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  • Weve found an Earth-like planet orbiting a star RIGHT NEXT DOOR TO OUR SUN!

  • Pack your bags, kids!

  • LET'S GO TO PROXIMA B!

  • Hello there soon-to-be Proxima Centurians!

  • Trace here for DNews.

  • A few weeks back we started hearing rumors, really exciting rumors tales of the discovery

  • of a planetand then we freaked out.

  • Because those rumors are true!

  • Today, astronomers announced our closest neighbor star, Proxima Centauri, has a rocky planet

  • orbiting in the habitable zone.

  • Ladies and gentlemen, this is Proxima b!

  • The planet is around 30% more massive than Earth and is mind-blowingly close to its star.

  • It only takes a little over 11 days for the planet to complete a single orbit -- it's

  • 95 percent closer to Proxima than we are to our sun. It doesn't burn up because Proxima

  • is a red dwarf star, so it's much cooler and smaller than our sun.

  • The habitable zone around any star is the distance at which a planet needs to orbit

  • that’s not too hot and not too cold for liquid water to exist on its surface. As

  • far as we can tell, where there's water there's a possibility for life.

  • This is why astrobiologists get excited when they find exoplanets in habitable zones.

  • Just because a planet is in a habitable zone, though, doesn't mean we can live there.

  • And even though liquid water could exist on Proxima b, that doesn't mean it has any.

  • On top of that, red dwarf stars like Proxima Centauri emit more intense x-ray flares, and

  • ultraviolet energies than our own sun.

  • So, while we probably can't live there, it's exciting because before 1995 we'd never confirmed

  • a single exoplanet.

  • For all we knew, there were no planets out there

  • Much less one RIGHT NEXT DOORonly four point two light-years away!

  • Which is still far, but in astronomical terms that's ludicrously close.

  • So this is exciting for many reasons.

  • First, this Proxima b is the closest exoplanet beyond our solar system. Which is great.

  • But, the fact that it’s Earth-sized AND orbits inside the habitable zone are both

  • amazing!

  • Because c'mon.

  • INTERSTELLAR MISSION, AM I RIGHT?

  • There’s currently a lot of excitement for that possibility and plans in place to send

  • spacecraft to other stars, but we need new technology.

  • Our fastest current spacecraft would take about 80,000 years to get to Proxima Centauri,

  • but if we could go 10-percent the speed of light we'd cut that to 50 years.

  • We can't go that fast yet, but now maybe engineers and scientists will be inspired to figure

  • out how to get to this new planet.

  • Especially, if it’s Earth-like when we get there!

  • But that’s a big IF.

  • Though the media is calling Proxima b anEarth-likeworld, that’s not particularly accurate.

  • Just because a world is small and rocky like Earth, and orbits in the habitable zone, doesn’t

  • make it an oasis fit for life.

  • Just look at Mars and Venus; both of those are in our habitable zone and neither are

  • particularly Earth-like!

  • I already mentioned the powerful X-ray and ultraviolet radiation that Proxima b is likely

  • subject tonot great for biology.

  • But also, red dwarfs are known to flare regularly, blasting any planets with radiation.

  • This means the Proxima b would have to have a thick atmosphere and powerful magnetosphere

  • to protect it from damaging space weather if life were to flourish.

  • For now, we have no clue if it has either.

  • And then there’s the question of Proxima b’s really tight orbit.

  • When a planet orbits its star so closely, it will becometidally locked” -- this

  • causes one hemisphere to constantly face the star while the other is in constant night.

  • That is VERY un-Earth-like, and can make for INSANE planetary weather.

  • One side cooks while the other freezes.

  • Look, in the end, this is still a VERY important AND historic discovery.

  • To have any world that just so happens to have any Earthy qualities on our galactic

  • doorstep is an incredible stroke of luck and will undoubtedly become a point of scientific

  • interest that could inspire Earthlings to see interstellar travel as a possibility.

  • When it comes to finding these tiny little planets, how do we know so much about them when

  • thay are so far away?

  • DiscoveryNews Space Producer Dr. Ian O'Neill explains that for you, here.

  • Special thanks to Dr. Ian O'Neill for all his help with this story!

  • We couldn't done it without you. You're a star, man!

  • How do you feel about this discovery?

  • Are you excited? Are you nervous? You want to go to there?

  • Let us know in the comments, and please subscribe. so you'll get more DNews

Weve found an Earth-like planet orbiting a star RIGHT NEXT DOOR TO OUR SUN!

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地球に似た惑星を発見!知っておきたいこと (Earth-Like Planet Discovered! What You Need To Know)

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    Sh, Gang (Aaron) に公開 2021 年 01 月 14 日
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