SciShow Space is supported by Brilliant.org - a problem-solving website that teaches you how to think like a scientist. [♪ INTRO] You can probably agree that humans… we love to classify things.

Whether we’re sorting animals into species or arguing over whether Pluto is a planet, it’s almost impossible for us to resist sorting the stuff around us. Unfortunately, nature doesn’t care what we like to do, and we keep making discoveries that defy our precious categories, like an object in the asteroid belt called… this.

Or 288P for short. In a paper published last week in the journal Nature, a team of astronomers reported that 288P is a binary asteroid… that kinda acts like a comet. Astronomers discovered the object in 2006, hanging out in the main asteroid belt between Mars and Jupiter.

At the time, it looked like all the other asteroids, basically, a small, rocky space potato, so that’s what we called it. But then, in 2011, when the object neared the Sun, scientists saw it producing a temporary tail and halo, or coma, of dust and water, which meant this so-called asteroid was also acting like a comet. By itself, this isn’t that weird.

There are actually enough main belt asteroids that sometimes act like comets that, surprise! We have a category for them: main belt comets. But now, we’ve discovered that this object is even stranger.

In the latest paper, images from the Hubble Space Telescope revealed that it isn’t one kilometer-sized space rock, but two, orbiting one another about 100 kilometers apart. Binary asteroids are pretty common, but 288P is the first binary and main belt comet. It also combines features we’ve seen in other binaries that make it unique: The two rocks are similar in size, the separation between them is pretty far, and the shape of their orbit around each other is highly elliptical.

Now, 288P should have run out of water ice a long time ago, so it shouldn’t be able to create that comet-like tail anymore. But since it can, that suggests it became a binary very recently, at least in astronomical terms, about 5000 years ago. Previous work estimates that 288P existed as a single space rock for millions of years, but it became a binary thanks to rotational fission, or from breaking apart from spinning too fast.

Then, the newly-exposed water ice vaporized and pushed the two rock fragments in opposing directions. 288P is the first of its kind, so it’s difficult to tell how many objects like it are in our solar system. And since the pieces were relatively small and far apart, others will be hard to spot if they exist. But understanding objects like it could help astronomers explain how the solar system evolved.

And since research suggests icy asteroids played an important part in bringing water to Earth, it may help us figure out how so much water got here, too. Meanwhile, the European Space Agency is studying what happens when water leaves Earth. By which I mean sacks of water, which, I’m talking about humans, just people.

People are bags of water. Right now in a clinic in France, 10 volunteers are staying in bed for 60 days to see if a cocktail of antioxidants and vitamins can fight the negative side effects of living in space. Living in orbit has its perks, but since astronauts’ bodies aren’t constantly fighting gravity, the weightlessness they experience causes a lot of physical side effects.

Among other things, their bones grow brittle, their muscles decay, their bodily fluids get redistributed, resulting in what’s called, no joke, “puffy-head, bird-legs” syndrome. Learning how to fight those effects is especially important for long-term space missions, like for when we send people to Mars, because once we get there, we’ll need the strength to walk around, and do science stuff. Instead of spending oodles of money launching more people into space, or only studying the few astronauts that go there, researchers mimic microgravity here on Earth using special bed rest studies.

The subjects’ beds are tilted down 6 degrees so that their heads are lower than their feet, which simulates how fluids get redistributed in space. And once they lie down, they have to keep at least one shoulder touching the bed at all times. This study will conduct 15 experiments to measure things like vital signs or the participants’ mood.

Half of the subjects will take a mixture of antioxidants and vitamins to supplement their nutrition plan, and the other will serve as the control group and won’t take any supplements. After the 60 days are up, they’ll all undergo the same rehabilitation program that ESA astronauts do after returning to Earth to restore some of that lost bone and muscle strength. Now, lying in bed for two months eating and watching Netflix might sound like an easy way to spend your time, but no.

You’ve got to put your whole life on hold, eat a strictly-controlled diet, and be okay with your body getting weaker. You’d also have no privacy, be subjected to constant medical tests, and would have to do everything without sitting up, everything. What I’m saying is, you’d have to poop lying down for two months.

This won’t be the last bed rest study the ESA does, next August, they’ll see if making artificial gravity could counteract space’s side effects, but it will teach us a lot about how our bodies work in space. One way or another, volunteering for a bed rest study is no joke, but if we’re ever living in space, we’ll have those bed-poopers to thank. So maybe it’s worth it.

But even if bed rest studies aren't for you, there are still plenty of ways you can get involved in space exploration and astronomy. Brilliant.org is a problem-solving website that teaches you how to think like a scientist. Brilliant presents short, conceptual quizzes that supplement other instructional styles.

A great way to retain what you’ve seen on SciShow Space is by actively solving problems on Brilliant. Each course guides you through easy and challenging problems with interactive graphics and questions. This course called Gravitational Physics has a great refresher on the Keplerian orbits I worked through a couple questions to learn the simple criteria to tell when a comet will become trapped in an orbit around the sun If you like getting smart, you’ll like these problems on Brilliant.

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