially hiding faint companions," said Anthony Berdeu of the European Southern Observatory.

The images showed an irregular-shaped body 47 miles (75 kilometers) at its widest point, with two notable valleys or "colli" that wrap around the asteroid's circumference and which Minker's team interprets as being the necks of the different lobes. Furthermore, the images revealed a 0.6-mile-wide (1-km-wide) moon orbiting Nysa at a distance of at least 106 miles (170 km). The moon has been designated S/2026 (44) 1 for now. And, because it was seen independently during two different observing campaigns, it was possible to observe its motion around Nysa.

"We borrowed a specialized technique from another field of astronomy, known as high-contrast imaging, to detect the small moon whose faint light was overwhelmed by the intense brightness of the primary asteroid," said Gianluca Li Causi of the SHARK-VIS team at the Italian National Institute for Astrophysics (INAF).

Nysa is named after the mythical land where the ancient Greek god Dionysus was raised by nymphs. Al Conrad of the Large Binocular Telescope Observatory finds the name fitting because Dionysus was the Greek god of theater, which for the ancient Greeks often involved wearing masks and hiding one's true identity.

"We're finally unmasking the asteroid's true nature, long after it was discovered," said Conrad.

How such a bizarre object formed remains uncertain, but Minker's team does have a couple of ideas.

The team's preferred explanation is that Nysa is a contact trinary — three asteroid bodies being held together loosely by gravity. The best alternative, the researchers say, is that Nysa once upon a time had a close encounter with a much larger asteroid that slammed into it, thereby deforming it. In these situations, modeling suggests that gravitational tidal forces could have deformed Nysa's mantle, creating Nysa's odd shape and even ripping it apart into a bunch of fragments in a string-of-peals configuration. If this is the case, then where did the other fragments go? Such events usually produce a family of asteroids all sharing the same composition, but Nysa seems to be alone (barring its moon, of course).

There could be a way to distinguish between the two possible origins. By tracking the moon's orbital velocity and period, astronomers will be able to pin down the exact mass and density of Nysa and then see which model matches it best.

Nysa has been a subject of study because it can also tell us about the birth of our own planet Earth. Nysa is more reflective than many other asteroids thanks to its surface composition that is abundant in a silicate mineral called enstatite, which lacks iron. Asteroids like this are generally called E-types, and Nysa is the largest and brightest of all of them. E-type asteroids are thought to have formed close to the sun and therefore have been identified as potential building blocks of the inner planets. If Nysa is a relic of that time, it could tell us a great deal about conditions in the inner solar system 4.5 billion years ago.

The findings can be read on the arXiv archive, and have been submitted to the journal Astronomy & Astrophysics.

A near-Earth object that astronomers believed was an asteroid for nearly three decades has been unmasked as a faint, active comet, revealing a case of cosmic mistaken identity that could help improve planetary defense.

The object, known since its discovery in 1998 as 1998 SH2, appeared to be an ordinary asteroid. It follows a 4.5-year orbit around the sun and showed no obvious signs of cometary activity, such as the glowing coma or tail produced when sunlight vaporizes surface ice.

However, during a close pass about 2 million miles (3 million kilometers) from Earth in August 2025, researchers using NASA's Deep Space Network planetary radar system noticed something unexpected: The object wasn't where orbital predictions said it should be, according to a statement from the space agency. That discrepancy prompted scientists to take a closer look, and what they found surprised them.

Using decades of precision optical astrometry — measurements of the object's position against background stars — researchers found that gravity alone couldn't explain its irregular motion. Instead, they detected tiny nongravitational forces consistent with jets of gas escaping from the object's surface as hidden ice warmed in sunlight.

"After we measured the nongravitational perturbations affecting the motion of 1998 SH2 and recognized they weren't compatible with the object being an asteroid, we suspected the object could be an active comet," Davide Farnocchia, lead author of the study and navigation engineer with NASA's Center for Near-Earth Object Studies at the Jet Propulsion Laboratory, said in the statement.

To test the idea, the team observed the object with the European Southern Observatory's Very Large Telescope in Chile and the Canada-France-Hawaii Telescope atop Mauna Kea. The observations revealed a faint but unmistakable comet tail, confirming the object's true identity.

The discovery earned 1998 SH2 a second designation: P/1998 SH2, officially recognizing it as a comet. Beyond solving the mystery, the finding has important implications for planetary defense.

Unlike rocky asteroids, comets can subtly change course as gas escaping from their surfaces acts like tiny thrusters. Identifying those nongravitational forces allows scientists to more accurately predict an object's future orbit and assess any potential impact risk.

"This work shows the importance of continuously tracking near-Earth objects," Farnocchia said in the statement. "Because of outgassing, the motion of comets is more significantly perturbed than that of asteroids.

"Detecting these perturbations can be an important diagnostic tool for planetary defense that will help understand which objects may be comets rather than asteroids, how their orbits evolve, and how that influences their Earth impact risks."

The study also suggests that 1998 SH2 may not be unique. The researchers noted that analyzing the motions of near-Earth objects with increasingly precise astrometry could reveal more hidden comets that have long been classified as asteroids because they lack obvious tails or glowing comas.

As astronomers continue to monitor the growing population of near-Earth objects, subtle orbital changes may prove just as revealing as spectacular comet tails, uncovering more examples of cosmic mistaken identity while helping scientists better understand which objects pose potential threats to Earth.

Their findings were published July 10 in the journal Nature Astronomy.

China has announced that it wants to develop a "space-ground" asteroid early-warning network, while providing few details on what it could look like. But recent papers and presentations to the United Nations provide clues as to what the country has in mind for planetary defense.

The China National Space Administration (CNSA) made the announcement on June 30 — International Asteroid Day — stating plans to construct a coordinated ground-and-space monitoring system for near-Earth asteroids. Li Mingtao, chief scientist at CNSA's Asteroid Monitoring and Early Warning Research Center, told state media that China is studying the feasibility of an asteroid defense system, with the ground-space monitoring network as its core.

"No asteroid has so far been identified that will definitely collide with Earth in the foreseeable future, but concerns over impact risks are not unfounded. Many near-Earth asteroids remain undetected," the state-run media outlet Xinhua quoted Li as saying in a report by Science and Technology Daily.

Li added that China will deploy multiple large-aperture optical telescopes at carefully chosen sites in order to be able to survey the sky, while adding a space-based monitoring constellation, free from atmospheric disruption and day-night constraints, with a particular focus on threats from the sunward direction, which are, from the ground, lost in the glare of the sun. The meteor that exploded over Chelyabinsk, Russia, in 2013, approached roughly from a sunward direction and was only detected once it entered the atmosphere.

Li told Science and Technology Daily that more than 40,000 near-Earth asteroids have been discovered so far, including over 95% of asteroids at least 1 kilometer (0.6 miles) wide, which are capable of causing a globally catastrophic impact. However, only around 45% of asteroids in the 140-meter (460-foot) class have been detected, which are large enough to devastate a small country.

The June 30 reports and CNSA statements were vague on what China's actual plans for its monitoring network may be. However, recent journal papers and a 2025 presentation to the U.N.'s Committee on the Peaceful Uses of Outer Space (COPUOS) give more detail on the country's thinking.

For example, a paper published in the Journal of Deep Space Exploration in June 2026, co-authored by Wu Weiren, chief designer of China's lunar exploration program and a leading voice on the country's asteroid defense plans, lays out the options under study.

For the space-based component, the paper names four candidate orbital positions for a monitoring network: the Sun-Earth L1 Lagrange point, an Earth-leading or trailing orbit, a Venus-like heliocentric orbit, and an Earth-companion distant retrograde orbit (DRO). The paper also describes ongoing research into each option's monitoring effectiveness.

A similar outline was found in a 2025 technical presentation to COPUOS by Chinese researcher Chen Yongcai. A "basic model" would consist of a single satellite at Sun-Earth L1, an orbit about 1.5 million kilometers (930,000 miles) inside that of Earth, paired with northern and southern ground stations. An "extended model" includes spacecraft in the three additional orbits stated in the Wu Weiren paper. The Venus-like option in particular closely tracks an earlier proposal known as CROWN, a constellation of small satellites in Venus-like orbits designed to survey the sunward sky and use its favorable geometry to track other populations of near-Earth asteroids.

The status and timelines of these plans are unclear, but they do indicate a clear interest in and commitment to planetary defense by China. The country's 15th Five-Year Plan, approved in March, states that an asteroid defense engineering project is under study, while China is developing a kinetic-impact and observation demonstration mission, similar to NASA's DART mission and the European Space Agency's (ESA) follow-on Hera project, which is scheduled to launch in 2027.

While China's apparent plans are not unique, they could augment global efforts. Anne Virkki, an asteroid researcher at the University of Helsinki who's familiar with international monitoring efforts, noted that NASA and ESA have plans to send missions to Sun-Earth L1 to search for asteroids in infrared light — NEO Surveyor and NEOMIR respectively.

"If China launches a similar mission, hopefully it has some capability that the other two do not, and that it shares the data internationally and not only for Chinese scientists," Virkki said.

Virkki noted that asteroids approaching from the sun's direction aren't physically unusual, but they are simply harder to track, which statistically makes them more likely to produce a surprise. She also pointed to the persistent, less-discussed gap in radar tracking capacity. That capacity took a serious hit with the 2020 collapse of the Arecibo Observatory in Puerto Rico, with no U.S. successor in the works.

China has discussed building its own radar capability, which Virkki said would be a welcome addition, provided the data is shared openly. China has built the "China Compound Eye" or Fuyan project near Chongqing in the country's southwest, which can be used for near-Earth asteroid monitoring. Wu's paper also notes ground-based radar in the proposal for asteroid monitoring.

"Hopefully, as China's planetary defense plans become more specific, we'll see telescopes and space telescopes that complement the existing or planned capabilities of other countries, rather than repeat redundantly, and contribute data openly and collaboratively," Virkki said. She noted that there are likely about 100,000 near-Earth asteroids that could cause significant local damage if they hit Earth, and we know the orbits of less than half of all such space rocks.

2029 will mark the International Year of Planetary Defense, when the infamous asteroid Apophis will fly past the Earth just within the orbit of geostationary satellites. "There is a lot of work left to do, and international collaboration is crucial," said Virkki.

How do you stop a large, threatening asteroid on its way to Earth? A new Chinese paper, investigating the issue, suggests a "pre-excavation detonation" could be the solution if there's enough warning time.

There may be millions of asteroids in our solar system, with a tiny percentage of them posing a possible, very tiny threat to our planet. NASA and many other entities keep an eye on the skies, and continue discovering new asteroids, but have found no imminent threats yet; Apophis, previously believed to be a small threat during its 2068 flyby of Earth, has now been ruled out as a problem for the foreseeable future.

But Earth has been smacked by space rocks in the past, with even the moderate-sized Chelyabinsk incident of 2013 causing reported property damage near its blast site in Russia. And as the researchers of a new paper point out, asteroids tens of meters in size and larger have been tracked flying safely, but closely, by Earth.

Assuming a theoretical space rock is on an imminent collision course and exceeds about 330 feet (100 meters) in size, simply blasting it (or even guiding it away) may not be a viable option, the researchers said in a peer-reviewed study in the journal Space: Science and Technology.

"Traditional kinetic impact, or long‑term force deflection methods, offer limited energy and cannot achieve effective deflection within short timeframes," the researchers said in a press release, adding they found few comprehensive analyses of how to do so. (NASA did successfully deflect an asteroid moonlet's orbit with the DART spacecraft in 2022, for example, but that was a unique test case in space.)

So the team, led by Xiaowei Wang from the China Academy of Launch Vehicle Technology, instead proposed using one of two "defense modes" for large incoming asteroids.

The first mode is a more simple impact detonation — simply put, smacking the asteroid's surface to create a shallow crater, in which a nuclear device is exploded. The other mode is a "pre-excavation detonation", or using a penetration device to create a deeper crater before exploding a nuclear warhead to "achieve deep detonation" in the interior of the asteroid.

The researchers' modeling included the energy of a launch vehicle, the velocity of the impact spacecraft, and changes to the velocity of the asteroid, in each of these two modes. The two modes were also tested against a "virtual threat asteroid database" assuming warning times of anywhere between one year and 20 years.

All in all, assuming enough time is available, it seems the deep-crater method wins out. "The flyby pre-excavation detonation mode, due to its ability to autonomously select the cratering location and achieve deep detonation, offers stronger energy coupling," the researchers wrote in the press release.

Such an impact could "destroy" asteroids that are roughly 330 feet (100 meters) or of that range, and push away asteroids of a size reaching about 0.6 miles (1 km) by imparting a velocity change of roughly 1 m/s in about 60 days.

While a shallow-crater mission could be launched more quickly, the researchers added, "the impact location is random, energy coupling is weak, and requirements for the nuclear device's impact resistance and detonation timing are extremely stringent."

Real-world missions would also have to take into account the composition of an asteroid (as a pile of rubble would likely require a different approach than a solid rock), whether the pathways of any pieces generated by an impact pose a threat, and how to safely get the nuclear warhead into space in the first place, among many other technical issues. The researchers did not raise these considerations in the press release.

They did, however, provide "recommended solutions" for when to use each of the two options. The shallow impact might be preferable "for emergency defense" on a huge asteroid if there is an extremely short warning time, because that mission is less complex. Otherwise, the "deep impact" would be the way to go.

Three years before the skyscraper-size asteroid Apophis makes its very close (but safe) flyby of Earth, scientists have already begun charting exactly when and where billions of people can watch it sweep across the sky.

Speaking at an "Apophis T-3 Years" workshop held earlier this month at the University of Padua in Italy, retired cartographer Michael Zeiler and astronomer Rick Fienberg shared detailed visibility maps charting the asteroid's passage across Earth's skies.

According to their calculations, roughly 90% of the world's population — about 7.6 billion people — lives in regions where Apophis could, in principle, be seen with the naked eye on April 13, 2029. The actual viewing success will depend more on earthly considerations, however, including cloud cover and the extent of light pollution.

Known formally as 99942 Apophis, the space rock will not resemble a blazing meteor tearing through the sky. Instead, scientists say it will appear as a point-like speck of light gliding steadily across, which, at its closest approach, will appear to move by about the apparent width of the full moon every minute.

"It will definitely be noticeable," Fienberg told Space.com. "It's going to be moving more slowly than a satellite — it will cross the sky in hours, rather than minutes, and it will just be a point."

According to the new maps, the asteroid should remain visible to the naked eye for about seven hours, beginning over Australia at 11:00 a.m. EDT (15:00 UTC) and concluding over the North Atlantic at 6:00 p.m. EDT (22:00 UTC).

At 4:35 p.m. EDT (20:35 UTC), Apophis is expected to reach its greatest apparent brightness as it passes over Cameroon, offering prime viewing to an estimated 3.9 billion people across Africa, Asia, eastern South America and parts of Europe.

About an hour later, at 5:45 p.m. EDT (21:45 UTC), the asteroid will make its closest approach to Earth, passing about 19,700 miles (31,600 kilometers) above the North Atlantic — well inside the orbit of Earth's geostationary satellites. The event would be visible across much of South America, the United States, Africa and parts of Europe, reaching roughly 2 billion people.

"This is the first time we've been able to predict in human history an asteroid visibly passing by the Earth," Richard Binzel, a professor of planetary sciences at the Massachusetts Institute of Technology (MIT), said during the workshop. "That's part of a shared experience."

As excitement ramps up for the once-in-a-millennium spectacle, Binzel opened the workshop with three messages: "Apophis will safely pass the Earth. Apophis will safely pass the Earth. Apophis will safely pass the Earth."

That absolute certainty is the hard-won fruit of more than two decades of increasingly precise observations. When Apophis was discovered in 2004, early calculations suggested a 1-in-37 chance of an impact in 2029, making it the most potentially hazardous asteroid known at the time. Additional observations steadily refined the asteroid's orbit, eliminating any possibility of a collision in 2029 and also ruling out any impact threat for at least the next century, according to NASA.

With the impact threat removed, scientists now view the flyby as a rare opportunity to observe how Earth's gravity affects an asteroid during an exceptionally close encounter.

Our planet's gravity is expected to tug the asteroid into a new orbit around the sun without posing any future danger. During the flyby, however, those same gravitational forces may stretch and squeeze the asteroid enough to trigger landslides or expose pristine material hidden beneath its weathered surface. Or they may do almost nothing.

"We simply don't know what's going to happen," Binzel said during the workshop. "Apophis may go by and not care too much, or maybe we'll see something significant."

"That's why we have to look," he added. "We're gonna learn a lot either way."

At the workshop, scientists said they hope to monitor the flyby from observatories in Spain's Canary Islands, among other places, as its location in the Atlantic Ocean offers an ideal view of the asteroid's closest approach as well as favorable prospects for clear skies.

Japan's Hayabusa2 sample-return spacecraft is on target to make one of the closest ever flybys of a near-Earth asteroid in early July, as part of its extended mission campaign.

Hayabusa2 launched in December 2014 and rendezvoused with the asteroid Ryugu four years later. The spacecraft collected samples and delivered them to Earth in 2020, completing its primary objectives. But the hardy spacecraft still has bold plans to deliver new and exciting science data.

The spacecraft has been operating well, despite needing to briefly enter a protective safe mode last year, and now is set to make a flyby of the asteroid Torifune on July 5, Satoshi Tanaka of the Japanese Aerospace Exploration Agency (JAXA) said in a presentation on Hayabusa2 during the 35th Meeting of the NASA Small Bodies Assessment Group (SBAG) on June 11.

The flyby will see Hayabusa2 get within 1 to 10 kilometers (0.62 to 6.2 miles) of Torifune, using its instrument suite to study the roughly 450-meter-wide (1,476 feet) asteroid as it whizzes past at 5.3 kilometers per second (3.3 miles per second).

"This is one of the closest asteroid encounters ever attempted by a mission of this class," Tanaka said. "By combining advanced navigation techniques and the engineering capabilities of Hayabusa2, we have made it possible to achieve a flyby at a distance of only about 1 kilometer."

Torifune was first given the designation 2001 CC21 before being named for a deity from Japanese mythology. Tanaka says the asteroid is somewhat similar to Itokawa — the target of Japan's first Hayabusa mission — but little is known for sure about Torifune, adding a level of uncertainty to this extended mission objective.

"It's still a risky operation, because they had not planned for this," Patrick Michel, the principal investigator for the European Space Agency's Hera asteroid mission and part of the Hayabusa2 science team, told Space.com. "The second thing is that we have a high uncertainty on the size of the object," he added, with the dimensions of the asteroid unknown.

The asteroid could, for example, be a contact binary, according to Michel, in which two separate bodies came together at low velocities. Known contact binary small bodies include the Kuiper belt object Arrokoth, imaged by NASA's New Horizons, and comet 67P/Churyumov-Gerasimenko, described as a "rubber duck" when visited by ESA's Rosetta spacecraft.

"We're going to discover what it looks like. And each time we have seen a new asteroid, we've been surprised," Michel said. "We're going to discover another beast to put in the zoo of asteroids."

The very high velocity of the flyby means there will be limited time to collect images and other data on the asteroid, but the rapid encounter will also provide a useful test for planetary defense, as well as adding to planetary science.

The flyby, using advanced navigation techniques to guide and control the spacecraft, will be a useful test of a rapid reconnaissance concept that could be used to determine the physical properties of an asteroid. Such reconnaissance could provide vital information before intercepting a threatening asteroid with a kinetic impact, as demonstrated by NASA's DART mission in 2022.

Tanaka said that Hayabusa2 has been busy during its deep space cruise phase, including making observations of the zodiacal light and exoplanets, and the Torifune flyby will, hopefully, not be its final act. The ultimate goal of the Hayabusa2 extended mission is to visit the tiny asteroid 1998 KY26 in 2031, which would be the smallest asteroid ever visited. The spacecraft could even attempt to land on the miniscule world, which is just 11 meters (36 feet) wide.

The oldest known asteroid impact site on Earth was created 3.02 billion years ago in what's now Western Australia — not far from where we've seen the oldest traces of life on our planet.

A rock formation in Western Australia's Pilbara region seems to offer evidence of an asteroid slamming into Earth's newly-formed rocky crust around 3.02 billion years ago. That makes the formation, called the North Pole Dome, the oldest evidence of an asteroid impact on Earth, according to a recent study, which dated crystals in the rocks shocked and reshaped by the impact's tremendous heat and pressure.

It's the latest salvo in an ongoing debate about the age of the crater (or what's left of it after billions of years of erosion), and there's more at stake than bragging rights: a crater dating back this deep in Earth's distant past could shed light on the rise of the continents and the origin of life.

A rare glimpse

Inside most rocks in Earth's crust, tiny grains of mineral called zircon quietly record the passage of eons. Zircon contains tiny amounts of uranium, which slowly but steadily breaks down into lead; that steadiness is key, because the ratios of those two elements reveal how long it's been since a grain of zircon crystallized from hot, molten rock. In this case, zircon grains told Kirkland and his colleagues that it had been about 3.02 billion years since the tremendous heat and pressure of an asteroid impact melted zircon crystals in the rocks around North Pole Dome.

"Some zircons at the North Pole Dome have unusual branching, skeletal shapes," Kirkland said in an emailed press release. "We interpret these as impact-modified crystals, formed when older zircon was disrupted, partly recrystallized, and in places, regrown during the intense heating caused by the impact."

If Kirkland and his colleagues are right, the area, also called the Miralga Impact Structure, is the oldest trace of an asteroid colliding with our planet. The newly published date makes Miralga a relic of a tumultuous period in our solar system's history, called the Late Heavy Bombardment, when the giant planets were still jockeying for position in their orbits around the sun, flinging asteroids and comets toward the inner solar system in the process (or so cosmologists theorize). Amid this rain of space rocks, Earth was midway through the Archaean Eon, with the planet's surface finally cooling to form a thin crust of solid rock. Earth's surface lay beneath an orangish haze of methane, a little like a warmer version of Saturn's moon Titan.

And somewhere in there, the first life took shape.

The oldest traces of that early life are just a few kilometers from North Pole Dome: limestone stromatolites, made of layers of tiny sediment grains trapped in, and eventually left behind by, sheets of early bacteria. The ones in Pilbara are about 3.5 billion years old, another date courtesy of zircon grains. If the Miralga impact happened 3.02 billion years ago, it struck a world already teeming with overlapping mats of bacteria.

The oldest known Earth rock, a 4.35-billion-year-old sandstone formation (also dated using zircon), lies just a few hundred kilometers south of Pilbara, in the Jack Hills. Why is all of this — the oldest rocks, the oldest asteroid crater, and the oldest traces of life — in Western Australia? It's reasonably likely that crust formed, life emerged, and meteors smashed into the ground millions of years earlier, in places all over the world, but the evidence just happened to be preserved in this area of Australia. Most of Earth's very oldest rocks have long since been reworked by plate tectonics or erosion, basically erasing the first chapters of our geological record.

A heated debate about heated rock

"While the site had previously been identified as an ancient impact crater, its exact age remained uncertain," said Kirkland.

Last year, Kirkland and his colleagues proposed that the impact dated back to 3.47 billion years ago, almost the same age as the nearby stromatolites. In that same paper, the team suggested that the original crater – whose outline has long since eroded away, leaving behind only impact-shocked rocks and tantalizing hints – might have been up to 62 miles (100 km) wide. The 22-mile-wide (35-kilometer-wide) North Pole Dome itself seemed to mark the crater's center; rock in the middle of large craters often rebounds upward after the impact, leaving a peak or dome behind (picture the way the middle of a trampoline flexes upward, captured in a freeze frame).

But another group of geoscientists published a paper a few months later, arguing that Miralga (a name they gave the crater, based on the local Aboriginal peoples' name for the area) couldn't be any more than 2.7 billion years old, and only 10 miles (16 km) wide. That's still substantial, and old enough to be interesting, but too young and too small to have played much of a role in shaping the region's life, or its continental crust.

"By the time of the impact, the Pilbara was already quite old," wrote the study’s authors in an essay at the time (of the paper, not the impact).

The teams agreed on, basically, one thing: the area around North Pole Dome was definitely an impact site, and dating very old rocks is not easy. Both 2025 papers looked at the placement of rocks called shatter cones, which form when the shockwaves of an impact (or, sometimes, an underground nuclear bomb test) pass through rock, leaving behind ripples, striations, or cracks. But based on where the shatter cones appeared in relation to other rock layers, the two teams of scientists drew very different conclusions.

"Ancient craters are incredibly difficult to date, because over billions of years, rocks are altered by heat, pressure, and fluids, which can obscure or reset the original impact signatures," said Kirkland, whose team now argues that the zircon crystal dates are much more precise than either team's previous efforts. "What we've been able to do here is separate the moment of impact from its long geological history."

Curtin University geoscientist Chris Kirkland and his colleagues published their work in the journal Geology.

An asteroid now bears the name of beloved musician Elliott Smith, thanks to one ambitious filmmaker.

Elliott Smith passed away at the age of 34 in 2003, but his impact and his music continue to connect with people around the world. And his influence has now extended to space, thanks to independent filmmaker Orlando Campopiano, who worked to get an asteroid named "Elliottsmith."

"I hope this introduces at least one new person to Elliott's brilliant discography, and I'm happy to see a permanent legacy in the stars! To have this tribute to him blessed by the estate and discoverers is also a great honor," Campopiano told Stereogum.

While listening to the song "Shooting Star," from Smith's album "From a Basement on the Hill," which was released in 2004 following his death, Campopiano had the idea to try and get an asteroid named after Smith, he told Stereogum.

He took this inspiration and ran with it, connecting with Smith's estate and working together to submit a proposal to the International Astronomical Union (IAU), which gives official names to cosmic objects, including asteroids. Maybe there are some Elliott Smith fans at the IAU, because the organization actually said yes.

With this positive response, Asteroid (861969) 2014 OS439 is now officially "Elliottsmith."

The asteroid was discovered back in 2014 by the Pan-STARRS 1 (Panoramic Survey Telescope and Rapid Response System) project in Hawai'i.

The IAU's announcement of the renaming reads: "Steven Paul 'Elliott' Smith (1969–2003) was an influential, Oscar-nominated American songwriter. His intricate music left a lasting impact on many musicians. Asteroid 861969 honors his birth date, August 6, 1969. Smith often used celestial motifs in his work, notably in the song 'Shooting Star,' which, in hindsight, symbolizes his brief but brilliant light."

As this classification states, this asteroid is more than just a random rock in the sky. Its previous, numerical name 861969 happens to perfectly mirror Smith's birthday. This cosmic alignment makes it feel like this naming was truly meant to be.

You can get a look at the asteroid's place in our solar system on the small-body website of NASA's Jet Propulsion Laboratory, which you can find here.

Last year, NASA's Lucy spacecraft encountered a bi-lobed asteroid that is a chunk of an even larger rocky body that was smashed apart in an almighty collision 155 million years ago. This little pitstop happened on Lucy's way to a rendezvous with the Trojan asteroids that shadow Jupiter around the sun.

The asteroid 52246 Donaldjohanson, better known as "DJ" to Lucy's mission scientists and named after the paleoanthropologist who discovered the Lucy hominin fossil in Ethiopia in 1974, orbits the sun in the inner part of the main asteroid belt between Mars and Jupiter.

The true Lucy fossil dates back in time 3.2 million years and is an important link in the evolutionary chain that led to homo sapiens. Likewise, primitive asteroidal bodies are somewhat like fossilized remnants of the building blocks of the solar system's planets, including Earth. Understanding the make-up of these asteroids and where they formed versus where they are now can provide crucial insights into how Earth was assembled and where its organic materials and water may have come from.

Lucy flew past DJ in April of 2025. It is a pretty primitive asteroid, meaning that it has, or once upon a time had, certain volatile materials such as water-ice, as well as plenty of carbon — all things that can be removed thermally over time. Most objects that contain volatiles originate in the outer solar system, where it is cold enough that the volatiles do not sublimate away.

Within DJ's composition, Lucy detected iron-bearing phyllosilicates, which are a mineral formed in the presence of liquid water.

"Phyllosilicates are an indication that water was present and there was some degree of aqueous alteration," Simone Marchi, a planetary scientist from the South-west Research Institute and lead of the study into DJ, told Space.com.

However, for DJ to have had water, it must have formed further out from the sun, possibly in the outer asteroid belt.

"But DJ belongs to the inner asteroid belt so that's already intriguing," said Marchi.

The spectral evidence also indicates DJ was only partially altered by water, which Marchi says tells us something about its history.

"The aqueous alteration terminated early, and though we don't know why, we can speculate. In order to have aqueous alteration there needs to be some internal heating [usually via radioactive elements] and if something forms later than everything else then there will be less heat [since many of the radioactive elements will have already decayed]. Or perhaps there was just less water to start with where it formed."

What we do know is that DJ was once part of a much larger asteroid that suffered a giant impact 155 million years ago, causing the parent body to break apart into a number of chunks, the largest being the 45-mile-wide (73-kilometer-wide) asteroid 163 Erigone. Consequently, the remains of this parent asteroid, including DJ, are collectively referred to as the Erigone family.

DJ's violent origin may also explain its shape, which features two lobes joined together by a narrower and relatively smooth neck.

"We have now seen many small bodies in the solar system that appear to have this bi-lobed shape, and that's across a wide range of sizes," said Marchi.

For example the near-Earth asteroids 25142 Itokawa, which was visited by the first Japanese Hayabusa mission in 2005, and 4149 Toutatis that was encountered by China's Chang'e 2 in 2012, are both bi-lobed. So too is the tiny asteroid Selam, which is a satellite of the asteroid 152830 Dinkinesh visited by Lucy in 2023. Then there are cometary bodies including 67P Churyumov–Gerasimenko visited by the Rosetta mission and comet 19P/Borrelly, imaged by NASA's Deep Space 1 spacecraft in 1999.

These objects are all different sizes, different types and in different locations, but they all share the same structure. However, Marchi cautions that they might not all form the same way. For example, the neck between the lobes of comets such as 67P might form through erosion via sublimation and outgassing as the comet gets closer to the Sun, whereas for asteroids it might indicate a history of being involved in a giant impact, the resulting fragments coming together to be bound by gravity – a so-called contact binary.

Lucy now continues onwards, scheduled to encounter its first trojan asteroid, known as 3548 Eurybates, in August 2027. Trojans are asteroids that have been captured by Jupiter's gravity at the L3 and L4 Lagrange points, 60 degrees in front and 60 degrees behind Jupiter itself.

"We think that the Trojans, based on our understanding of the solar system, formed further out and then were captured where they are today following the early shuffling of the planets," said Marchi. "This shuffling could also have been the origin of DJ, so there could be a connection there between DJ and the Trojans."

Compositionally, the majority of trojans are expected to be even more primitive than DJ, containing more carbon, water and other volatile materials that would sublimate if they got too close to the sun.

That is all except one: Eurybates.

"It is the only one of our targets that from spectroscopy appears to be relatively similar to DJ. It's not identical, but it is closer in composition to DJ than the other Trojans, so it will be intriguing to compare them," said Marchi.

Indeed, any similarities will help tell us how asteroids were herded around during the first few hundred million years of solar system history following the formation of the planets. Jupiter and Saturn, especially, began migrating inwards and then out again. In doing so, their gravity pushed and pulled minor bodies all over the place, as did the gravity of Uranus and particularly Neptune as they edged outwards. These migrations led to the formation of the asteroid belt and the Kuiper belt, and ejected trillions of bodies into the wide orbits of the Oort Cloud.

"The key question is, if DJ has been relocated in the inner asteroid belt, then how many other asteroids came along with it and ended up being closer to the Earth, where they could have delivered some water, some organics and other things to our planet?" asked Marchi.

Lucy will visit six of Jupiter's trojans, which in total number over 15,300 discovered so far. Far from lumps of rock, the trojans, along with DJ and Dinkinesh (which is the Ethiopian name for the Lucy fossil), are windows into the past, and the storytellers of the Earth's most ancient history.

Lucy's findings from Donaldjohanson were published on Thursday (June 18) in the journal Science.

Earth got some of the key ingredients for life from asteroids in the inner solar system – with a little help from the solar system's largest planet, Jupiter, according to a recent study.

To figure out why we’re all here, and whether anyone else might be out there in the universe, scientists have to start with a more basic question: how did Earth get its supply of the chemicals that make up living cells?

According to Rice University planetary scientist Rajdeep Dasgupta and his colleagues, Earth’s stockpile of phosphorus and nitrogen, two chemical elements essential to life, came mostly from chunks of rock that formed in the inner solar system. And that process might not have happened without Jupiter looming just outside the asteroid belt.

"For our own solar system, Jupiter's presence and growth history indeed seem to have played a critical role in determining the distribution of the basic chemical ingredients necessary for habitable worlds," said Dasgupta in a NASA press release. "It remains an open question whether a life-essential elements budget similar to Earth's can be estimated without a Jupiter-like planet in the population."

Jupiter scores an assist

Dasgupta and his colleagues combined lab experiments and computer simulations to map the proportions of nitrogen and phosphorus, two chemical elements essential to life, in the early solar system. Life as we know it is literally built on these two elements; you can't build amino acids without nitrogen, and you can’t build DNA or RNA without phosphorus.

Other elements are also essential: carbon, hydrogen, oxygen, and sulfur, but how Earth got its phosphorus, in particular, has gotten less attention from researchers so far.

When scientists are investigating how Earth might have received the ingredients for life, one big clue is the ratio of each element to the others. Those proportions can form sort of a chemical fingerprint pointing back to the elements’ original source. In this case, looking at the ratio of phosphorus to nitrogen in present-day Earth’s rocky bulk could shed some light on where Earth’s phosphorus came from.

In the lab, the researchers simulated how different elements sort into layers as a newly formed asteroid cools, causing molten rock to crystallize. They also used computer simulations to model how different groups of planetesimals, clumps of metal and rock that coalesced out of the swirling disk of dust around the newborn sun, became the seeds of potential planets, formed and moved around the early solar system – moving phosphorus and nitrogen with them.

It turns out that present-day Earth contains phosphorus and nitrogen in about the same proportions as rocky planetesimals that formed in the inner solar system, the area between Jupiter and the Sun, around 4.3 to 4.2 million years ago.

Dasgupta and his colleagues’ models suggest that these chunks of rock, part of our solar system’s second generation of planetesimals, probably brought their shares of phosphorus and nitrogen to Earth as our planet was still forming. In a lot of cases, Earth’s gravity probably captured these objects and pulled them in, adding them to its growing bulk. Others got flung toward the accreting planet by collisions or close encounters with other objects, and Jupiter played a key role in that process.

Jupiter formed before Earth, and its tremendous gravitational influence shaped how material flowed through the disk of gas and dust that orbited the young sun.

Before Jupiter loomed onto the scene, material in the disk tended to flow outward, carrying its stores of phosphorus and nitrogen with them. However, Jupiter's hulking presence blocked most of that flow, keeping more of that rock, dust, and gas trapped in the inner solar system.

As the second generation of planetesimals was forged in the inner solar system around 4.3 to 4.2 million years ago, with Jupiter presiding, they formed with a higher ratio of phosphorus to nitrogen than their older siblings out beyond Jupiter's orbit.

Thus, the solar system's most massive world played a key role in distributing elements throughout the solar system, including those vital to life that were later delivered to Earth by asteroids that impacted our planet in its infancy.

Dasgupta and his colleagues published their work in the journal Science Advances.

The asteroid impact that doomed the dinosaurs may also have built one of Earth's longest-lasting underground ecosystems.

When a roughly 6-mile-wide (10-kilometer-wide) asteroid slammed into what is now Mexico's Yucatán Peninsula 66 million years ago, it triggered a global catastrophe that wiped out about 75% of life on Earth, including all non-avian dinosaurs.

However, that same impact may also have created a vast underground environment capable of supporting microbial life for at least 8 million years — four times longer than scientists previously believed, according to a new study.

Using updated computer simulations, researchers found that the hydrothermal system generated beneath the famous Chicxulub crater persisted far longer than expected, making it the longest-lived impact-generated hydrothermal system yet documented on Earth.

"Wherever on Earth you find flowing warm water, you find life, and we've known for a while that asteroid impacts create hydrothermal systems," Annemarie Pickersgill, co-author of the study from the Scottish Universities Environmental Research Centre (SUERC), said in a statement. "Previous research undertaken in the early 2000s suggested that the system created by the Chicxulub impact lasted for about two million years. Those findings were based on computer models which were, even at the time, regarded as conservative estimates, but we were still surprised by the outcomes of our research."

The Chicxulub impact excavated a crater nearly 125 miles (200 kilometers) wide and unleashed enormous amounts of heat deep into Earth's crust. In the aftermath, seawater from the Gulf of Mexico infiltrated fractured and melted rock beneath the crater, creating a network of hot, water-filled pores and cracks — conditions that scientists consider highly favorable for microbial life.

The new study combines advanced geological simulations with evidence collected directly from the crater itself. In 2016, scientists drilled into Chicxulub's "peak ring" as part of International Ocean Discovery Program Expedition 364, recovering rock samples from deep beneath the seafloor. Among the materials they collected was a potassium-rich feldspar mineral that formed as hot fluids circulated through the crater after the impact.

Using what are known as argon-argon dating techniques, the researchers determined that these minerals formed over a surprisingly long period, spanning from the time of the impact 66 million years ago until roughly 58 million years ago. This indicates that hydrothermal activity persisted for at least 8 million years, according to the statement.

To understand how the system remained active for so long, the team ran updated computer simulations incorporating modern geological data and more sophisticated models of heat and fluid flow. Their results suggest that several factors worked together to sustain the underground environment, including highly permeable fractured rocks, lingering heat from the impact itself and the region's natural geothermal energy.

"Advancements in computational methods enable researchers to simulate complex natural systems with unprecedented realism, bringing us even closer to unveiling mysteries of chaotic physical processes that shape Earth and other planetary bodies through geological timescales," Evangelos Christou, co-author of the study and former doctoral researcher at the University of Glasgow, said in the statement.

Hydrothermal environments are believed to have played a crucial role in the origin and evolution of life on early Earth. Therefore, if impact-generated systems can remain active for millions of years, they could provide stable habitats where microbial communities can emerge and thrive even after catastrophic events like Chicxulub.

The results of the study may also help guide future searches for life elsewhere in the solar system. Mars, for example, has endured countless asteroid impacts and may have once had surface water billions of years ago. Much like Chicxulub, large impacts on the Red Planet could have created similar underground hydrothermal systems capable of sustaining life long after surface conditions became hostile.

"The porous, fractured rocks created by impacts create microenvironments where microorganisms can be protected from radiation and extreme temperatures," Pickersgill said in the statement. "Those conditions give life the chance to take hold and flourish, and that is likely what happened here on Earth billions of years ago."

Their findings were published June 9 in the journal Communications Earth & Environment.

A newly discovered asteroid the size of an adult blue whale is set to fly past Earth today (May 18) at 24% of the average Earth-moon distance, and you can watch the event unfold in real time from the comfort of your home with this Virtual Telescope Project livestream.

The near-Earth asteroid 2026 JH2 was discovered on May 10 by the Mount Lemmon Survey in Arizona. Follow-up observations estimate the asteroid measures between 52 and 114 feet (16-35 meters) based on its apparent brightness, according to ESA.

2026 JH2 will make its closest approach to Earth at 5:23 p.m. (2123 GMT) on May 18, when it passes within 56,628 miles (91,135 kilometers), while traveling at 19,417 mph (31,248 km/h) relative to Earth.

How to watch the flyby live online

The free Virtual Telescope Project YouTube livestream will begin at 3:45 p.m. EDT (19:45 GMT) on May 18, weather permitting.

"At the time of the observation, the object will be moving pretty fast against the stars, but our advanced telescopes will precisely track 2026 JH2 while it will be almost at its minimum distance from us, peaking in brightness, around magnitude 11.5, before it will set below our horizon," Virtual Telescope Project founder Gianluca Masi told Space.com in an email.

2026 JH2 poses no threat to the moon or Earth during its close approach, but should shine bright enough to be spotted by the organization's telescopes in Manciano, Italy.

"We will see it like a sharp dot of light, moving against the starry background, with stars leaving long streaks, as we will be tracking the asteroid," Masi explained.

Having shot past Earth, 2026 JH2 will embark on a 3.8-year round trip that will see it venture out close to the orbit of Jupiter before tracking an elliptical path back towards the sun, according to the European Space Agency. Its next close pass of our planet won't come until the year 2060, when it will pass 17 times the Earth-moon distance.

Dante's famous 14th century epic poem, "Inferno," which is the first part of the Italian writer's "Divine Comedy," represents the first time a giant impact of a massive object falling from the heavens was envisaged, according to an expert in the specialized field of geomythology.

In the poem, the massive object in question is the Devil himself, Lucifer, who fell onto the Earth after being expelled from heaven. Yet, according to Timothy Burberry of Marshall University in West Virginia , this fall and subsequent impact is described by Dante in very similar terms to an asteroid impact. Burberry is a professor of English and an expert in geomythology, a field which involves searching old folk tales, myths and stories for evidence of real geological events. Written between 1308 and 1321, Dante's "Inferno" depicts the main character — Dante himself — being guided through Hell by the spirit of the ancient Roman poet Virgil. In what is considered one of the greatest works in the history of European literature, Dante and Virgil travel to the Underworld, where they are taken across the River Styx to Hell by the ferryman Charon — in fact, two of Pluto's moons, Charon and Styx, are named after these details.

The characters then cross the nine concentric circles of hell, beginning with Limbo and then various circles where the souls of those who commit different sins end up. Along the way, the poets encounter the likes of Cleopatra and the various antagonists of the Trojan War — Achilles, Helen of Troy and Paris — in the second circle where those who fell under the sin of lust end up. Further into Hell, in the seventh circle, those who committed great violence, such as Alexander the Great and Attila the Hun, are found. And at the very center of Hell is Satan himself, the traitorous Archangel Lucifer, depicted as a monstrous creature with wings and three heads. Each of those three heads is literally eternally chewing on the bodies of history's three greatest traitors up to that point, at least from Dante's point of view: Brutus and Cassius who had Julius Caesar murdered, and Judas Iscariot who betrayed Jesus.

The pertinent part, from the point of view of Burberry, comes towards the end of Inferno. Dante and Virgil escape Hell by clambering down Satan's monstrous hide and through Earth's center of gravity. Having descended from the northern hemisphere, they climb back up into the southern hemisphere.

Back in the 1300s, the Earth's southern hemisphere was largely unexplored and considered to be mostly ocean — indeed, even today we know it to be 81% ocean. However, Virgil explains to Dante that long ago the southern hemisphere had been completely covered in land. When God expelled Lucifer from heaven, Lucifer plummeted to Earth, smashing through the surface and continuing to burrow down until he reached the center of the planet, creating Hell. The displaced rock raced to the surface, forming the Mountain of Purgatory (which Dante and Virgil climb up in Dante's "Purgatorio," which is the second part of the "Divine Comedy"), becoming the central peak of a multi-ringed crater, the rings forming the nine concentric circles of Hell. The land of the southern hemisphere pulled away from this vile impactor, restructuring itself in the northern hemisphere.

Burberry therefore argues that what Dante is describing is an impact of an asteroid or a comet, violent enough to restructure large parts of the Earth. Perhaps it was similar to the impact thought to have contributed to the extinction of the dinosaurs 66 million years ago, or even the impact that formed the moon 4.5 billion years ago.

If Burberry is correct, then this would be remarkable foresight from Dante.

In the fourteenth century the heavens were considered to be (mostly) fixed and eternal and the concept of things falling to Earth from the stars was unheard of. In fact, it took until the first half of the nineteenth century for meteors to be recognized as being a celestial, not atmospheric, phenomenon, and that meteorites came from space.

"Although Dante was not a scientist, he was one of the first persons in history to think through the physical effects of a large mass slamming into the Earth at high speed," writes Burberry in the abstract of his paper about the subject. "In Dante's vision, the Devil's size and velocity are such that when he lands, he instantly creates Hell: a massive, circular, terraced crater that reaches to the center of the Earth."

Regardless of whether Dante meant to depict an impact from space or not, it does illustrate how geomythology can preview threats from natural disasters long before our scientific knowledge can catch up, argues Burberry. Given the era in which Dante's "Inferno" was written, before Copernicus and Galileo, by describing something falling to Earth Dante was highlighting an idea that indeed went against the established norm at that time.

Burberry presented his research in a poster at the European Geosciences Union General Assembly in Vienna, Austria, held between May 3–8.

In 2020, Japan's Hayabusa2 spacecraft brought samples of an asteroid named Ryugu to Earth — and now, scientists examining those samples found that the object bears the scars of a recent encounter with tiny space rocks.

The reason the research team believes Ryugu was bombarded by micrometeorites is due to a fine layer of sodium, just 10 nanometers thick, on the surface of the asteroid's fragments. This kind of build-up is unusual because volatile elements like sodium, which can get exposed after an object is blasted with micrometeorites, are usually later depleted by solar winds blowing from the sun and the general influence of space.

Based on the volume of sodium observed by the researchers, they estimate that Ryugu's passage through a dense cloud of micrometeorites must have occurred around 1,000 years ago. That's an extremely recent event considering the asteroid formed 4.6 billion years ago, while planets like Earth were still taking shape around our infant sun.

"Over the past thousand years, the asteroid has passed through a particularly intense swarm that has profoundly altered the chemical properties of its surface. We were able to detect these changes by analyzing two millimeter-thin fragments of Ryugu, using techniques capable of studying the morphology and chemistry of layers just a few billionths of a meter thick," lead researcher Ernesto Palomba of the Italian National Institute for Astrophysics (INAF) said in a statement translated from Italian. "In this context, finding an accumulation of sodium on particles collected on the surface and exposed to external agents is a puzzle we needed to solve."

"Experiments show sodium depletion of up to 50% over very rapid timescales, on the order of a few hundred years," Palomba added. "Based on these data, we considered a maximum time window of a thousand years, beyond which the sodium should have been completely released, making it impossible to observe any accumulation."

The team also discovered evidence of micrometorite impacts in the form of glassy formations, or tiny impact craters, and lattice-like microstructures created by interactions with the solar wind.

"The iron enrichment found in the particle collected on the surface can be traced back to interaction with the solar wind and continuous microimpacts," Palomba said. "This trend, already observed in previous studies, confirms once again that the exposed particle has undergone a more marked alteration than the one that remained protected underground."

The team's findings demonstrate how near-Earth asteroids close to our planet encounter swarms of meteoroids that are capable of altering their surface properties.

"This, in a sense, is what happens to our planet: in the case of Earth, the atmosphere protects us and allows encounters with these swarms to become a beautiful spectacle that periodically lights up our sky, as in the case of the Perseids or the Geminids," Palomba said. "For bodies without an atmosphere like the asteroid Ryugu, however, the outcome is different."

The INAF researcher said the team's next goal will be to conduct specific experiments on chemicals present on the asteroid Ryugu, to reproduce observations of the asteroid's surface chemistry.

The team's research was published on April 16 in the journal The Astrophysical Journal Letters.

A rare naked-eye asteroid will light up the night sky on April 13, 2029, when the near-Earth asteroid 99942 Apophis makes an extraordinarily close flyby of Earth. For skywatchers, it's a once-in-a-lifetime event — and one worth traveling for.

The Sahara Desert cools fast after sunset, and April's stars come out quickly. One by one, the stars appear — Leo, the Lion, stretching across the southern sky towards Gemini, the twins standing side by side. Between them, I find a swarm of starlight — the Beehive Cluster (M44) — hundreds of suns suspended in the perfect desert sky. Then I see what I came to Africa for. Just below the swarm, there's a new point of light. It's no ordinary object. Older than Earth's continents, older than life itself, wandering through space for billions of years — an agent of chaos here for a fleeting visit. Here today, gone tomorrow.

On Friday, April 13, 2029, this imagined moment becomes real when asteroid Apophis will make one of the closest approaches ever recorded for an object of its size. The night sky will tell a story billions of years in the making. Here's how to prepare for that story — and see something extremely rare on human timescales.

What's happening and when to look

At its nearest point — 5:45 p.m. EDT (2145 GMT) on April 13, 2029 — it will pass closer than Earth's geosynchronous satellites, at a distance of roughly 20,000 miles (32,000 kilometers). Just over an hour earlier, at 4:30 p.m. EDT (2035 GMT), it will reach peak brightness, with a magnitude of around 3.1. That's bright enough to be seen with the naked eye from dark locations — but only some locations.

For observers in Europe, Africa and western Asia, Apophis will appear for one night only. An asteroid this big, getting this close to Earth, happens only once every few thousand years, making it truly a once-in-a-lifetime opportunity for a celestial encounter both dramatic and deeply humbling.

Why all the fuss about Apophis?

Friday, April 13, 2029, was once predicted to become Earth's unluckiest day ever. Discovered in 2004, Apophis initially sparked global concern when early calculations suggested a possible impact with Earth — hence its name, Apophis, the Ancient Egyptian deity of chaos. Subsequent observations and radar tracking ruled out any collision risk for at least the next century. Today, it is classified as a "potentially hazardous asteroid," not because it poses a current danger, but because of its size and proximity.

Roughly 1,230 feet across (375 meters), Apophis is thought to be an elongated, rocky asteroid. It's close pass in 2029 offers scientists an extraordinary opportunity to study how Earth's gravity may alter its rotation, surface, and internal structure.

"The Apophis flyby will be an extraordinary event," Nick Moskovitz, a planetary scientist at Lowell Observatory in Flagstaff, Arizona, told Space.com. "Apophis will come so close that it will be visible to the naked eye and will feel a strong tidal pull from the Earth. The effects of these tides will include changing the spin rate of Apophis, seismic shaking of its interior, and maybe even landslides on the surface." It's the first time that scientists will witness an event of this kind, and space agencies are ready.

From an observer's point of view, it will be an extremely rare chance to detect an asteroid's motion relative to a background star over 5-10 minutes — most asteroids require hours or nights to show motion.

Missions to Apophis

The European Space Agency's proposed Ramses mission aims to launch in 2028 to observe the asteroid up close before and during its flyby, while NASA's OSIRIS-APEX is scheduled to orbit Apophis in June 2029 to see how the close encounter with Earth affected it. The latter is the same spacecraft that, as OSIRIS-REx, dropped off a sample from asteroid Bennu in 2023 before positioning itself for the visit of Apophis. ExLabs also intends to launch a commercial mission, called Apophis EX, to rendezvous with the asteroid.

"The best way to study this event will be with in situ spacecraft watching closely as the effects of the encounter unfold," Moskovitz said. "Data from these observations will ultimately provide new insights into the internal structure and surface properties of asteroids, and how they evolve during close planetary encounters."

How and when I'll watch Apophis

For me, this isn't just an event to note on a calendar — it's something to travel for and to see. I'm not the only frequent astrotourist with the Apophis bug; solar eclipse cartographer Michael Zeiler has already prepared incredible maps of the Apophis flyby on his website, EclipseAtlas.com.

The plan is to head somewhere where Apophis will be at its brightest, with low humidity and minimal cloud cover. Tenerife in the Canary Islands is firmly on the shortlist —a truly world-class astronomy destination, where high-altitude sites often sit above the clouds — as well as Mauritania and Morocco. Coastal regions such as southern Spain remain viable, though slightly less reliable due to higher cloud cover.

Clear skies are everything. Over the coming months and years, I'll be poring over visibility maps and long-term cloud data, trying to stack the odds in favor of a perfect view. But even then, there are no guarantees. This is part of the appeal — and the tension — of astronomy and astrotourism. You can plan everything perfectly and see nothing. What I do know is that the Apophis flyby coincides with a new moon and the bright opposition of Jupiter, so maybe the gods (of chaos) will be smiling on us asteroid pilgrims below.

Stargazer's corner: April 13-19, 2026

You don't need to wait until 2029 to look up, and this week brings some great opportunities to get used to getting up incredibly early for the sake of stargazing. This week will see Comet C/2025 R3 (Pan-STARRS) reach its brightest, with the best time to look to the east about 90 minutes before sunrise, where you are. Find an unobstructed eastern horizon, best done from a second or third (or higher) story. Look between the stars Markab and Algenib in the Great Square of Pegasus — and the sooner, the better, before it gets closer to the horizon during the rising dawn. While you're out, it will be worth staying outside a little longer on Monday, April 13, Tuesday, April 14 and Wednesday, April 15 to see a waning crescent moon move through the twilight, with a chance to see Mercury, too. On Saturday, April 18, comet Pan-STARRS will get to within a couple of degrees of galaxy NGC 7814, a distant edge-on spiral.

Constellation of the week: Corona Borealis

A small constellation now becoming visible in the Northern Hemisphere's night sky, Corona Borealis — meaning Northern Crown — is a curve of seven stars between bright stars Vega and Arcturus (though slightly closer to the latter). It's worth finding because it's beautiful, but also because its very faint star T Coronae Borealis, also called T CrB and the "Blaze Star," may explode this year and become visible in the night sky for a few weeks. It's low in the east-northeast around midnight.

A house-size asteroid will make a close pass of Earth and the moon tonight (April 9), passing a little over half the distance to the moon as it buzzes the southern hemisphere at a blistering speed of 28,030 miles per hour (45,109 kilometers per hour).

The asteroid, designated 2026 GD, was discovered on Monday (April 6) and is estimated to be 16 meters (54 feet) in diameter. The solar system wanderer will make its closest approach to Earth at 6:59 p.m. (2259 GMT) on April 9, when it will pass 155,760 miles (250,000 km), or 0.65 lunar distances, while moving at 28,030 miles per hour (45,109 kilometers per hour).

2026 GD will make an even closer approach to the moon a few hours later, at 8:12 p.m. EDT on April 9 (0012 GMT on April 10), passing just 101,000 miles (163,750 km) from the lunar surface while posing no threat to either Earth or its natural satellite.

The asteroid will also pose no threat to the crew of the Artemis 2 lunar mission, which is currently travelling between the moon and Earth ahead of its scheduled parachute-assisted splashdown off the coast of California on Friday (April 10).

Following the flyby, 2026 GD will continue along a 644-day elliptical path that takes it beyond the orbit of Mars before careening back towards the sun. Its next planetary encounter won't come until July 2031, when it will travel the equivalent of 25 lunar distances from Venus.

2026 GD's size and close orbit take it close enough to Earth to warrant a place on the European Space Agency's "Risk List" — a catalogue of near-Earth objects that pose a non-zero impact probability. Even so, it poses a cumulative impact probability of just 1/124,378 for orbits that will take it close to Earth between the years 2082 and 2124, according to ESA.

Early observations from the Vera C. Rubin Observatory have already revealed more than 11,000 previously unknown asteroids, reshaping our view of the solar system and offering a striking preview of what's to come once full science operations begin.

The discovery, made using preliminary data, demonstrates Rubin's ability to scan the sky quickly and deeply. Even during limited early observations, the telescope has detected thousands of moving objects in just days, far outpacing traditional asteroid surveys, according to a statement from the NSF NOIRLab.

"This first large submission after Rubin First Look is just the tip of the iceberg and shows that the observatory is ready," Mario Juric, Rubin Solar System Lead Scientist, said in the statement. "What used to take years or decades to discover, Rubin will unearth in months. "We are beginning to deliver on Rubin's promise to fundamentally reshape our inventory of the solar system and open the door to discoveries we haven't yet imagined."

Astronomers currently know of roughly 1.4 to 1.5 million asteroids across the solar system, most of which are concentrated in the main belt between Mars and Jupiter. Rubin is expected to dramatically expand that number, potentially discovering millions of new objects over the course of its 10-year Legacy Survey of Space and Time. The observatory's 8.4-meter mirror and massive camera — the largest ever built for astronomy — allow it to repeatedly image the entire southern sky every few nights, making it uniquely suited to spotting faint, fast-moving objects.

Even in its earliest data, Rubin is uncovering a wide range of asteroid populations. Most of the new discoveries are main-belt asteroids, but the observatory has also identified 33 previously unknown near-Earth objects (NEOs) — asteroids and comets whose orbits bring them close to the sun and are, therefore, of particular interest for planetary defense. However, none of the newly discovered NEOs pose a threat to Earth, according to the statement.

In addition, the telescope has detected more distant and less common populations, including roughly 380 trans-Neptunian objects (TNOs) — icy bodies orbiting beyond Neptune. To find them, scientists developed advanced computational methods that sift through massive datasets, using algorithms to scan millions of faint light sources and test billions of possible motion paths to pinpoint the slow, subtle movements of these distant worlds. Together, these finds offer a more complete picture of the structure and history of the solar system.

"Objects like these offer a tantalizing probe of the solar system's outermost reaches, from telling us how the planets moved early on in the solar system's history, to whether a hitherto undiscovered 9th large planet may still be out there," said Kevin Napier, a research scientist at the Harvard-Smithsonian Center who helped developed the algorithms to detect distant solar system objects with Rubin data.

The recent discoveries extend beyond cataloging. Planetary defense efforts rely on finding and tracking NEOs that could pose a risk to Earth. While many larger objects have already been identified, a significant fraction of smaller — but still potentially dangerous — asteroids remain undiscovered. Astronomers estimate that once Rubin is fully operational, it will increase the number of known larger NEOs from only 40% up to 70% through continuous monitoring. The telescope's ability to revisit the sky frequently will allow astronomers to detect these objects earlier and calculate their orbits with greater precision, improving advance warning capabilities and offering new insights into how asteroids form, evolve and move through the solar system, officials said in the statement.

"Even with just early, engineering-quality data, Rubin discovered 11,000 asteroids and measured more precise orbits for tens of thousands more," Ari Heinze, who helped build the software that detected them, said in the statement. "It seems pretty clear this observatory will revolutionize our knowledge of the asteroid belt."

Current surveys discover tens of thousands of asteroids per year. Rubin, by contrast, has already demonstrated it can find thousands in just a short span of early observations. These first 11,000 discoveries are only the beginning. With Rubin poised to turn the night sky into a dynamic, continuously updated map of moving objects, astronomers are entering a new era of solar system science — one that could both deepen our understanding of our cosmic neighborhood and help protect the planet.

The European Space Agency's Hera spacecraft has completed a major deep-space maneuver, setting it on course to rendezvous late this year with the asteroid system targeted by NASA's DART mission back in 2022.

Hera launched on a SpaceX Falcon 9 rocket in October 2024, beginning its voyage to the Didymos binary asteroid system. Hera is designed to make follow-up observations of Dimorphos, the smaller of the two asteroids, which NASA's DART (Double Asteroid Redirection Test) spacecraft slammed into in September 2022.

The Hera spacecraft made a flyby of Mars one year ago, in March 2025, testing its autonomous vision-based navigation and training its cameras on the Martian moon Deimos, while also setting itself on course for the Didymos system.

Hera is now set up for its rendezvous with the asteroids in November 2026, thanks to a campaign of carefully planned engine burns that it performed in February and March.

"We divided the deep-space maneuver into three engine burns, plus one much smaller correction maneuver, carried out over a period of around four weeks," Francesco Castellini from the Flight Dynamics team at ESA's European Space Operations Centre in Germany, said in a March 17 statement.

"This is the Hera mission's largest maneuver in terms of fuel consumption, and we used it to test all of the systems that we will need during the braking and rendezvous maneuvers later this year as we arrive at Didymos," Castellini added.

These maneuvers burned 123 kilograms (271 pounds) of onboard hydrazine fuel and changed the spacecraft's velocity by 367 meters per second (1,204 feet per second) — about 821 mph (1,321 kph). This amounts to "a change comparable to an object accelerating from stationary to supersonic flight," ESA officials wrote in the same statement. ESA's Estrack network of deep space antennas confirmed the success of the engine burns.

Scientists are now beginning preparations for arrival at the asteroid system, including extensive onboard software updates.

Hera will begin a series of precision burns in October to shift the spacecraft out of its interplanetary cruise phase and set up rendezvous with the Didymos system. The spacecraft and its 12 payloads will spend at least six months studying the system, beginning with early global studies and then deploying its Milani and Juventas cubesats, before then embarking on a more detailed mapping exercise. The primary mission will culminate in an experimental, close-up inspection of the DART impact crater from an altitude of around 1 kilometer (0.62 miles).

The aim of the series of detailed follow-up studies of Dimorphos is to help transform DART's one-off kinetic impactor experiment into a repeatable, scalable asteroid-deflection method.

While humanity's knowledge of our solar system's small worlds is slowly growing thanks to missions from across the globe, such as NASA's OSIRIS-REx (now OSIRIS-APEX), JAXA's Hayabusa2 and China's Tianwen-2, Hera will also be performing the first survey of a binary asteroid system.

Scientists recently revealed that DART slamming into the 560-foot-wide (170 m) Dimorphos also altered the orbit of Didymos, the much larger asteroid of the pair at roughly 2,788 feet (850 m) across. This unexpected outcome could provide new insights into binary asteroid systems and, crucially, how their orbits change after impacts.

A car-sized asteroid will buzz Earth at a little over half the Earth-moon distance late tonight (March 24), just three days after its discovery by the Zwicky Transient Facility at the Palomar Observatory in California.

The close encounter between Earth and the asteroid designated 2026 FM3 will occur at 10:07 p.m. EDT on March 24 (0207 GMT on March 25). The flyby will see the solar system object pass 147,836 miles (237,918 kilometers) from our planet's southern hemisphere — only 61.9% of the distance to the moon — while travelling at 11,461 miles per hour (18,444 kilometers per hour), according to NASA.

2026 FM3, which has an estimated diameter of between 4-8 meters (13-26 feet), will shoot past the moon a little over three hours later at a distance of 370,022 miles (595,492 km), posing zero risk to either body.

Early observations have revealed that the asteroid travels a near circular path around the sun that intersects Earth's orbit twice over the course of its 354-day period. The asteroid's closest known brush with our planet occurred in September 1965, when it missed Earth by just 30,559 miles (49,181 km) — a hair's breadth in astronomical distances.

However, current observations show that 2026 FM3 will make no such close approaches to Earth over the next 100 years, and it is far too small to be considered a potentially hazardous asteroid by NASA's Center for Near Earth Object Studies regardless.

The dense gaseous shell of Earth's atmosphere forms a protective barrier against smaller asteroids, which can on occasion be seen forming brief, fiery trails in the sky in the form of meteors, or "shooting stars". Larger pieces of debris create dramatic fireballs, as was seen in recent events that occured over Ohio and Texas, which can fragment to scatter chunks of debris over the land below.

2026 FM3 is just one of over 41,000 near-Earth asteroids discovered to date — a number that is likely to swell dramatically as powerful new observatories come online, such as the Vera Rubin Observatory, which pinpointed the locations of 2,000 previously unknown asteroids in its initial dataset.

Editor's note: This article was updated to reflect the reflect the correct percentage of the lunar distance that the asteroid will pass from Earth.

NASA has used advanced imaging techniques to peer inside samples of an asteroid, discovering extensive networks of cracks running throughout the rock particles.

What is it?

These images show two different views of two small rock particles NASA's OSIRIS-REx probe collected from asteroid Bennu. NASA has been peering inside the samples using X-ray computed tomography (XCT), a special type of imaging that can reveal the interiors of objects without damaging them.

These scans have revealed that the samples contain networks of fine cracks. Scientists can now use this discovery to understand why Bennu appears to have such low thermal inertia, meaning its surface heats up and cools down rapidly as different faces of the asteroid rotate in and out of sunlight.

One theory to explain this feature of Bennu was that the object might be more porous than telescopic observations of its boulder-strewn surface suggested. However, scientists needed a detailed analysis of the asteroid samples to confirm this theory  —  and that's what they just got.

"It turns out that they're really cracked too, and that was the missing piece of the puzzle," said Andrew Ryan, who led the OSIRIS-REx sample physical and thermal analysis working group, in a NASA statement.

Why is it amazing?

These images offer a rare look inside a piece of the early solar system. This study could help scientists better predict the structures of asteroids based on the thermal properties we can observe from Earth using telescopes and other instruments — in other words, without needing to collect physical samples.

In September 2023, NASA returned samples of asteroid Bennu collected by the historic OSIRIS-REx mission. The samples landed in the Utah desert after OSIRIS-REx made a 4-billion-mile (6.2-billion-kilometer) journey from Earth to Bennu and back again.

NASA has been studying the Bennu samples, and has already discovered that they contain amino acids — some of the "building blocks" of life as we know it — and appear to be older than our own solar system.

Scientists have discovered that a sample of the Ryugu asteroid collected by Japan's Hayabusa 2 spacecraft contains the nucleobases adenine, guanine, cytosine, thymine and uracil, the building blocks of DNA and RNA upon which all life is based.

Because asteroids like Ryugu formed 4.6 billion years ago when the planets were being born around the infant sun, and have remained relatively unspoiled since, the discovery sheds new light on the chemical conditions that existed at the dawn of the solar system.

Adenine, guanine, cytosine, and thymine are the four bases of the genetic code that make up the rungs of the double helix structure of DNA by forming specific pairs (adenine pairs with thymine, guanine with cytosine). In RNA, uracil replaces thymine to pair with adenine. The detection of these molecules in an asteroid hints that they can be formed without the presence of life, and may offer clues into how these compounds could be transported across the solar system.

The Japanese Aerospace Agency (JAXA) Hayabusa 2 mission collected samples from the asteroid Ryugu between 2018 and 2019. The spacecraft returned these samples to Earth on Dec. 5, 2020.

Carbonaceous asteroids like the spinning-top-shaped Ryugu contain what is effectively a "fossil record" of unspoiled material from the earliest era of the solar system, hence why scientists are so keen to get them back here to Earth to study up close and in person.

The study of the two samples returned to Earth has previously demonstrated that Ryugu once had liquid water flowing across its surface, strengthening the theory that these space rocks may have delivered water to the surface of our planet.

This team, led by JAXA biogeochemist Toshiki Koga, analysed two Ryugu samples returned by Hayabusa 2, finding adenine, guanine, cytosine, thymine, and uracil. The results were compared to findings reached when researchers studied samples returned from the asteroid Bennu, and to investigations of the Murchison and Orgueil meteorites, collected from Australia in 1969, and France in 1864, respectively. The team discovered significant differences in the concentrations of nucleobases.

Ryugu contains roughly comparable amounts of the nucleobases, adenine and guanine (known as purines), to cytosine, thymine, and uracil (pyrimidines). Murchison, however, is richer in purine nucleobases, while Orgeuil samples from Bennu are richer in pyrimidine nucleobases.

These disparities could reflect the different evolutionary histories and environmental birthplaces of Ryugu, Bennu, and the parent bodies of the Murchison and Orgeuil samples. The research further emphasizes the role asteroids likely played in building the chemical diversity that allowed life to arise on Earth.

Perhaps the most significant result of this study is the implication that the building blocks of DNA and RNA are widely dispersed through the solar system.

The team's research was published in the journal Nature Astronomy.

The James Webb Space Telescope has helped scientists determine that asteroid 2024 YR4, which previously had a 4.3% chance of crashing into our moon, will not impact our lunar companion at all. Instead, it will instead safely cruise past the moon at an altitude of 13,200 miles (21,200 kilometers).

When asteroid 2024 YR4 was discovered on Dec. 27, 2024 by the NASA-funded Asteroid Terrestrial-impact Last Alert System (ATLAS), it was for a short time the most dangerous asteroid ever discovered. With a diameter of about 197 feet (60 meters) there was originally a non-zero chance that it could impact Earth on Dec. 22, 2032. An asteroid of this size could destroy a city, or if it struck the ocean, produce a catastrophic tsunami that would endanger multiple coastal regions.

However, it was quickly found that 2024 YR4 would miss the Earth — but it remained unclear whether it'd hit the moon instead. Specifically, there was a 4.3% chance that it could strike the moon on Dec .22, 2032 instead. The uncertainty was the result of 2024 YR4's orbit around the sun not being known as precisely as needed in order to decide for sure whether it would hit the moon or miss it.

Astronomers thought they would have to wait until 2028 to get the next chance to observe 2024 YR4 and refine its orbit before getting some clear answers, but researchers at the Johns Hopkins University Applied Physics Laboratory (JHUAPL) realized that there would be a chance for the James Webb Space Telescope (JWST) to observe 2024 YR4 between Feb. 18 and Feb. 26 this year.

During that week, the asteroid was moving against a faint field of stars whose positions have been precisely measured by the European Space Agency's Gaia mission. By tracking the object's motion against those stars, the James Webb Space Telescope (JWST) was able to refine its orbit to high precision. It wasn't an easy measurement; the field of view of its Near-Infrared Camera is just 2.2 square arcminutes, and the asteroid is one of the faintest targets the JWST has ever observed.

The scientists at JHUAPL worked with the space telescope’s engineers, alongside the European Space Agency's Near-Earth Object Coordination Centre and NASA's Center for Near-Earth Object Studies, to aim the telescope precisely.

The new measurements mean that astronomers have now ruled out a collision with the moon. Instead, 2024 YR4 will pass 13,200 miles above the lunar surface — still a very close encounter, but posing no danger.

Had the impact happened on the near side of the moon, it would have provided scientists with their first up-close view of a large impact, and provided a stunning sight for observers on Earth, resulting in a brilliant flash and a new crater about 0.62 miles (1 kilometer) across. The energy imparted would have been equivalent to 6 million tons of TNT, or basically a large nuclear detonation. Ejecta thrown up by the impact would mostly have rained back down onto the surface of the moon, but millions of pounds of debris would have still escaped the lunar gravity and fallen towards Earth instead, possibly creating a unique meteor shower lasting a few days. The debris would also have been a hazard to satellites in orbit around the Earth, and, as some of the debris could linger in Earth orbital space for years, that hazard would have been long-lasting.

However, now that we know 2024 YR4 will miss its target, we'll just have to wait for the next asteroid to worry about, and remain ever vigilant for any that may threaten Earth.

It's a cosmic roll of the dice. A major asteroid strike could cause widespread devastation and profoundly impact life on Earth, so thwarting an incoming object could be a matter of life or death.

Luckily, we have a little bit of practice at this. On Sept. 26, 2022, NASA's Double Asteroid Redirection Test (DART) slammed into Dimorphos, a moonlet that orbits a larger asteroid called Didymos. DART was the first-ever mission dedicated to trial-run one method of asteroid deflection by changing an object's motion in space through a kinetic impact.

The outlook of Earth being on the receiving end of a menacing asteroid in the future is real. And when the high-stakes card is dealt, responding to a hostile near-Earth object (NEO) is a global challenge.

Promoting protection

Enter the heads-up and off-world reality of the nonprofit B612 Foundation, which takes its name from Antoine de Saint-Exupéry’s 1943 novella "The Little Prince." (The prince lives on an asteroid called B-612.)

Since 2002, the Silicon Valley-based organization has engaged in research, education and promoting the protection of Earth from asteroid impacts, and also advancing knowledge about the solar system's evolution and expanding economic development in space.

Danica Remy is president of B612 and a co-founder of Asteroid Day, an international day of action and education about asteroids held every year on June 30.

"The idea [behind Asteroid Day] was that the public needed to be educated about both the risks as well as the aspirational opportunities that asteroids present to humanity," Remy told Space.com.

Public communications

Modeled after Earth Day, Asteroid Day is an important part of B612's worldwide public communications strategy, said Remy, "a way to elevate trusted voices and spokespersons about both the risk and the opportunities that asteroids present."

"In some ways, you still need a human network," she added. "That's because we actually don't know what trust looks like in this time of internet communications and artificial intelligence generation."

Asteroid Day was co-founded by astrophysicist and musician Brian May of the rock band Queen, along with Apollo 9 astronaut Rusty Schweickart, filmmaker Grig Richters and Remy. The day is recognized by the United Nations with hundreds of events held to sharpen public appreciation of asteroids.

Multidimensional work

Schweickart co-founded B612 and led it for its first 10 years. He was also instrumental in persuading Remy to join forces with former NASA astronaut Ed Lu in leading the effort.

"I convinced her that the planetary defense challenge, while having substantial technical challenges, was far broader than that," Schweickart told Space.com. "In fact, when the rubber hits the road regarding an impact threat, the major issues and decisions were largely non-technical."

Remy's efforts and talent in management, fundraising and organizational leadership have enabled the multidimensional work of B612 to grow "and become a highly productive planetary defense asset for the world," Schweickart said.

Two real-world impacts

Asteroid Day spotlights the anniversary of the 1908 Tunguska impact in Siberia, the largest asteroid hit on Earth in recorded history. That major wallop into shattered roughly 800 square miles (2,072 square kilometers) of forest — the approximate size of a major metropolitan city today.

A more recent Earth encounter with an asteroid occurred in February 2013, over the Russian town of Chelyabinsk. An asteroid about 60 feet (18 meters) wide detonated above the city, an unexpected sky show that damaged buildings and injured a large number of people on the ground. (Asteroids don't have a particular animus for Russia; the nation just covers a huge amount of territory, so it has a relatively high chance of being hit.)

It was a 21st century wakeup call, and also rang the bell to emphasize the range of B612 activities.

A techno-optimist

"My background is in the area of computer science," said Remy, who spearheads the organization's strategy and operations. She has an enviable track record of leading startups and nonprofits across diverse fields, including technology, internet services, education and philanthropy.

"I am a techno-optimist and really believe that technology can solve problems," Remy said. But, she added, "it will make a lot of problems, too, if we don't think well about the potential problems."

Remy says that the asteroid challenge is a data challenge.

"We simply don't know where the majority of them are, and we have the technology," she said. "In order to find and track them, we need to deploy those technologies or invest in those technology solutions to accelerate the rate of asteroid discovery."

For example, the Asteroid Institute, a program of the B612 group, is working on a way to utilize the latest advances in computing and astronomy to build "open tools" — easily accessible ways to understand, map and navigate our solar system.

The Asteroid Discovery Analysis and Mapping (ADAM) platform is a case in point. Built on Google Cloud, it combines curated datasets — 8.6 billion point sources — and cloud-based services to create the infrastructure for discovery, analysis and mission design.

Independent voices

ADAM is an open-source tool that handles impact probability, trajectory optimization and real-time discovery in one easily accessible interface, Remy said.

"The tools we are building are open source, so people can download and use the tools. They are an important part of transparency in this world of a lot of information from a lot of different places," she said. "We think that there should be an independent voice. We think that other people around the world are capable of doing some of this analysis for themselves."

It is important that computer and software-savvy individuals validate data about where an asteroid is and where it is traveling, making them credible sources of information, Remy said.

Discovery pipeline

"By making tools and information available, we think the world is better off having researchers, explorers and planetary defenders," Remy added. "People can be enabled to begin that exploration process for themselves, independent of an agency or an academic institution."

Lu is the executive director of the Asteroid Institute. In last year's Institute progress report, he emphasized the ground-based Vera Rubin Observatory's capabilities as the most powerful facility for asteroid discovery ever built.

Lu said that scientists will use ADAM with Rubin observations to identify and assess potential threats. The Institute is eager to apply its Trackletless Heliospheric Orbit Recovery (THOR) algorithm to expand the number of asteroids Rubin will uncover, he added.

THOR was developed by Joachim Moeyens at the University of Washington and the B612 Asteroid Institute. It can discover asteroids in datasets regardless of observational cadence by linking observations across time spans. The algorithm is being integrated into ADAM's discovery pipeline.

Democratize access to data

Remy thinks that public attention to space rocks will be heightened by the April 13, 2029 flyby of Earth by the asteroid Apophis, named after the Egyptian god of chaos.

"Apophis is a great story, and luckily, it doesn't have our address on it," she said. "And it's a really exciting adventure for all of humanity."

A growing cadre of national and international spacecraft missions will collect critical Aphosis data for current and future use. "The community is going to have access to that data. That's why I think it's so important that we democratize access to data, especially for science," said Remy.

Our planetary future

Similarly, there's another space rock lurking out there to keep an alert eye on: Asteroid 2024 YR4. Astronomers initially thought 2024 YR4 might be a troublemaker for Earth, but that prospect has dissipated. On the other hand, the asteroid may slam into Earth's moon on Dec. 22, 2032.

Experts give 2024 YR4 a 4% chance of striking our celestial neighbor on that date. "But remember, that means there's a 96% chance that it won't hit," Remy said. Still, such a hit would be "an amazing show through a telescope," she said, perhaps causing meteor showers here on Earth.

"While the B612 DNA was in planetary defense, our future and all of our investments for the last six years have been in mapping our solar system, not only for planetary defense but also for mission planning, for visiting asteroids and for discovery," Remy concluded. "The tools we are building are about our planetary future."

The origins of the building blocks of life may be even more widespread than we realized, as per a new discovery from the asteroid sample NASA's OSIRIS-REx mission brought back to Earth from the space rock Bennu.

At least 14 of the 20 amino acids used by life on Earth, and 19 other amino acids not used by life, have been identified in the sample from Bennu, which was delivered to Earth in September 2023. It had been thought that these amino acids had formed in warm, watery conditions close to the infant sun 4.5 billion years ago.

However, a new analysis of the isotopes contained within the amino acids points to a much colder origin for the compounds: in the presence of ice far away from the young sun.

"This confirms that life's building blocks can be formed in a diversity of environments throughout the universe," Allison Baczynski, an organic chemist at Penn State University and co-lead author of the new study, told Space.com.

Baczynski led a team who investigated the isotopic composition of Bennu's amino acids, focusing on the simplest amino acid in the sample, which is glycine. On Earth, glycine forms when hydrogen cyanide, ammonia and organic compounds called aldehydes react with each other in warm water. Baczynski's team used the Murchison meteorite that fell in Australia in 1969 as a reference; the amino acids found in Murchison have an isotopic composition that suggests they formed in this manner.

On the other hand, Bennu's glycine, and other amino acids present, have isotopic compositions that differ from the Murchison amino acids. Instead, their isotopic composition matches what could be expected from having formed in a chemically distinct and frozen environment farther from the sun, though still dowsed in the solar ultraviolet radiation required to trigger the reaction to form the amino acids.

"It was really exciting to see that amino acids in Bennu showed a much different isotopic pattern than those in Murchison, suggesting that the amino acids formed by a different pathway and in different regions of the solar system," said Baczynski.

The early solar system, during the era when the planets were still forming, was divided by a boundary known as the "snow line." Beyond the snow line, water was frozen, while inside the snow line it existed as liquid or vapor. Chemical reactions proceeded differently depending upon which side of the snow line they took place on.

It is not entirely clear whether the amino acids formed beyond the snow line on icy dust grains and then migrated inwards where they were accreted by Bennu's parent body (at some point in the past it was smashed apart by a collision, and Bennu is a large fragment of it), or whether Bennu's parent body itself formed beyond the snow line. However, the evidence points to the latter as being the probable origin.

"Our isotopic data indicates that the amino acids formed in a cold, icy environment and other data acquired by the OSIRIS-REx mission suggests that the parent body of Bennu formed beyond the snow line," said Baczynski.

A new mystery also came to light as part of the analysis of the isotopic composition of Bennu's amino acids. Amino acids can come in two forms, left- or right-handed, referring to how their molecular structure can be mirror-imaged. For reasons that no scientists yet understand, all life on Earth uses left-handed amino acids.

Scientists had thought that for any given type of amino acid, the left- and right-handed versions were otherwise identical. Yet the analysis of one of the amino acids in the Bennu sample, glutamic acid, reveals that the left-handed and right-handed versions have different nitrogen isotopes. Why they should be different is a mystery, and although glutamic acid is not one of the amino acids that life uses, the question is whether this has any connection with why life uses only left-handed amino acids.

"It has often been assumed that the nitrogen isotope values would be the same for both forms. It was surprising, therefore, to discover that while the L- and D-glutamic acid in Bennu were in equal proportion, the nitrogen isotope values were very different," said Baczynski. "This was one of the most intriguing findings and we're excited to explore this further."

The discovery that amino acids can form in more ways than we thought is another boost to the search for life beyond Earth. If life's building blocks can form in a wide variety of conditions, it increases the number of locations where we could potentially look for life.

The findings were published on Feb. 9 in the journal Proceedings of the National Academy of Sciences.

An unusual ratio of potassium isotopes, found in samples of basaltic rock brought back to Earth from the moon's South Pole–Aitken Basin by China's Chang'e 6 sample-return mission, has provided further evidence for how the impact that formed this gigantic basin is responsible for the asymmetry between the moon's near and far sides.

The moon's near side is familiar to us through the pattern of the 'Man in the Moon' that is made from the dark shapes of the lunar maria, which are vast volcanic plains. In contrast, the far side, visible only to spacecraft that go around the back side of the moon, has barely any dark maria.

The huge 1,600-mile (2,500-kilometer) wide expanse of the South Pole–Aitken Basin extends considerably onto the far side of the moon. It's one of the largest impact features in the entire solar system and is between 4.2 and 4.3 billion years old – much older than the lunar maria, most of which are estimated to be around 3.6 billion years old.

Chang'e 6 touched down inside the 334-mile (537 km) crater Apollo, which sits inside the South Pole–Aitken Basin, on June 1, 2024, and returned to Earth precious samples from its landing site 25 days later. Ever since, Chinese scientists have been carefully analyzing the samples to try to learn why the far side is so much different from the near side.

Now, a team led by Heng-Ci Tian of the Institute of Geology and Geophysics at the Chinese Academy of Sciences in Beijing has analyzed samples of lunar basalt brought back by Chang'e 6. The scientists found that the ratio of the heavier potassium isotope, potassium-41, relative to potassium-39 is greater in the samples from the South Pole–Aitken Basin than in samples from the near side collected by the Apollo missions and lunar meteorites.

Tian's team explored several possible explanations for this baffling isotopic composition. They considered whether the long-term irradiation of the lunar surface by cosmic rays could have resulted in the unusual isotopic ratio. They looked at whether the various melting, cooling, and eruptive processes of magma could have changed the composition of the basalts. And they explored whether the isotope ratio is a consequence of meteoritic contamination. Ultimately, they concluded that all of these processes would have only a minor effect, if any.

That left one other option: that the potassium isotope ratio is a relic of the giant impact that formed the South Pole–Aitken Basin. The intense temperature and pressure of the impact heated the moon's crust and mantle so much that many of the volatile elements present (volatiles are elements with low boiling points), including potassium, evaporated and escaped into space. Previous results support this – Chang'e 6 has already discovered that the mantle on the far side contains less water than the near side. Since the lighter potassium-39 isotope would be more susceptible to evaporating than the heavier isotope, the impact resulted in this greater ratio of potassium-41 to potassium-39.

Isotopic curiosities aside, the findings show how deeply the impact affected the moon's interior, and how isotopic ratios can provide windows into the conditions of such impacts, and how those impacts altered the moon's crust and mantle. The reduction in volatiles would limit volcanism by suppressing the formation of magma, providing a strong explanation for why the lunar far side contains so few maria.

The latest findings from the Chang'e 6 mission were presented on 12 January in Proceedings of the National Academy of Sciences.

A powerful new telescope in South America is already offering tantalizing hints of what it can do.

The Vera C. Rubin Observatory began studying the heavens from a Chilean mountaintop last spring, and its "first light" images wowed astronomers and space fans alike when they were released in June.

That initial dataset included observations of nearly 2,000 newly discovered asteroids, and we got some exciting new details about this group on Wednesday (Jan. 7). A new study reveals that 19 of the asteroids are "superfast rotators," completing one spin in less than 2.2 hours — and one is the fastest-spinning big asteroid ever found.

Like all but one of the newfound superfast rotators, the record-setting space rock, called 2025 MN45, resides in the main asteroid belt between Mars and Jupiter. The object measures about 0.4 miles (710 meters) across and completes one rotation every 1.88 minutes, making it "the fastest-spinning asteroid with a diameter over 500 meters that astronomers have found," according to a statement released Wednesday by the U.S. National Science Foundation's NOIRLab. (The Rubin Observatory is a joint program of NOIRLab and the Department of Energy's SLAC National Accelerator Laboratory.)

An asteroid's rotation rate can reveal key information about it. Extremely rapid spins, for example, may point to a violent collision that shattered a larger parent body. Rotation can also offer insight into an asteroid's internal structure and composition.

"Clearly, this asteroid must be made of material that has very high strength in order to keep it in one piece as it spins so rapidly," study leader Sarah Greenstreet, an NSF NOIRLab assistant astronomer and the head of the Rubin Observatory’s Solar System Science Collaboration’s Near-Earth Objects and Interstellar Objects working group, said in the same statement.

"We calculate that it would need a cohesive strength similar to that of solid rock," she added. "This is somewhat surprising since most asteroids are believed to be what we call 'rubble pile' asteroids, which means they are made of many, many small pieces of rock and debris that coalesced under gravity during solar system formation or subsequent collisions."

2025 MN45 isn't the overall spin-rate record holder. Astronomers have found a number of small asteroids — those just a few meters, or tens of meters, wide — that complete a rotation in less than a minute.

The Vera Rubin Observatory is still ramping up operations and has not yet begun its primary science mission. That effort, a 10-year project called the Legacy Survey of Space and Time (LSST), will create a wide-view, high-definition, time-lapse record of the universe. The survey will rely on images captured by the 3.2-billion-pixel LSST Camera, the largest digital camera in the world.

"We have known for years that Rubin would act as a discovery machine for the universe, and we are already seeing the unique power of combining the LSST Camera with Rubin's incredible speed. Together, Rubin can take an image every 40 seconds," Aaron Roodman, deputy head of LSST and professor of particle physics and astrophysics at SLAC, said in the same statement.

"The ability to find thousands of new asteroids in such a short period of time, and learn so much about them, is a window into what will be uncovered during the 10-year survey," he added.

The new study was published Wednesday in The Astrophysical Journal Letters. The results were also presented during a press conference that day at the 247th meeting of the American Astronomical Society in Phoenix, Arizona.

Space fans hoping that the intruder from beyond the solar system known as Comet 3I/ATLAS is actually an alien spacecraft may be disappointed by new research that could close the book on this speculation once and for all.

Astronomers used the Green Bank Telescope, employed in the Breakthrough Listen extraterrestrial signal-hunting astronomy project, to search 3I/ATLAS for measurable signs of technology from extraterrestrial civilizations, or "technosignatures."

Though this hunt came up empty, the fact that 3I/ATLAS is only the third known object found in the solar system after entering from interstellar space (the others being 1I/'Oumuamua, seen in 2017, and 2I/Borisov, detected in 2019) means that it is still an object of great fascination, albeit a natural one.

"We all would have been thrilled to find technosignatures coming from 3I/ATLAS, but they're just not there," lead researcher Benjamin Jacobson-Bell from the University of California, Berkeley, told Space.com. "Finding no signals was the result we expected, due to the significant evidence for 3I/ATLAS being a comet with only natural features.

"The evidence was against 3I/ATLAS being one such probe, but we would have been remiss not to check."

Jacobson-Bell explained that scientists have even discussed conducting this exact kind of exploration using probes of our own. An example of this is the Breakthrough Starshot initiative, a concept that proposes to launch thousands of extremely lightweight probes toward Alpha Centauri, the nearest star system to our sun.

"There are compelling reasons to think a spacefaring species would send probes to other star systems as a way to learn more about their stellar neighborhood," Jacobson-Bell added.

Tuning in to radio 3I/ATLAS

The team behind this research theorized that if we find them, the brightest extraterrestrial technosignatures are likely to be narrowband radio signals, because these take comparatively little energy to produce and travel well over long distances.

"Breakthrough Listen searches for life beyond Earth in a variety of ways. The Green Bank Telescope is a radio dish 100 meters wide, situated in a zone federally regulated to be free of most radio interference," Jacobson-Bell said. "Its sensitivity enables us to verify the absence of transmitters down to 0.1 watts, the strongest evidence against technology of any 3I/ATLAS observation to date."

For comparison, modern cell phones typically emit radio waves at roughly the 1-watt level.

"This is to say that if there were any transmitters on 3I/ATLAS up to ten times weaker than a cell phone, we would have found them," Jacobson-Bell continued.

"Humans produce a lot of narrowband radio signals, including for communication with our own spacecraft," Jacobson-Bell said. "However, by modeling our search strategy on human technological output, we end up detecting a lot of human-made signals! Therefore, we run any detections through filters to distinguish probable human-made interference from possible extraterrestrial signals."

The Green Bank Telescope covers a very broad range of radio frequencies, meaning the team is unlikely to have missed any signals purely because they were looking in the wrong part of the electromagnetic spectrum.

"We did find nine 'events,' which is our term for signals that pass certain filters in our search strategy, but on closer inspection, we could readily attribute all nine of them to known radio transmitters here on Earth," Jacobson-Bell said. It's very common to find, then discard, false alarms like this.

"Past work has shown that 3I/ATLAS looks like a comet and behaves like a comet, and our observations show that, like a comet, 3I/ATLAS is not a source of technological signals. In the end, there were no surprises."

As Jacobson-Bell pointed out, this may be perhaps slightly disappointing, but it doesn't mean that 3I/ATLAS isn't still hugely scientifically significant.

"There is considerable excitement around 3I/ATLAS because it's only the third-ever discovery of an interstellar object within our solar system," he continued. "Sending spacecraft to other star systems could be very informative, so it's tempting to imagine that some interstellar objects might be intentional probes."

Jacobson-Bell believes that discoveries of interstellar objects are likely to become much more common as the recently completed Vera C. Rubin Observatory begins its 10-year-long Legacy Survey of Space and Time (LSST).

"Whereas each individual interstellar object is currently an anomaly, future surveys will amass such a population of interstellar objects that we'll start to be able to tell which are typical and which are actually anomalous," he said. "Some of these objects will merit follow-up observations — could their anomalies be due to technology?"

This new research and its findings regarding 3I/ATLAS thus pave a path toward answering that question.

"We hope our search helps dispel the idea that this object is artificial, but likewise we hope that public interest in interstellar objects remains strong — they're very interesting whether they're spacecraft or comets, and it's entirely possible that one day, one of them will indeed be transmitting technological signals," Jacobson-Bell concluded. "If we don't look, we'll never know."

The team's research is available as a pre-peer-reviewed paper on the repository site arXiv.

Scientists have detected several sugars essential for life in the samples brought back from asteroid Bennu, NASA announced on Tuesday (Dec. 2).

Analyzing pristine fragments of the asteroid delivered to Earth by NASA's OSIRIS-REx spacecraft in 2023, a team led by Yoshihiro Furukawa of Tohoku University in Japan found ribose, a crucial building block of RNA, and glucose, an energy-rich sugar used by nearly all life on Earth.

Although the researchers stress that these sugars are not evidence of life itself, their presence suggests that the basic chemical ingredients needed for biology were common throughout the early solar system.

"They were everywhere," Danny Glavin, an astrobiologist at NASA's Goddard Space Flight Center in Maryland and a co-investigator on the OSIRIS-REx mission, said in a NASA video announcing the finding.

If materials like these were widespread, he added, then places such as Mars or Jupiter's icy moon Europa may also have been seeded with the same raw ingredients. "I'm becoming much more optimistic that we may be able to find life beyond Earth, even in our own solar system."

Pristine extraterrestrial chemistry

Because the OSIRIS-REx spacecraft scooped and sealed the Bennu samples directly in space, the grains never touched Earth's environment. Scientists say that allowed them to study pristine extraterrestrial chemistry, something not possible with meteorites that crash to Earth and quickly become contaminated.

For the new study, published on Tuesday in the journal Nature Geoscience, Furukawa's team analyzed about 600 milligrams of powdered Bennu material. After soaking the grains in water and acid to extract any sugars, the scientists used highly sensitive lab instruments to detect chemical "fingerprints" matching ribose, glucose and several other sugars, according to the paper.

The researchers say the most exciting of these is ribose, a sugar that forms the backbone of RNA — a molecule that stores genetic information, helps build proteins, and carries out many of life's essential chemical reactions. The prevailing scientific consensus is that RNA arose before DNA in early life, making ribose a key piece in theories about how life began.

Furukawa's team also discovered glucose, the primary fuel source for modern life, marking the first time this sugar has been identified in an extraterrestrial sample.

"These sugars complete the inventory of ingredients crucial to life," Furukawa and his team wrote in the new paper.

The results suggest the sugars formed inside Bennu's long-lost parent asteroid more than 4.5 billion years ago, when pockets of salty water reacted with simple organic molecules inside the rock. That parent body later drifted into the inner solar system, broke apart in the asteroid belt, and eventually reassembled into the rubble-pile asteroid now known as Bennu.

The researchers also note that they did not detect a type of sugar used to build DNA, called 2-deoxyribose, whose absence supports the long-standing "RNA world" hypothesis that early life relied on RNA first, with DNA and proteins evolving later.

Scientists say they're now checking whether similar sugars appear in samples from Ryugu, a nearby asteroid sampled by Japan's Hayabusa2 mission. "I wouldn't be surprised if we found them there as well," Glavin said in the video.

More to come

The sugar detections were one of three major Bennu findings announced on Tuesday.

A second team, co-led by Zack Gainsforth of the University of California, reported discovering a type of "space gum" in the Bennu samples — an unusual, polymer-like material never before seen in space rocks.

"It was like nothing we had ever seen," Gainsforth said in a NASA statement. "For months we were consumed by data and theories as we attempted to understand just what it was and how it could have come into existence."

Once soft and flexible but now hardened, the substance forms tangled molecular chains rich in nitrogen and oxygen, according to the study, which was published in Nature Astronomy. Because it appears to have formed very early in the asteroid's history, scientists say it may be an early chemical precursor that helped set the stage for life on Earth, and perhaps one of the first alterations preserved inside Bennu.

A third study, led by Ann Nguyen of NASA's Johnson Space Center in Texas and also published in Nature Astronomy, found that Bennu contains six times more dust from ancient exploding stars than any other known space material. These fragile grains indicate that Bennu's parent body formed in a region of the early solar nebula enriched in dust of dying stars, scientists say.

"On this primitive asteroid that formed in the early days of the solar system, we're looking at events near the beginning of the beginning," Scott Sandford, an astrophysicist at the Ames Research Center in California, who co-led the analysis with Gainsforth, said in the NASA statement.

An Australian company wants to join efforts to study a rare space event, conducting its own flyby of the asteroid Apophis when it makes its close approach to Earth in 2029.

Sydney-based HEO Robotics, a provider of commercial satellite-to-satellite imagery, wants to add to the international missions already planning to get up close to the 1,115-foot-wide (340 meters) asteroid Apophis as it zooms by Earth in April 2029 by buying a satellite near the end of its life up in geostationary orbit and use its remaining fuel.

Satellites in the geostationary belt (GEO) orbit 22,236 miles (35,786 kilometers) above the equator. Spacecraft nearing the end of their lives use their remaining fuel to head into a so-called graveyard orbit above GEO to take themselves out of the way of the operational satellites. HEO aims to buy a satellite near the end of its mission lifetime and, using a little more fuel than needed for the graveyard trip, make a close approach to Apophis, which will pass within the GEO belt when it makes its close approach to Earth on Friday, April 13, 2029.

Despite being classified as a potentially hazardous asteroid, which will get within a mere 5.9 Earth radii of our planet, Apophis poses no threat on this close encounter. Rather, scientists regard the 2029 flyby as an opportunity, as an asteroid the size of Apophis passes this close to Earth on average just once every 7,500 years. The close approach thus offers a unique chance for close study of how an asteroid is influenced when flying by a planet.

HEO will be far from alone. NASA, the European Space Agency and Japan are all preparing their own missions (OSIRIS-APEX, RAMSES and DESTINY+, respectively) to get up close to Apophis before, during and after the unique flyby, which could potentially be seen by as many as 2 billion people. Other spacecraft, including a probe from China, may join.

The move is part of HEO’s plans to expand beyond providing non-Earth imagery in low Earth orbit and eventually provide images from across the solar system on demand.

"It's not even the easiest asteroid to go visit," Will Crowe, co-founder and chief executive of HEO, said of Apophis when speaking to Space.com at the International Astronautical Congress (IAC) in Sydney in early October. "I think there's just been a lack of imagination," Crowe added, stating that other asteroids will soon be in HEO’s sights.

"We're starting with just the ones that are coming through the Earth-moon system," he said. "But there's no reason why we can't enable it for everything — the asteroid belt or all the other weird asteroid classes. It should be possible."

NASA's OSIRIS-APEX spacecraft captured stunning new images of Earth recently as it whipped past the planet during a high-speed slingshot maneuver, sending the probe on a fast track toward the famous asteroid Apophis.

The photos showcase Earth in striking detail during a flyby on Sept. 23 when OSIRIS-APEX — short for "Origins, Spectral Interpretation, Resource Identification and Security-Apophis Explorer" — flew just 2,136 miles (3,438 kilometers) above the planet during its closest approach.

The spacecraft captured swirling clouds over Earth's blue oceans and glimpses of continents passing below. The following day, as it departed Earth, OSIRIS-APEX snapped a dramatic shot of the moon opposite Earth from roughly 370,000 miles (595,000 kilometers), according to a statement from NASA.

OSIRIS-APEX is the second phase of OSIRIS-REx, the mission that returned a sample from the near-asteroid (NEA) Bennu in 2023. After that historic journey, NASA charted a new course toward Apophis, a stony metal-rich NEA that offers a sharp scientific contrast to Bennu's carbon-rich composition (and was once thought to pose a serious impact risk to Earth). The recent images from OSIRIS-APEX mark an early milestone, confirming that its cameras and instruments are fully operational after years in deep space, and that the spacecraft is on course for its interplanetary journey.

The September flyby was designed to use Earth's gravity to boost OSIRIS-APEX's speed and redirect it toward Apophis, which will swing past Earth on April 13, 2029. That encounter will bring the asteroid closer than many satellites — close enough for Earth's tidal forces to potentially reshape the asteroid's surface, alter its spin or even shift its orbit. OSIRIS-APEX is scheduled to arrive shortly thereafter, making it the first mission to document how an asteroid responds to a close planetary pass, according to the University of Arizona's mission overview page.

Once in orbit around Apophis, the spacecraft will spend roughly 18 months mapping the asteroid, studying its composition and capturing high-resolution imagery. Mission planners also hope to hover a few meters above the surface and fire the probe's thrusters downward to stir up dust and reveal fresh previously hidden material.

The newly released Earth images were captured using the spacecraft's MapCam imager, which features red, green and blue filters, as well as StowCam, which is capable of both still and video imagery to verify safe storage of collected asteroid samples.

As the mission continues, OSIRIS-APEX will send back trajectory updates, perform additional instrument checks and eventually deliver the first up-close views of Apophis — a near-Earth asteroid whose close encounter with our planet could teach scientists more about how such bodies evolve and respond to gravitational forces.

NEW YORK — The American Museum of Natural History (AMNH) in New York City has opened a new exhibition that takes a multidisciplinary perspective on the asteroid strike that ended the Cretaceous period and killed all the non-avian dinosaurs. The exhibit — aptly called "Impact" — chronicles what was, in the words of AMNH curator of paleontology Roger Benson, Earth’s "worst day of the last half-billion years."

One spring day 66 million years ago, a rock from outer space slammed into what is now the Yucatan Peninsula. The meteor was roughly the size of Mount Everest, and it struck with the force of 10 billion atomic bombs. Nearby forests instantly incinerated as atmospheric temperatures briefly soared to 500 degrees Fahrenheit. Many animals, including large dinosaurs, were buried in ash — though some were able to escape by digging underground or diving underwater.

The tremendous impact also flung a mushroom cloud of ash and dust into the atmosphere, eventually shrouding the planet in a cold gloom. Tiny glass beads rained down as far away as Wyoming. At the same time, the impact triggered landslides, earthquakes and tsunamis around the world.

A little backstory

The scene was nothing short of apocalyptic. "It sounds like science fiction or the stuff of Hollywood movies," Benson told a small crowd of reporters at a preview press event. But piecing together the story of this violent end to the age of dinosaurs has been a centuries-long, interdisciplinary process.

The first hint that something strange happened at the end of the Cretaceous period was the K-Pg boundary layer, a dark stripe of clay in the sedimentary rock record above which dinosaur fossils are absent. This layer was first recognized by geologists in the late 1700s and early 1800s. However, its exact cause — and geologic significance — remained a mystery until the 1980s. Only then did planetary scientist Walter Alvarez and his father, physicist Louis Alvarez, discover the K-Pg boundary layer contained an astonishingly high concentration of iridium, an element that is scarce on Earth's surface but abundant in space rocks. The only plausible explanation? Our planet was struck by an asteroid millions of years ago.

It was a decisive blow to another popular scientific theory at the time — the concept of gradualism, which holds that geological and evolutionary changes only unfold slowly and over long periods of time. "It represented a paradigmatic shift in people’s thinking," Neil Landman, a curator of fossil invertebrates at AMNH, told Space.com.

Since then, researchers from every corner of science have helped piece together our current understanding of the event. Meteorite experts pinpointed the impact site: the Chicxulub crater in Mexico. Invertebrate paleontologists identified widespread ocean acidification based on the mass deaths of tiny creatures called foraminifera. And evolutionary biologists and paleobotanists detailed life's recovery through the fossil record.

"It's been a tremendous coalescence of ideas," Denton Ebel, a meteorite expert at AMNH, told Space.com.

The walkthrough

The exhibit walks guests through the event as it unfolded chronologically. First, visitors encounter panoramas depicting life at the end of the Cretaceous. In one, a massive mosasaur hunts a long-necked plesiosaur, both members of marine reptile lineages that died out after the asteroid impact. Across the way, a triceratops lumbers through a prehistoric forest alongside turtles, primitive mammals, small dinosaurs and toothed birds.

Then, visitors move into a small theater to watch a 6-minute video detailing the damage wrought by the meteor strike. Finally, the exhibit highlights the aftermath of the destruction, showing life's slow recovery and how new organisms, like mammals, moved in to fill the niches left by the dinosaurs’ extinction.

Ultimately, Benson said he hopes guests leave with a sense of life's ephemerality, as well as its resilience. We are currently living through another mass extinction, one less acute than the end of the Cretaceous, but potentially no less deadly. This time, however, humanity is the asteroid — and we have a chance to change our impact.

"We live on a changing planet," said Benson. "Rates of species extinction over the last 100 years or may be comparable to those that occurred during mass extinction events of the past. But we still have time."

The exhibit opened to the public on Nov. 17.

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

A sizable asteroid impact generally obliterates anything alive nearby. But the aftermath of such a cataclysm can actually function like an incubator for life. Researchers studying a Finnish impact structure found minerals whose chemistry implies that microbes were present roughly 4 million years after the impact. These findings, which were published in Nature Communications last month, shed light on how rapidly microscopic life colonizes a site after an asteroid impact.

A special lake

Finland is known for its myriad lakes used by boaters, fishers, swimmers, and other outdoor afficionados. Lake Lappajärvi is a particularly special Finnish lake with a storied past: Its basin was created roughly 78 million years ago when an asteroid slammed into the planet. In 2024, the United Nations Educational, Scientific and Cultural Organization (UNESCO) established a geopark in South Ostrobothnia, Finland, dedicated to preserving and sharing the history of the 23-kilometer-diameter lake and the surrounding region.

Jacob Gustafsson, a geoscientist at Linnaeus University in Kalmar, Sweden, and his colleagues recently analyzed a collection of rocks unearthed from deep beneath Lake Lappajärvi. The team’s goal was to better understand how rapidly microbial life colonized the site after the sterilizing impact, which heated the surrounding rock to around 2,000°C (3,632°F).

There’s an analogue between this type of work and studies of the origin of life, said Henrik Drake, a geochemist at Linnaeus University and a member of the team. That’s because a fresh impact site contains a slew of temperature and chemical gradients and no shortage of shattered rocks with nooks and crannies for tiny life-forms. A similar environment beyond Earth would be a logical place for life to arise, Drake said. “It’s one of the places where you think that life could have started.”

Microbe-Sculpted Minerals

In 2022, Gustafsson and his collaborators traveled to Finland to visit the National Drill Core Archive of the Geological Survey of Finland.

There, in the rural municipality of Loppi, the team pored over sections of cores drilled from beneath Lake Lappajärvi in the 1980s and 1990s. The researchers selected 33 intervals of core that were fractured or shot through with holes. The goal was to find calcite or pyrite crystals that had formed in those interstices as they were washed with mineral-rich fluids.

The team used tweezers to pick out individual calcite and pyrite crystals from the cores. Gustafsson and his collaborators then estimated the ages of those crystals using uranium-lead dating and a technique known as secondary ion mass spectrometry to calculate the ratios of various carbon, oxygen, and sulfur isotopes within them. Because microbes preferentially take up certain isotopes, measuring the isotopic ratios preserved in minerals can reveal the presence of long-ago microbial activity and even identify types of microbes. “We see the products of the microbial process,” Drake said.

“It’s amazing what we can find out in tiny crystals,” Gustafsson added.

The researchers also used isotopic ratios of carbon, oxygen, and sulfur to estimate local groundwater temperatures in the distant past. By combining their age and temperature estimates, the team could trace how the Lake Lappajärvi impact site cooled over time.

A slow cool

Groundwater temperatures at Lake Lappajärvi had cooled to around 50°C (122°F) roughly 4 million years after the impact, the team found. That’s a far slower cooling rate than has been inferred for other similarly sized impact craters, such as Ries Crater in Germany, in which hydrothermal activity ceased after about 250,000 years, and Haughton Crater in Canada, where such activity lasted only about 50,000 years.

“Four million years is a very long time,” said Teemu Öhman, an impact geologist at the Impact Crater Lake–Lappajärvi UNESCO Global Geopark in South Ostrobothnia, Finland, not involved in the research. “If you compare Lappajärvi with Ries or Haughton, which are the same size, they cooled way, way, way faster.”

That difference is likely due to the type of rocks that predominate at the Lappajärvi impact site, Gustafsson and his collaborators proposed. For starters, there’s only a relatively thin layer of sedimentary rock at the surface. “Sedimentary rocks often don’t fully melt during impact because of their inherent water and carbon dioxide content,” Drake explained. And Lappajärvi has a thick layer of bedrock (including granites and gneisses), which would have melted in the impact, sending temperatures surging to around 2,000°C, earlier research estimated.

About 4 million years after the impact is also when microbial activity in the crater began, according to Gustafsson and his collaborators. Those ancient microbes were likely converting sulfate into sulfide, the team proposed. And roughly 10 million years later, when temperatures had fallen to around 30°C (86°F), methane-producing microbes appeared, the researchers surmised on the basis of their isotopic analysis of calcite.

In the future, Gustafsson and his colleagues plan to study other Finnish impact craters and look for similar microbial features in smaller and older impact structures. In the meantime, the team is carefully packaging up their material from the Lappajärvi site. It’s time to return the core samples to the Geological Survey of Finland, Drake said. “Now we need to ship them back.”

An Ontario preteen may be one of the youngest Canadians to ever find an asteroid.

Siddharth Patel, a 12-year-old who lives in London, Ontario (west of Toronto), spotted two possible asteroids in September as part of a citizen science program that partners with NASA, according to the Toronto Star.

The two suspected space rocks are called 2024 RX69 and 2024 RH39 and are cataloged in the Minor Planet Center, which is a branch of the International Astronomical Union that reports and tracks asteroids and other small, naturally occurring space objects.

Siddharth told the Star he pursues his love of astronomy — he's been using a telescope since age five, supported by parents with no space background — after finishing school activities.

"Space was not really taught in schools," he said. "I really started doing things about space after I came back from school, because school is the academic time. And after that is the time when I pursue my interests and dreams."

While confirming the asteroids' orbits may take as long as a decade, Patel has another big project on his mind: becoming an astronaut. He recently joined the youth-focused Royal Canadian Air Cadets to learn how to fly a plane, the Star reported. This is following the pathway of notable Canadian Space Agency astronauts such as Jeremy Hansen (who will fly around the moon as part of NASA's Artemis 2 mission next year) and Chris Hadfield, the first Canadian to command the International Space Station.

Siddharth found the asteroids through the International Astronomical Search Collaboration, which uses images from the Hawaiian Pan-STARRS facility and the Arizona-based Catalina Sky Survey for asteroid searches. While Siddharth's two space rocks reside in the main asteroid belt between Mars and Jupiter, the collaboration can also find near-Earth asteroids and trans-Neptunian objects (which orbit the sun beyond Neptune), according to NASA.

The provisional asteroid discoveries aren't Siddharth's only space accolades. His image of Comet C/2023 A3 (Tsuchinshan-ATLAS) alongside the Milky Way received the People's Choice Award in DarkSky International's 2025 Capture the Dark photography contest.

"I love taking photos through my telescopes," Siddharth told the Canadian Broadcasting Corp. "When I go to somewhere dark, or someplace that has lots of stars, it really ignites my sense of wonder. I've learned how mysterious space really is."

A newly found interstellar comet poses absolutely no threat to Earth, but a NASA-coordinated group plans to observe it to help our ability to monitor any future objects that might prove to be hazardous.

The comet, called 3I/ATLAS, is the third known interstellar object that has come through our solar system. As it flies deeper into the solar system before leaving our cosmic neighborhood some time between Nov. 27, 2025 and Jan. 27, 2026, the International Asteroid Warning Network is kicking off a campaign to observe the comet.

The project will serve as a training ground to not only predict the orbit of 3I/ATLAS, but to perform astrometric measurements (meaning, tracking the comet's speed and motion in Earth's sky, relative to objects like stars.) This will be used to inform future observations of comets or asteroids that may be a threat to Earth.

The network notes that comets are especially hard to observe, because their tails and "atmospheres" (comas) make it difficult to estimate overall brightness — which in turn affects pathway predictions.

Knowing the pathway of an object allows astronomers to predict how close it will come to Earth. In this case, 3I/ATLAS is coming nowhere near us. But its relative proximity (roughly 1.8 astronomical units, or sun-Earth distances, at its closest) is good enough for observations by small telescopes.

"The campaign will target comet 3I/ATLAS (C/2025 N1) to exercise the capability of the observing community to extract accurate astrometry," read a notice of the project Tuesday (Oct. 21) at the Minor Planet Center, which is a branch of the International Astronomical Union that catalogs and tracks small objects in space.

Citizen scientists are welcome to join in. If you're interested, register at this link no later than Nov. 7—as the notice provides no time of day, we recommend registering as soon as feasible. The schedule includes a workshop on Nov. 10, and periodic teleconferences through and after the observing period.

The International Asteroid Warning Network calls itself a "worldwide collaboration of asteroid astronomers and modelers" and was formed following recommendations from the United Nations and its space mission planning advisory group "for an international response to the near-Earth object (NEO) impact threat."

NASA, like other parts of the U.S. government, is allowed to perform essential duties despite the ongoing government shutdown. Comet and asteroid observations are considered a priority item as there is a small chance one could pose a threat to Earth, so NASA continues to track and publish information about them.

The agency has undertaken decades of searching to see if there are any potentially hazardous objects threatening our planet. Despite dedicated examinations of the sky, no imminent threats have been found. But NASA and its network of partner telescopes continue the search — just in case.

A newly found space rock almost broke a speed record.

The asteroid, called 2025 SC79, has a pathway within the orbit of Venus that zips around the sun in only 128 days, making it the second-fastest unique asteroid orbit in the solar system, according to a statement from Carnegie Science. 2025 SC79 is also a pretty big asteroid: roughly 0.4 miles (700 meters) long, or roughly the length of a skyscraper.

Carnegie astronomer Scott Sheppard, a noted discoverer of small moons around Jupiter, Saturn, Uranus and Neptune, spotted the asteroid on Sept. 27 hiding in the sun's glare. While 2025 SC79 will make no close approaches to Earth for the foreseeable future, finding hidden asteroids is essential for protecting our planet, Sheppard emphasized in the statement. "The most dangerous asteroids are the most difficult to detect," Sheppard said. "Most asteroid research finds these objects in the dark of night, where they are easiest to spot. But asteroids that lurk near the sun can only be observed during twilight—when the sun is just about to rise or set. If these 'twilight' asteroids approach Earth, they could pose serious impact hazards."

Sheppard and his team also previously found the fastest-known asteroid, 2021 PH27, which circles the sun in only 113 days — less than a third of a year on Earth. His research into twilight asteroids, which includes financial support from NASA, uses the Dark Energy Camera at the National Science Foundation's (NSF) Víctor M. Blanco 4-meter telescope in Chile.

The new asteroid was confirmed by NSF's Gemini Observatory (which has locations in Hawaii and Chile) as well as Carnegie Science's twin Magellan Telescopes in Chile. News of 2025 SC79's discovery was brought to the astronomy community Oct. 15 in a circular from the Minor Planet Center, a branch of the International Astronomical Union that shares information on small, natural bodies in space.

Follow-up observations of 2025 SC79 will need to wait several months as it is now behind the sun, from Earth's perspective. "Future research of this object will reveal details about its composition—and how it survives the intense heat of its proximity to the Sun—as well as its possible origin," Carnegie officials stated.

Sheppard added following up observations of this type of asteroid has a lot of merit, because it helps astronomers understand how perturbations in small-body orbits, caused by gravity of other objects like planets, can make the pathway veer over the eons. "Understanding how they [asteroids] arrived at these locations can help us protect our planet, and also help us learn more about solar system history."

Astronomers keep close watch on asteroids in the sky, including "potentially hazardous" asteroids that in the statistical sense, are deemed a little more worrisome. After decades of careful searching, however, no imminent threats to our planet have been found.

NASA and a network of telescopes keep searching just in case—with the work being deemed so essential that findings continue to be published this month despite the ongoing U.S. government shutdown.

A newly discovered space rock zoomed safely by Earth on Wednesday (Oct. 15) at only about a quarter of the average distance to the moon.

The asteroid, called 2025 TP5, sailed by our planet at 4:09 p.m. EDT (2009 UTC) at a minimum distance of 60,328 miles (97,089 km), according to data from NASA's Jet Propulsion Laboratory. (NASA is in shutdown, like much of the U.S. government, but critical activities like seeking potentially hazardous asteroids can continue.) By comparison, the average distance to the moon is 238,855 miles (384,400 kilometers).

After passing by Earth, 2025 TP5 will make a close flyby of the moon on Thursday (Oct. 16), flying as close to the lunar surface as 74,616 miles (120,084 km), JPL stated. It's a moderately sized asteroid: with an estimated diameter of around 54 feet (16 meters), according to JPL, 2025 TP5 is about the same scale as the six-story Chelyabinsk meteor that broke up above Russia in 2013.

Despite 2025 TP5 coming relatively close to Earth in September 1979, astronomers only discovered the space rock Tuesday (Oct. 13) around 4:07 a.m. EDT (0807 UTC) using the Asteroid Terrestrial-impact Last Alert System (ATLAS), at a facility in Mauna Kea, Hawaii. Astronomers there were the first to post observations to a circular about 2025 TP5 shared by the Minor Planet Center, which is a branch of the International Astronomical Union that brings new discoveries to the community.

ATLAS is a four-telescope, early-warning system for asteroids developed by the University of Hawaii and funded by NASA, according to the ATLAS website. While its design is to seek potentially hazardous asteroids, this particular one was not a threat.

Astronomers have spent several decades cataloging asteroids of a threatening size that may be intersecting Earth, and have found no imminent threats to our planets after decades of searching. Indeed, the technology has improved so much that it’s common to find several small asteroids coming close to Earth every month, including one earlier this October that skimmed above us at the altitude of the International Space Station.

When it comes to saving Earth from a potential doomsday rock, knowing where to hit it and how it spins could make all the difference. Two new studies presented last month at the Europlanet Science Congress in Helsinki may have just given scientists both answers.

In one study, researchers led by Wen-Han Zhou of the University of Tokyo used data from the European Space Agency's now-retired Gaia mission to study how an asteroid's spin depends on how often it's been hit by other space rocks. In another study, a team led by Rahil Makadia of the University of Illinois at Urbana-Champaign developed a method for identifying the safest regions on an asteroid to strike with a deflection mission, without accidentally steering it back toward Earth.

Together, the findings offer a new way to understand the structure and behavior of these ancient bodies — knowledge that could prove critical to deflecting a dangerous asteroid if it were ever on a collision course with our planet.

"By leveraging Gaia's unique dataset, advanced modelling and AI tools, we've revealed the hidden physics shaping asteroid rotation, and opened a new window into the interiors of these ancient worlds," Zhou said in a statement.

How asteroids get their spin

In recent decades, astronomers have been puzzled by why some asteroids rotate like spinning tops while others tumble through space in chaotic, unpredictable ways. Zhou's team set out to solve that mystery using Gaia's vast archive of asteroid light patterns and new computer models.

Their analysis showed that an asteroid's spin pattern boils down to a cosmic "tug of war" between two forces: collisions that knock them into unstable motion and internal friction that gradually smooths their rotation.

"When these two effects balance, they create a natural dividing line in the asteroid population," Zhou said in the statement.

Machine learning revealed this "dividing line" in Gaia's data as a clear gap between fast-spinning asteroids and slow, tumbling ones. Slower rotators, the researchers found, are more easily jolted into a wobble by impacts, while faster ones resist those disturbances, according to the statement.

Sunlight also plays a subtle but important role, the study reports. As an asteroid's surface heats up during the day and cools at night, it emits tiny bursts of radiation that act like microscopic thrusts. For smoothly spinning asteroids, those pushes line up in the same direction and gradually change their spin rate. But for tumblers, the pushes more or less cancel each other out, trapping them in their slow, chaotic motion.

The results also indicate that many asteroids aren't solid chunks of rock, but loose clusters of rock and dust held together weakly by gravity, known to astronomers as "rubble piles." That distinction matters for planetary defense, scientists say, because a fragile, porous asteroid would react to a spacecraft's impact very differently than a dense, solid one.

As more sky surveys come online, scientists will be able to apply this method to much larger samples, Zhou said in the statement. With upcoming observatories such as the Vera C. Rubin Observatory's Legacy Survey of Space and Time, "we'll be able to apply this method to millions more asteroids, refining our understanding of their evolution and make-up."

Finding the safe spots to strike

If knowing how an asteroid spins is the first step, the next is figuring out where to hit it.

Makadia's team investigated what happens when a spacecraft slams into an asteroid, and found that not all impact sites are created equal. Striking the wrong spot could send an asteroid drifting into what scientists call a gravitational keyhole — a tiny region of space where a planet's gravity could subtly bend the asteroid's orbit and make it swing back toward Earth on a future pass decades or centuries later.

"Even if we intentionally push an asteroid away from Earth with a space mission, we must make sure it doesn't drift into one of these keyholes afterwards," Makadia said in a different statement. "Otherwise, we'd be facing the same impact threat again down the line."

To avoid such a cosmic boomerang effect, Makadia's team created probability maps of asteroid surfaces that could guide mission planners. Using lessons from NASA's DART mission, which slammed into the asteroid Dimorphos in September 2022, and realistic spacecraft trajectories, they simulated hundreds of millions of kinetic-impact missions, each varying slightly in speed, angle and timing.

For each simulation, they calculated how an asteroid's motion would change, and whether it might drift into one of these gravitational keyholes. Repeating this process for a range of impact points and rotation angles allowed them to pinpoint the safest and most effective strike zones, according to the second statement.

"With these probability maps, we can push asteroids away while preventing them from returning on an impact trajectory, protecting the Earth in the long run," said Makadia.

To test their model, the researchers applied it to the near-Earth asteroid Bennu, one of the best-studied near-Earth objects thanks to NASA's OSIRIS-REx mission, which precisely mapped its surface, studied its orbit and brought a sample of the space rock home to Earth.

Earlier models had shown that Bennu's path included several potential gravitational keyholes that could, in theory, redirect it toward Earth sometime in the 22nd century. But data from OSIRIS-REx dramatically reduced those uncertainties, ruling out many potential keyholes and future impact scenarios.

Using that precise orbital data, Makadia's team simulated spacecraft impacts under a variety of conditions and projected Bennu's potential keyhole encounters, creating detailed impact-probability maps.

These maps show which areas on an asteroid would make the safest targets, and which regions could increase the long-term risk of a future encounter, the study notes. The optimal strike zones, marked as bright crosshairs in the model, show where a spacecraft could nudge an asteroid's orbit away from Earth without triggering a dangerous return later on.

According to the study, this kind of analysis could help design safer deflection missions even using only ground-based observations, when time doesn't allow for a dedicated rendezvous spacecraft.

"Fortunately, this entire analysis, at least at a preliminary level, is possible using ground-based observations alone, although a rendezvous mission is preferred," Makadia said in the statement.

As next-generation telescopes and missions uncover millions more asteroids, studies like these are helping scientists write a planetary defense blueprint to safeguard Earth.