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  • You may have heard that it's not smart to look directly at the Sun,

  • and that's for good reasonit's pretty bad for you.

  • But it turns out that stars can be problematic in a similar way when we're looking out into space:

  • their glare can stop us from seeing the stuff we want to see.

  • But NASA's shiny new tool just might let us see more worlds, in more detail, than ever before.

  • These overly-bright stars are pesky because we're looking for exoplanets,

  • or planets outside of our own solar system.

  • And NASA's Wide-Field Infrared Survey Telescope is expected to help us add thousands more exoplanets

  • to our database.

  • But first we're going to have to solve the problem of the stars that these exoplanets orbit.

  • The way the telescope 'sees' these planets is essentially by recording the photons that bounce off of them.

  • These relatively faint signals have to compete with the extreme brightness of the star itself.

  • So WFIRST is essentially going to have to cancel out billions of photons from the star

  • for every single photon that they want to capture of the planet that we actually want to see.

  • We're gonna need a pretty big pair of sunglasses for that taskor maybe more accurately, starglasses.

  • That incredibly sophisticated pair of starglasses is actually called a coronagraph.

  • It's an additional instrument that will travel with the telescope,

  • and it allows us to see beyond the bright glare of stars in a really clever way.

  • Some simpler coronagraphs just use a dark, opaque piece of glass to block out the bright light

  • coming directly from the starkinda like your sunglasses do.

  • But WFIRST's more sophisticated coronagraph consists of a few complex light-blocking steps,

  • including a pair ofdeformable mirrors,” or mirrors that are flexible and can change shape.

  • In reaction to tiny errors that may crop up as the telescope operates,

  • these mirrors can be deformed by hundreds of tiny actuators that manipulate them into different shapes

  • and configurations, filtering out the light from star.

  • And this manipulation of the mirrors is so precise they can fix errors smaller than the width of a strand of DNA.

  • This precision lets us see the finer details of the planets we're looking at.

  • WFIRST will be the third NASA mission to carry coronagraph technology,

  • and will probably be two to three orders of magnitude more powerful than any coronagraph

  • that's ever flown in space before.

  • It could let us see some crazy stuff,

  • like star systems as they're just beginning to form,

  • which could help us understand how ours might have come to be.

  • And it'll help us see way more exoplanets in general

  • about 2,500 of them, some of which will be rocky planets in the habitable zone,

  • where liquid water could exist, which you know, could host life, no big deal!

  • That's one hell of a pair of starglasses.

  • WFIRST will launch in the mid-2020s,

  • and its coronagraph has already passed an important milestone.

  • It's been through a design review,

  • which means that it's met all of its design requirements on budget and on schedule, which is a huge feat.

  • That means that now, NASA scientists and engineers get to actually start building it!

  • I think one of my favorite parts of this project is that after WFIRST launches and has proven itself

  • over its first 18 months, use of the telescope and its data will be totally open to the scientific community.

  • That means that scientists around the world will be able to submit proposals for work on the telescope.

  • Which is important because WFIRST isn't just looking at exoplanets

  • it will also observe and take measurements that may help us learn more about dark energy

  • and infrared astrophysics.

  • WFIRST and its sophisticated spectacles will be in space for at least five years,

  • and will blaze a trail for a clearer view of space.

  • These innovations will also guide and influence coronagraph technologies

  • for even more advanced missions in the future,

  • allowing open science to peer further into space and see in more detail than ever before.

  • For more on exciting space tech developments, check out this video here,

  • and make sure you subscribe to Seeker to keep up with all of your telescopic news.

  • Let us know what other space-peering advancements you want us to cover down in the comments down below,

  • and as alwaysthanks so much for watching.

You may have heard that it's not smart to look directly at the Sun,

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美國宇航局的WFIRST太空望遠鏡將提供一個前所未有的宇宙觀 (NASA’s WFIRST Space Telescope Will Offer an Unprecedented Look at the Universe)

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    林宜悉 發佈於 2021 年 01 月 14 日
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