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  • You up for a little space adventure?

  • Well, ok then, strap in!

  • But today's destination won't just be a little cosmic pit stopit could be your

  • next home!

  • Basically, astronomers have recently found a potentially habitable planet, but the key

  • word here ispotentiallyso don't go packing your bags just yet!

  • This planet is called Barnard's Star B.

  • (If you're wondering who Barnard is, I'll get to that a bit later.)

  • Anyway, if you step on its surface, you'd probably see nothing around you except endless

  • ice fields.

  • Look up high into the dark sky, and you'll see a little murky-looking circle.

  • No, that's not Barnard's moonit's the planet's sun.

  • Now look down.

  • Deep under your feet lie countless rivers, lakes, and seas of liquid methane.

  • Ok, time out.

  • None of this sounds like something I'd callhabitable,” at least not for humans!

  • So, that's it, there can be no life here.

  • Case closed!

  • Thanks for watching, remember to give this video a “like,” share it with your...

  • Oh, I'm kidding!

  • Give Barnard a chance, will ya?

  • Hey, ya never know, he could be hiding a lot more life than you'd think in those rivers

  • and seas of methane!

  • Ok, back to our story.

  • Let's explore that murky little circle that I told you was Barnard's sun, the one the

  • planet is orbiting around.

  • This star is only located 6 light-years away from us, and it's the 4th closest star to

  • our solar system.

  • Try to imagine our sun 5 times smaller and much less bright.

  • Well, that's Barnard's Star for you, and it has some other absolutely unique properties.

  • Believe it or not, it's the only star that bears the name of the astronomer who studied

  • it.

  • Now, let's meet him!

  • Though Edward Emerson Barnard wasn't the first to discover this star, he proved in

  • 1916 that it's the fastest star known to us.

  • Yes, all stars are moving across the universe, but Barnard's Star is doing it at top speeds.

  • And not only that, it's actually constantly approaching our solar system.

  • Hey, don't worryit won't cause any trouble to anyone!

  • But one day in the next 10,000 years, it'll come closer to us than the Sun's current

  • nearest neighbor-star: Proxima Centauri.

  • Well, 10,000 years may sound like a lot, but in the cosmic scale of our galaxy, it's

  • a mere moment, maybe two at the most.

  • Barnard's Star is what astronomers call a red dwarf – a small, dim, and truly ancient

  • star that's getting pretty close to the end of its life cycle.

  • And, yes, Barnard's star fits the bill of a red dwarf.

  • It's so ancient that it probably saw the birth of the Milky Way Galaxy itself.

  • At around 10 billion years old, it's easily twice as old as our own Sun.

  • For something normally as bright and heavy as a star, being small, dim, and super-fast

  • is pretty remarkable!

  • So it's no wonder Barnard's Star drew so much attention from astronomers.

  • Ok, but what about all this talk of a habitable planet?

  • I'm getting there!

  • So, the first person to assume there was a planet somewhere near this star was astronomer

  • Peter van de Kamp.

  • Back in the 60s, he observedwobblesin the star's movement.

  • So, wobbles = planet?

  • Well, yeah, pretty much!

  • You can even conduct your own little experiment and see for yourself.

  • Try and lift something heavy in both hands, and spin it around yourself a few times as

  • carefully as you can.

  • You'll quickly notice that this object isn't the only thing that's movingit'll

  • move you too!

  • Or at least it'll make you wobble a bit.

  • The exact same kind of wobble is present when a star is spinning a planet around itself.

  • Unfortunately for Peter van de Kamp, his observations were later proven to be flawed, but that doesn't

  • mean he was completely wrong because there is, indeed, a planet around Barnard's Star!

  • And we've now come full circle.

  • Barnard's Star B was finally discovered on November 14, 2018.

  • An international team of astronomers led by Dr. Ignasi Ribas from the Institute of Space

  • Studies of Catalonia started their research 20 years ago when they observed Barnard's

  • Star doing some other weird stuff besides wobbling.

  • From time to time as it was moving across space, its light would change.

  • It'd look kinda red one minute and then become bluish the next.

  • Besides the whole wobbling thing, this kind of shift in starlight is another sign of an

  • orbiting planet.

  • They took lots of measurements with the most advanced astronomical equipment you could

  • imagine, and they came out with 99% certainty that the planet Barnard's Star B exists.

  • Now, it's considered to be a super-earth class planet.

  • Sounds kinda epic, right?

  • Something like Earth's cooler older brother, and that's not exactly wrong!

  • Barnard's Star B has slightly more than 24 hours in a day, and it's always sunny

  • there no matter what.

  • And now it's definitely starting to sound like a better version of Earth!

  • Butsuper-earthis just the term astronomers use to describe only the size of a planet

  • that's larger than Earth but considerably smaller than ice giants like Neptune.

  • As for Barnard's Star B, it's about 3 times more massive than our planet.

  • But it's nothing like it, and you already know that by now!

  • Remember those seas of liquid methane?

  • Yeah, it's all coming back to me!

  • Anyway, besides that, this planet is a huge ball of rock and ice that lies beyond the

  • habitable zone of its star.

  • Even though it's closer to Barnard's Star than our Earth is to the Sun, its star provides

  • only 3% of the light that our Sun does.

  • (Remember, it's a small, dim, red dwarf.)

  • And even if we still decided to meet “a new dawn for humanityon this planet, there'd

  • be one major problem: there wouldn't be a dawn at all!

  • Barnard's Star is so dim that it barely lights up anything on the planet.

  • And how would you feel about living in temperatures of -275°F below zero?!

  • Well, that's the estimated average temperature on the surface of Barnard's Star B, so,

  • grab your mittens!

  • The only planet-like object in our solar system that resembles Barnard's Star B would be

  • Saturn's largest moon: Titan.

  • And that's exactly what makes the discovery of Barnard's Star B so exciting!

  • Astronomers are really interested in studying Titan, and that's why they've become so

  • enthralled by this new discovery.

  • This planet, just like Titan, is partially composed of ice, which means that it has water.

  • Of course, it's too cold for liquid water to be there, but it has its own forms of lakes,

  • rivers, and oceans that you already know are liquid pools of methane.

  • And according to a 2015 study at Cornell University, chances are that simple methane-based lifeforms

  • can develop and survive in these conditions.

  • So, in a nutshell, there could be something alive floating in a methane lake under the

  • surface of an icy planet 6 light-years away from where you're sitting right now.

  • Pretty cool, huh?

  • But let's not forget that the existence of such lifeforms is pure theory.

  • So the idea that this newly found Barnard's Star B planet is habitable for us humans is

  • really far-fetched for now.

  • But in the miraculous world of science, there's always room for new unexpected discoveries!

  • Not to mention, even if Barnard's Star B isn't exactly a “swipe rightfor us

  • Earthlings, we've still got some other potential candidates.

  • Actually, one of them is right in our neighborhood!

  • Remember Proxima Centauri?

  • Ya know, our Sun's closest neighbor-star?

  • Well, it's got a planet of its own called Proxima Centauri B. (Lengthy name, but we

  • can work on rebranding if we decide to move there!)

  • This planet is actually pretty fascinating!

  • It's slightly bigger than Earth, and it receives just enough light from Proxima Centauri

  • to keep temperatures above 32°F. Although one side of the planet never sees starlight

  • and the other is literally baked by its sun, the planet's equator could be quite livable,

  • even for humans!

  • So, would that make us Proxima Centaurians?

  • Proxima Centauri Bees?

  • Eh, like I said, we'll work out the details later!

  • So, do you really think humankind will ever find a habitable planet to make our new home,

  • or is this just the stuff of sci-fi movies?

  • Let me know your thoughts down in the comments!

  • And don't forget to give this video a “like,” share it with your friends, and clicksubscribe

  • to always stay on the Bright Side of life!

You up for a little space adventure?

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    Amy.Lin 發佈於 2021 年 01 月 14 日
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