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  • This episode is sponsored by Squarespace.

  • From websites and online stores to marketing tools and analytics,

  • Squarespace is the all-in-one platform to build a beautiful online presence and run your business.

  • [♪ INTRO]

  • Finding a new exoplanet used to be a really big deal all on its own.

  • I remember these days!

  • I was alive when we found the first exoplanet!

  • But now that we've found thousands of planets orbiting other stars,

  • and astronomers don't just want to know that a planet exists, they want to know what it's like.

  • New work published last week in the journal Science shows one creative way to answer that question.

  • And the work reveals that, throughout the galaxy, planets seem to be made up of rock

  • that's a lot like the rock you might pick up in your backyard.

  • Understanding the composition of exoplanets is tricky business,

  • because we can't just like, fly over and bring a piece back to the lab

  • and do a bunch of chemistry on it.

  • In some cases, you can learn a lot by watching how light from a planet's star gets altered

  • as it passes through the planet's atmosphere.

  • But that won't get you anywhere with a planet that doesn't have an atmosphere.

  • And sometimes scientists care more about what's under the surface than what's floating above it.

  • For decades, there's been basically no solution for these problems,

  • but this new research came up with an unusual solution to the problem:

  • scope out worlds that are in the process of being destroyed.

  • The work focuses on six white dwarf stars,

  • the burned-out cores left behind when stars like our Sun reach the end of their lives.

  • White dwarfs are extremely dense, and their powerful gravity can shred any asteroids or

  • planetary fragments that wander too close.

  • As that material falls onto the star, it pollutes the star's outer layers with new elements.

  • Astronomers can see the signatures of those elements in the star's light.

  • In this study, researchers scoured past observations of nearby white dwarfs

  • in search of the six most common elements in Earth's crust:

  • iron, oxygen, silicon, magnesium, calcium, and aluminum.

  • And they found them.

  • But their most important finding was that there wasn't just iron and oxygen in these rocks,

  • there was iron oxide, better known as rust.

  • Iron oxide is common in rocks from our solar system, but it only forms under the right conditions,

  • such as in places with tectonic activity.

  • Finding it in these far-flung locations means that it's probably common

  • for rocky planets to have tectonic plates, just like Earth.

  • And the fact that this iron oxide exists also suggests

  • that these planets could have magnetic fields and atmospheres just like us.

  • Basically, the study implies that these far-off worlds are pretty similar to Earth and its rocky neighbors,

  • which could make it a whole lot easier to understand the nature of exoplanets.

  • Also, watching a planet get destroyed is a pretty fun way to do science.

  • I hope there wasn't anybody, like, living their best life there.

  • They certainly aren't anymore.

  • Last week, we also got some good news about NASA's ability to explore closer to home.

  • As part of its Artemis project to return astronauts to the Moon, the agency revealed a new spacesuit

  • designed to better meet astronauts' needs wherever they're working.

  • The most important change is in sizing.

  • NASA's current suit can trace its origins to the ones worn by Apollo astronauts on the Moon.

  • Astronauts who, of course, were all men.

  • As you might expect, this has created problems,

  • like in early 2019, when NASA was forced to cancel the first planned all-woman spacewalk

  • because they couldn't come up with two working suits that fit them.

  • That historic walk finally happened last week,

  • but the whole affair highlighted the ongoing inequity faced by female astronauts.

  • NASA's new design solves that problem, at least, when it comes to spacesuits.

  • With this new program, each astronaut will have their entire body 3D-scanned.

  • And with that data in hand, engineers can match the astronaut with the most comfortable suit.

  • The spacesuits are designed to fit nearly all body types, women, and men.

  • They're also easier to put on and more flexible,

  • which should make it easier for future Moonwalkers to carry out their tasks on the surface.

  • There's still lots of work left to do, though, and NASA expects it will be about two years

  • before an astronaut on the International Space Station takes one for the first test-drive.

  • But when it's ready, this new suit could support astronauts for decades of future exploration.

  • So good thing it also looks pretty cool.

  • Finally, we wanted to share some happy news about NASA's Mars InSight mission,

  • which has been working to understand the interior of Mars since last year.

  • One of Insight's key instruments is the Heat Flow and Physical Properties Package

  • or HP^3, which was provided by the German Aerospace Center.

  • HP^3 is designed to burrow several meters underground and make temperature measurements

  • that will help scientists calculate how quickly Mars is losing heat.

  • Its centerpiece is what's called themole,” which is sometimes described as a “self-hammering nail.”

  • It just kind of slams itself deeper and deeper into the ground,

  • dragging a wire behind it to relay data back to InSight.

  • But back in March, the mole suddenly stopped making progress

  • after traveling only about 35 centimeters below the surface.

  • Now, seven months later, engineers finally got it moving again!

  • The problem turned out to be a lack of friction.

  • The mole relies on friction with the surrounding material to drag itself further down,

  • but the upper layer of the Martian surface is crustier than scientists expected,

  • so the mole had trouble grabbing hold.

  • NASA's solution was pretty clever, they used InSight's robotic arm

  • to press the mole against the side of the borehole, giving it the friction it needed to move forward.

  • So far, it's only gone a couple of extra centimeters,

  • but that is a lot more than the nothing they were getting before.

  • So score one for engineering a solution from a hundred million kilometers away.

  • From stealing a peek at dying worlds to 3D-scanning astronauts and lending a hand to a self-hammering nail,

  • this was totally a week for out-of-the-box thinking.

  • Making it up as you go is part of what makes exploration so cool.

  • Engineering creative solutions in space is one thing.

  • But that kind of creativity can also go a long way here on Earth.

  • And say you had a great idea, like if you wanted to start a campaign to plant trees

  • and let the world know about it.

  • You might want to create a website.

  • Squarespace is one place to start.

  • It's got powerful blogging tools, so you can easily share stories, photos, videos, and updates.

  • You can even schedule your posts to make your content go out when you're ready.

  • The blogging platform also supports a sharing button

  • that your visitors can use to share content on Facebook, Twitter, Reddit, and more.

  • You can also reach people in their inboxes by setting up a Squarespace email campaigns.

  • It's easy to use the Squarespace platform to unify your brand voice,

  • from your homepage to your emails.

  • And you can get a free trial.

  • When you're ready to get started, head over to squarespace.com/SPACE

  • and use the codespaceto save 10% off your first purchase of a website or domain.

  • [♪ OUTRO]

This episode is sponsored by Squarespace.

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破壊された太陽系外惑星の意外な秘密|サイゾーウーマンニュース (The Surprising Secrets of Destroyed Exoplanets | SciShow News)

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    林宜悉 に公開 2021 年 01 月 14 日
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