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Learn about what might be one of the most important exoplanets we've discovered yet, and what you need to apply to become an astronaut!
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If there's one thing we've learned about our galaxy in the last 20 years or so, it's that our solar system isn't that unusual.

There are a lot of other stars out there with a lot of other planets, even some that are a lot like Earth. Now when astronomers refer to Earth-like worlds, they aren't always saying they have breathable air or liquid water or free Wi-Fi everywhere.

What they mean is that it's a terrestrial planet, rocky and close to Earth size rather than a giant gas ball.

And this week in the journal Nature, astronomers announced that they found another of these terrestrial planets, one that sets a new record. So far, it's the closest terrestrial planet we've discovered orbiting a red dwarf star.

Red dwarfs, also sometimes called M-dwarfs, are some of the smallest stars in the galaxy with about 8-50% of the sun's mass. They're also the most common. About 7 out of 10 stars in our galaxy are red dwarfs, so researchers are interested in what kinds of planets orbit these stars because they can tell us about a whole lot of the galaxy at once.

This particular planet, GJ 1132b, is especially interesting to astronomers because not only is it similar to Earth, it's also close enough that we can check it out directly with telescopes at only 39 light-years away.

The team discovered it while using a telescope array in Chile to monitor red dwarf stars for any dimming, which could mean a planet was passing in front of the star.

Then, one night 1132b star, dimmed a little. After watching the star for a while, the team was able to come up with a spectrum - basically a map of how the star's light changed over time.

By combining that spectrum with a set of equations, they figured out that the dimming came from a planet that's a tiny bit bigger, a little more massive, and almost exactly the same density as Earth, meaning that's it's probably mostly rock and iron.

That makes it the closest, rocky, Earth-size planet orbiting a red dwarf. At least that we found so far.

But with only a 1.6 day orbit, it gets around 19 times the radiation from its star than we do from ours. So, not exactly habitable by our standards. And the Wi-Fi signal is probably weak there at best.

But it could have an atmosphere. And because it's so close and passes in front of its star so often, we can study it, and hopefully find out what its atmosphere is made of.

Meanwhile, astronomers are going to keep watching red dwarfs for signs of other planets because there are probably more Earth-like worlds close by.

If you want to go out and explore space for yourself though, now is a really good time because NASA is looking for astronauts.

For the first time since 2011 when they picked 8 people from more than 6,000 applications, the space agency is recruiting its next class. But the applications are a little different this time around.

Instead of traveling in the Russian Soyuz space capsules, these astronauts will launch from U.S. soil meaning not only would you be eligible for trips to the International Space Station, you'd be able to fly on the two rockets being developed by private companies right now - SpaceX's Crew Dragon and Boeing's CST-100 Starliner.

You'd also be trained to fly on Orion, the NASA craft that's being designed for deep space missions like one to Mars. But that doesn't necessarily mean you'd go to Mars especially right now since the first manned NASA mission to Mars is scheduled for some time in the 2030s.

So what do you need to apply to one of the most selective programs in the world? Well first you'll need to be a U.S. citizen. You'll need a bachelor's degree in a STEM field though certain degrees like nursing and psychology don't count.

And you'll need 3 years of relevant experience. Some advanced degrees count as experience, but a thousand hours flight time piloting a jet engine aircraft would be a big help.

If that sounds like you, just make sure you can pass the physical and psychological exams. That means no pre-existing conditions because the last thing NASA wants to do is scrub a mission because one of its astronauts needs emergency surgery.

They'll also test your cardiovascular health, so it might be a good time to fire up the old treadmill. But one of the coolest things is that there's no age requirement. And how well you have to do to pass depends on how old you are. You don't need perfect eyesight either, it just needs to be correctable to 20/20. Even if that's with glasses or contacts.

The psychological tests are mainly to make sure you can handle months of being cooped up with the same people and that you're the type of person who will keep their head in an emergency.

Still think you've got the right stuff? Well, applications open December 14th and close in mid-February, so you better get to work.

And let us know if you're accepted. You should find out sometime in 2017. So good luck, and thanks for watching this episode of SciShow Space News.

And don't forget to go to and subscribe.