NASA's Hubble Space Telescope has discovered that a system of asteroids in the distant Kuiper Belt may be triplets, not twins as previously suspected.

If so, the stable trio of icy space rocks would be just the second example of three gravitationally bound space rocks found in the Kuiper Belt, the doughnut-shaped region of icy bodies that lurks out beyond the orbit of Neptune.

The discovery could also challenge our understanding of how Kuiper Belt objects (KBOs) form.

If it is confirmed as a triplet, the system — designated 148780 Altjira — could offer scientists a chance to improve their models of how three gravitationally bound bodies move through space together.

This puzzle, known as the "three-body problem," has been a challenge since Isaac Newton published his work "Principia" in 1687.

"The universe is filled with a range of three-body systems, including the closest stars to Earth, the Alpha Centauri star system, and we're finding that the Kuiper Belt may be no exception," team leader Maia Nelsen, a physics and astronomy graduate of Brigham Young University in Provo, Utah, said in a statement.

Related: What is the Kuiper Belt?

Three's company in the Kuiper Belt

Astronomers Dave Jewitt and Jane Luu discovered the first icy body in the Kuiper Belt, known as 1992 QB1, in 1992. Since then, a further 3,000 KBOs have been cataloged.

Astronomers estimate that several hundred thousand more KBOs measuring over 10 miles (16 kilometers) in diameter could lurk in this icy donut, which begins around 2.8 billion miles (4.5 billion km) from the sun.

The Kuiper Belt is thought to stretch as far as 4.6 billion miles (7.4 billion km) from the sun, which is around 50 times the distance between Earth and our star. The Altjira system sits in the middle of the Kuiper Belt, at around 3.7 billion miles (6.0 billion km) from the sun, or about 40 times the distance between Earth and the sun.

The Hubble Space Telescope images initially seemed to show that the Altjira system was composed of two KBOs located about 4,700 miles (7,600 km) apart.

When the team conducted repeated observations of the Altjira system object's unique co-orbital motion, however, they found the inner object is actually two bodies. These KBOs are so close together that they can't be distinguished individually from such a great distance away.

"With objects this small and far away, the separation between the two inner members of the system is a fraction of a pixel on Hubble's camera, so you have to use non-imaging methods to discover that it's a triple," Nelsen said.

It took 17 years of data from Hubble and the Keck Observatory in Hawaii to observe orbital changes in the Altjira system and make this determination. The data was added to various modeling scenarios, with the most likely explanation being a triple-body system.

"Other possibilities are that the inner object is a contact binary, where two separate bodies become so close they touch each other, or something that actually is oddly flat, like a pancake," Nelsen added.

Of 40 multiple-body systems identified in the Kuiper Belt, this is just the second identified composed of more than two objects. The researchers think these aren't outliers and there are more multi-asteroid systems out there in the outer reaches of the solar system, waiting to be discovered,

The Hubble observations of the Altjira system, which suggest it has a third occupant, support a theory of KBO creation that involves the direct gravitational collapse of matter in the disk of material surrounding the infant sun around 4.5 billion years ago.

This direct collapse pathway is similar to the formation process of stars, albeit it on a vastly smaller scale. Star formation from dense patches of gas and dust can also result in two and three-body systems.

The alternative KBO creation theory, which sees these icy space rocks created from collisions between larger bodies, would not create a three-body arrangement as the Altjira system appears to be.

The Altjira system joins the dwarf planet Pluto and the "space snowman" Arrokoth, a contact binary composed of two touching space rocks, as the most heavily studied bodies in the Kuiper Belt.

NASA's New Horizons probe flew by Pluto in 2015 and Arrokoth in 2019. There's no visit to Altjira in the works, but the researchers behind the new study hope that detailed remote observations of the system will be possible in the future.

Particularly exciting will be forthcoming observations of Altjira conducted by the James Webb Space Telescope during its third year of operations.

"Altjira has entered an eclipsing season, where the outer body passes in front of the central body," Nelsen said. "This will last for the next 10 years, giving scientists a great opportunity to learn more about it." \

The new study was published on Tuesday (March 4) in The Planetary Science Journal.

North America's total solar eclipse on April 8 comes just after spring break, but where kids will be depends on where you live. Some schools are closing for the eclipse for safety reasons, while others are doing so because the eclipse coincides with the end of the school day. 

Either way, the stakes are high. "Every adult has a few childhood memories that stand out vividly from the blur that becomes our history," said Debra Ross, publisher of KidsOutAndAbout.com, Chair of both the Rochester Task Force for Eclipse 2024 and Co-chair of the AAS Solar Eclipse Task Force, to Space.com. "The upcoming eclipse presents a once-in-a-childhood opportunity for parents to help shape a lifelong memory for their kids and create a vivid bond with them that will resonate into their future."

NASA's Jet Propulsion Laboratory has also put together a great list of teaching tools and activities designed to educate and inspire young minds. You can view some of their eclipse-specific learning materials on their website. 

Before: learn about the eclipse

If you prepare kids well for what is about to happen, they will get more from it. "In advance of eclipse day, help your kids learn the basic science of what will be happening and what they will see during the partial and total phases," said Ross. A good place to start is What Will the Eclipse Look Like from My City? for useful simulations by eclipse expert Dan McGlaun of Eclipse2024.org. Also handy is Timeanddate, which will give you an exact schedule of what will happen, when, and what to look out for for any location. 

Before: make a space-themed buffet

A space-themed buffet is a fun way to celebrate the big day, and it's hardly a challenging task for kids during a trip to a store. Chocolate MoonPie marshmallow sandwiches, Mars bars, Milky Ways and Little Debbie Cosmic Brownies are a given, as are Starburst, Sun Chips, SunnyD and Capri-Sun. 

Although a space-themed buffet is just for fun, there is a way of using Oreos as a learning opportunity. Forget the new flavors of Oreos, such as chocolate creme, and go for a pack of originals. That way, you can separate each one and create a montage of the stages of a solar eclipse, laying the dark biscuit (the moon) across the white cream on the other biscuit (the sun) to create a more and more obscured sun.  

Before: create eclipse-viewing masks

Making and decorating eclipse glasses is a fun and creative way to get kids excited about the eclipse. Using any pair of solar eclipse glasses as the centerpiece, create almost any thing you want to go around them. The easiest way is to combine a paper plate with some eclipse glasses, which is also a good way of protecting skin against the sun while outside for several hours (though that may not be a significant issue in April). Decorate the plates with markers, stickers, or paint.

Before: make a pinhole camera

If you can't get hold of eclipse glasses, the best way to view the partial phases of any solar eclipse is through a pinhole camera, which produces an image of the sun on a screen. It's easy to make from things you can find around your home — a shoebox, tinfoil, a sheet of paper, tape, a pin or needle and a box cutter. Our sister site, Live Science, explains how. You'll want to start this a few hours before the eclipse's partial phases begin.

Before: make pinhole cards

Any regular-sized hole will project an image of an eclipsed sun onto any surface below it. Colanders work well. So do spaghetti spoons. But so does anything created using a hole punch. So, get kids to write their names using a series of holes, and they can project crescent suns through them. A photo can make an excellent souvenir memory of the day. "If you don't have eclipse glasses, you can make a pinhole camera or use a button, colander, RITZ cracker, or your own two hands," said Janet Ivey-Duensing, CEO and Founder of Janet's Planet. "Place one hand on top of the other and let the sun shine through your fingers onto a white piece of paper, and you will see mini-reflections of the eclipse."

During: wear eclipse glasses

These are, of course, essential during the partial phases of the eclipse. 

"Teach your kids when and when not to wear their eclipse glasses — any time one looks at the sun, including during the partial phases," said Ross. "But also when not to — you must remove them during totality, or you'll miss seeing the sun's corona." The latter only applies to those in the path of totality.

NASA gives some excellent advice on its website about how to use eclipse glasses, which is worth practicing with kids: "Stand still and cover your eyes with your eclipse glasses or solar viewer before looking up at the bright sun. After looking at the sun, turn away and remove your filter — do not remove it while looking at the sun."

During: talk about totality

Eclipse chasers fixate on seeing the totally eclipsed sun. The sight of the sun's corona is undeniably the highlight for many who travel to the path of totality, but it's not just a visual experience. If you're on the path of totality, prime kids for the scope and scale of what they're about to experience. "Immediately before totality, remind kids that people process the world with their eyes, ears, skin, and emotions," said Ross. "Let them know that afterward, you'll be all talking about what you saw, heard, and felt inside and outside." This will help them focus on all of their senses separately and give them more to notice during totality, says Ross.

After: capture the emotion

As soon as totality ends, there's a rush of adrenalin and emotion as you all collectively try to put into words what you just experienced. Few people can resist the temptation to take photos of the eclipse with their smartphone. Still, it's videos taken just after totality that best capture the emotion of the occasion for posterity. "If you're with a group of friends or family, have someone video people's reactions after totality using a smartphone," said Alan Dyer, solar eclipse photographer and author of How to photograph the solar eclipse, in an interview with Space.com. He recommends assigning the task to kids. "Fresh reactions right after the eclipse are priceless and come before people have had the chance to think about it."

After: start a discussion

A great way to do this in a group of kids is to ask the right questions, preferably on camera (though it's the audio recording that's most precious years later. "Everyone will be talking excitedly anyway, so focus the discussion with questions like What did you see? What did you hear? What did you feel?" says Ross. 

Dark energy, the mysterious entity that dominates the energy of the cosmos and appears to be accelerating the expansion of the universe, presents a cosmic conundrum for scientists. 

In short, cosmologists have no idea what dark energy really is. So they are concocting all sorts of possible models, and exploring the observational consequences of those models, in hopes of finding some clue as to what dark energy is and how it works.

Now, new research suggests that we may have already found evidence of an evolving, dynamic kind of dark energy, in the form of the radiation emitted when the first stars appeared in the universe.

Billions of years ago, the universe was much darker than it is today. It took time for the first stars and galaxies to coalesce and appear, and when they did, they completely transformed the cosmos.

Related: The history of the universe from Big Bang to now in 10 steps

Prior to the formation of the first stars, the universe was dominated by a thin fog of neutral hydrogen and helium gas. That gas had formed during the momentous epoch known as recombination, a stage that occurred when our universe was 380,000 years old and had cooled to the point where the hot plasma could become neutral — when electrons could finally bind to nuclei to form the first atoms.

When the first stars ignited, however, their intense radiation ripped through the neutral gas, turning it back into a plasma state. And so cosmologists named the appearance of the first stars the "Cosmic Dawn" and the subsequent dramatic phase change of the universe the "Epoch of Reionization." These events occurred around a few hundred million years after the Big Bang.

We do not yet have any direct measurements or maps of the cosmological epoch when the first stars and galaxies formed, or of the Epoch of Reionization. The main challenge is that these events occurred an extremely long time ago, so the light from those first stars is incredibly weak.

An open window

But there is another window into the Epoch of Reionization. Neutral hydrogen emits radiation at an extremely specific wavelength: 21 centimeters (8.3 inches). This is not a strong signal at all, but there was a whole lot of neutral hydrogen back in the day. But that radiation was emitted billions of years ago, and in the intervening ages, the universe has expanded to be about 10 times its previous size. That expansion has stretched the wavelength of that 21-cm radiation, and today, it's now detectable in radio wavelengths.

In 2018, a team of astronomers claimed to have detected the 21-cm signal emitted when the universe was only 230 million years old. But the signal from that radiation was more than twice as strong as theoretical calculations had suggested. Assuming that the observation is valid (which is still a matter of debate, as the result has yet to be replicated by another team), it suggests that something in our understanding of early cosmic history is off.

Most recently, Lu Yin, an astrophysicist at the Asia Pacific Center for Theoretical Physics in South Korea, has suggested a new possibility to explain the strange result.

Dynamics in the dark

Yin's work, published to the preprint database arXiv, explored a model called interacting Chevallier-Polarski-Linder dark energy, or ICPL. In this model, dark energy is not a fixed constant of the cosmos but a dynamical entity that can change and evolve in time, resulting in changes in the acceleration rate of expansion. But that ability to evolve immediately opens up a question: What controls the way dark energy can change? In response, this model allows for dark energy to interact with dark matter; their behavior is linked, keeping both of them in check as the universe expands.

There are more cosmological observations than the 21-cm signal. So, to start, Yin tuned the ICPL model to fit other observations, especially ones focusing on the recent expansion history of the universe. With a tuned model in hand, Yin then simulated the evolution of the early universe. Yin found that this ICPL model caused stars and galaxies to appear earlier than in standard cosmological models, which made the ICPL model better at accounting for the strange observed 21-cm signal compared with traditional cosmological models.

This is an intriguing result, but not a slam dunk. The 21-cm observations are still in dispute, and there are other possible explanations for the strange signal. Still, this shows how scientists can approach observations like this and continue to push into the frontiers of understanding dark energy and dark matter.

Space tourists will soon have another option at their disposal, if all goes according to plan.

The new company Space Perspective aims to send paying customers and research payloads to the stratosphere aboard Spaceship Neptune, a balloon-borne pressurized capsule that's scheduled to make its first test flights early next year.

"We’re committed to fundamentally changing the way people have access to space — both to perform much-needed research to benefit life on Earth and to affect how we view and connect with our planet," Space Perspective founder and co-CEO Jane Poynter said in a statement today (June 18), when the company announced its plans. 

"Today, it is more crucial than ever to see Earth as a planet, a spaceship for all humanity and our global biosphere," Poynter said, referencing the "overview effect" commonly cited by astronauts who have flown to space.

Related: The view from space could change the world, Virgin Galactic says

Riding in style

The Spaceship Neptune capsule can accommodate a pilot and eight passengers, who will ride in style. The craft will feature seats, a bar, a bathroom and huge windows that will allow for great views of Earth against the blackness of space, company representatives said.

The craft will launch from the old Shuttle Landing Facility at NASA's Kennedy Space Center (KSC) on Florida's Space Coast. Spaceship Neptune will head east out over the Atlantic Ocean on winter flights and west over the Gulf of Mexico during the summer, a seasonal shift dictated by the prevailing winds. 

Spaceship Neptune will spend about two hours getting up to a maximum altitude of about 100,000 feet (30,000 meters), pulled gently upward by a 650-foot-tall (200 m) balloon filled with buoyant hydrogen.

"Helium has become quite difficult to obtain," Space Perspective founder and co-CEO Taber MacCallum said during a news conference today, explaining the choice of lift gas. "It's used for a lot of medical practices and for launching rockets."

The capsule will spend about two hours high in the stratosphere, above 99% of Earth's atmosphere, then will spend another two hours coming back down again for a total flight time of six hours. Spaceship Neptune will be fished out of the sea by a recovery boat, much like SpaceX Crew Dragon capsules are today. The Spaceship Neptune capsule will be reused, but a new balloon will be needed for each mission.

Space Perspective has not yet set a price for this balloon experience, but a ticket will likely sell for around $125,000 initially, MacCallum and Poynter said. That's about half the most recent stated price for a ride aboard Virgin Galactic's suborbital SpaceShipTwo space plane, which is expected to begin commercial operations soon. (Jeff Bezos' spaceflight company, Blue Origin, is also developing a suborbital space tourism vehicle, called New Shepard, which could get and running soon as well.)

Related: Virgin Galactic's SpaceShipTwo VSS Unity spaceliner in pictures

Spaceship Neptune's gentle ride should make it a viable option for a wide variety of people, including those who are a bit long in the tooth or not in great physical condition. 

"That is really what this is all about," Poynter said during today's news conference. "Everybody should be able to see the Earth from space."

Not every passenger will necessarily need to have deep pockets, either. The nonprofit Space for Humanity has chosen Space Perspective as a "preferred partner" for its Citizen Astronaut Program, which will pay for the flights of selected folks who will serve as space ambassadors after they return to Earth.

"Space for Humanity is cultivating a movement to expand access to space for all of humanity, and this partnership represents a big leap in making that happen," Dylan Taylor, founder of Space for Humanity and CEO of Voyager Space Holdings, said in the same statement.

Space Perspective is also working with NASA. The company signed a Space Act Agreement to use test facilities at KSC and leverage agency expertise in fields such as wind and trajectory analysis, MacCallum said. And Space Perspective has signed a lease agreement with Space Florida, which operates the old Shuttle Landing Facility and associated sites under an agreement with NASA.

The concept for Spaceship Neptune has been decades in the making, dating back to Poynter and MacCallum's two years inside the Biosphere 2 research facility in southern Arizona in the early 1990s. More recently, Poynter and MacCallum helped to develop the concept at one of their previous companies, Arizona-based World View Enterprises. 

World View's balloon-borne capsule was called Voyager, and tickets to ride it were initially pegged at $75,000 apiece. But Voyager's capsule design was quite different, Poynter stressed. And Voyager would have descended under a parafoil and touched down on terra firma, unlike Spaceship Neptune, which is entirely balloon-borne and will make ocean splashdowns.

"There's very little technology overlap," Poynter said during today's news conference.

World View does not seem to be actively developing Voyager at the moment, concentrating instead primarily on its robotic Stratollite balloon system.

Not just Florida?

Spaceship Neptune will initially launch from Jacksonville's Cecil Spaceport in addition to KSC, Poynter and MacCallum said. But the company eventually plans to lift off from a variety of additional locales as well, including international spaceports and sites in Alaska and Hawaii. Ocean platforms may also one day be departure points for the craft, MacCallum said.

Space Perspective still has quite a bit to figure out; the company has not yet decided where it will manufacture Spaceship Neptune capsules or even where its headquarters will be located, Poynter said. But it plans to get up and running quickly, with flight tests beginning in the first quarter of 2021.

And the company is encouraging people to sign up to fly already, even though ticket prices haven't been officially set yet.

"We're already giving people seat allocations, even though you don't have to pay any money now," Poynter said. "That way, the early birds get at the front of the line." 

• Photos: The first space tourists
• 'Overview effect' could help troubled country, astrophysicist Neil deGrasse Tyson says
• NASA's best Earth-from-Space photos by astronauts in (gallery)

Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook. 

The SpaceX Falcon 9 rocket that just launched an Israeli moon lander will make some more history soon, if all goes according to plan.

The Thursday night (Feb. 21) liftoff of the Beresheet lunar lander — which in April will try to become the first privately funded craft to touch down on the moon — and two other satellites was the third spaceflight for this particular Falcon 9's first stage. The booster came back to Earth for yet another landing Thursday and will be prepped for a fourth mission, SpaceX CEO Elon Musk said.

"Highest re-entry heating to date. Burning metal sparks from base heat shield visible in landing video. Fourth relight scheduled for April," Musk tweeted Thursday night. 

Related: Launch Photos: SpaceX Lofts Israeli Moon Lander, Satellites

In subsequent tweets, Musk clarified that "fourth relight" meant the fourth launch for this particular booster. That will be a first; no Falcon 9 first stage has yet flown more than three times. (The upper stage of the two-stage Falcon 9 is not reusable.)

The April mission in question is the high-altitude abort test for SpaceX's Crew Dragon capsule, which the company is developing to fly NASA astronauts to and from the International Space Station (ISS). Crew Dragon is scheduled to fly for the first time on March 2, when it will launch on an uncrewed test mission to the ISS called Demo-1.

The uncrewed abort test will take this same capsule up into the sky, then press its SuperDraco escape engines into service. The goal is to show that Crew Dragon can get astronauts out of harm's way in the event of a launch emergency.

Related: How to Watch SpaceX's Crew Dragon Demo-1 Test Flight Live 

NASA officials have said the abort test is planned for June, but it shouldn't be surprising that Musk thinks it can happen two months sooner than that. The billionaire entrepreneur is known for his ambitious timelines, after all.

Whenever the abort test occurs, it will probably be the last mission for the record-setting Falcon 9 first stage.

"High probability of this particular rocket getting destroyed by Dragon supersonic abort test. Otherwise, at least 20 or 30 missions for Falcon 9. Starship will take over before the F9 fleet reaches end of life," Musk tweeted. 

Starship is the reusable spaceship SpaceX is developing to take people to and from Mars and other distant destinations and — with the help of a gigantic, reusable rocket called Super Heavy — perform every other task the company needs done. 

The Starship-Super Heavy duo could launch people toward Mars for the first time in the mid-2020s if development goes well, Musk has said.

If Demo-1 and the abort test go well, SpaceX could launch astronauts to the ISS for the first time as early as July, NASA officials have said. That mission will still be a test flight, known as Demo-2. Operational, contracted ISS missions would begin after the successful completion of Demo-2.

Aerospace giant Boeing is developing its own astronaut taxi under a similar deal with NASA. Boeing's craft, a capsule called the CST-100 Starliner, is scheduled to fly its first space mission, an uncrewed test flight to the ISS similar to Demo-1, no earlier than April.

Mike Wall's book about the search for alien life, "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate) is out now. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.