The James Webb Space Telescope Is Assembled! Finally! | SciShow News

[INTRO ♪] For years, NASA has been working on an amazing telescope. It’s called the James Webb Space Telescope, or JWST, and at one point, it was intended to launch in 2007. We’ve been talking about this project since SciShow started, because James Webb could transform our understanding of the universe. But honestly, being a fan of this telescope is sometimes hard work. After years of seeing it fail tests and get
postponed, things can feel discouraging. Today, though, I have some good news! Last week, after more than a decade of delays, the two halves of the telescope have finally been joined together. Although it won’t do identical work, James Webb is the successor to the Hubble Space Telescope, which will likely stop working in the mid-2020s. And once Webb launches, it will be charged with a full complement
of missions. Using infrared light, it will study the composition of exoplanets, probe the oldest galaxies we can see, and maybe even answer our questions about what the universe is made of. But before it can do any of that, it needs to launch. And before it can launch, it needs to be fully tested. Until recently, Webb’s two main halves were tested separately. But now, we can test them together. One half consists of the telescope itself. That’s the part with gold-coated mirrors and a suite of instruments. The other half has the spacecraft, which will steer the telescope, along with the giant, five-layer sunshield that will block light from the Sun, Earth,
and Moon. Blocking this light will help keep the telescope
cold — which is a must, since heat is a major source of infrared radiation. So, if it’s not cold enough, an infrared telescope’s own heat can overwhelm its instruments while it’s trying to monitor distant, dim
objects. The sunshield will solve a lot of that problem, but the telescope will also have a bit of
cold helium to keep some of its instruments extra chilly. Of course, just because the telescope is mostly-assembled doesn’t mean it’s ready for launch. Engineers still have to connect the electronics between the two halves, and after that, they have to test them all
together. They’ll have to make sure they wired everything correctly and that the equipment will survive deployment and the vacuum of
space. That means there’s still room for error. But hopefully, things will go well, and the telescope will finally launch in March
2021. Thankfully, even if Webb doesn’t launch
for a while, there’s plenty of other work to do in astronomy. For example, researchers are still hunting for the first solid evidence of an exomoon — a moon orbiting a planet outside the solar system. Moons are usually much smaller than their planets, so even when we find an exomoon candidate, it’s tricky to isolate the signal and confirm that it’s actually there. One team of astronomers thinks there’s a way around this, though. Their paper has been accepted for publication in The Astrophysical Journal. And in it, they propose you can find certain exomoons by studying their planet’s
chemistry. And using this method, they’ve even found an especially exciting
candidate! This paper focuses on a type of planet called hot Jupiters. These are gas giants that orbit so close to their stars that their year could be as little as a few days on Earth. Until recently, there wasn’t much evidence that a moon could exist in a stable orbit around a planet like this. So the first thing these scientists did was use math to confirm moons could live there. And next, they proposed a way we could identify them. Drawing on earlier research, they suggested you could find some exomoons by looking for certain gases in their planets’ atmospheres. This idea is actually based on what researchers see with Jupiter and its third-largest moon, Io. Io has hundreds of active volcanoes that spew out lava, sulfur-based gases, and other elements — like sodium and potassium. And some of those compounds get incorporated into Jupiter’s upper atmosphere. That’s important. Because at least in our solar system, elements like sodium and potassium aren’t normally found in the upper atmospheres of gas giants. They only seem to get there through external sources — like volcanic moons. So, these astronomers hypothesized that if you detect either sodium or potassium around a hot Jupiter, it could have a moon like Io. This basic idea isn’t new, but these researchers were among the first to see if it applied to hot Jupiters. And as it turns out, it might. In their study, they looked at data from 14 of these planets, all of which had sodium or potassium signatures in their upper atmosphere. Then, they ran analyses and identified one that seems most likely to have a moon. It’s called WASP-49b, and is located 550 light-years away. If this finding is validated, it would be the first confirmed exomoon. But even if it’s not, this method is still a really creative way of studying objects that are super far from Earth. It combines the familiar things that are close to us with alien worlds hundreds of light-years from here! At this point, it’s unclear if this technique could be used to find moons like ours around planets like Earth. But hey: Maybe we’ll need even more creative methods to do that. There’s a lot to explore in space — which is part of the reason science fiction
is so fun. You get to think about what would happen if, say, a bunch of alien robots called Carl suddenly appeared on Earth. Okay, let me explain. About a year ago, Hank, who co-hosts this channel with me and started SciShow and does lots of cool things, released a book that he worked on forever called An Absolutely Remarkable Thing. And that book is now available in paperback, which is just so much more cozy to hold! So if space, robots, social media, or just the general state of humanity are
things you’re interested in… you can pick up
the paperback of An Absolutely Remarkable Thing wherever you like to get your books. [OUTRO ♪]

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  1. imagine the kinds of telescopes (and other things) we could have if NASA and SETI and any other space study organizations had even one tenth the budget the military has.

  2. bizarre that she mentioned SODIUM AND POTASSIUM. i have sodium (table salt) and potassium (in bananas) in my kitchen. Sugar and alcohol is sometimes in nebulas. So many of the daily life things that make up our regular world are really from space.

  3. Video idea?: Why are they sending the James Webb telescope to L2 and not a sun synchronous orbit? What are the pros and cons of each?

  4. Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash, Please don’t crash, please don’t crash,.


  5. After the JWDST is operating, would it be cheaper/quicker/make sense to launch like 10 more to increase our work rate and field of view? I feel like NASA put forth all of this intellectual investment to only put out 1.

  6. Between launch and the 10k things that need to happen for it to get into its complicated orbit ill be very surprised if JW even makes it. And no way to get to it wonder how long b4 a part malfunctions. I sound negative but I'm really not. Need to get on with it and the next 5 space telescopes. Great vid

  7. Exomoon huh? What do you think you’ll find there? Poisoning gases and a waste of time? I thought we were looking for life on other worlds lol

  8. For Pete's sake, take a breath give a pause, between sentences! I know you've edited the video in this way to cram as much sound in your 5 mins, but … 😁

  9. Great topic… now a better one… where is the guy with the great voice? Is he no longer working with this channel and if not what channel is he with?

  10. Every single piece of the launch vehicle is going to be checked about a million times over by a lot of very, very paranoid people :/

  11. All this effort and god knows resources should of been used to find what we need not what we already have. It’s like the diamonds we detected that are too deep to get.

  12. Caitlin, thanks for the video. May I suggest that the jumpcuts are too frequent now… can you dial back the enthusiasm and present the update more naturally? Thanks.

  13. Wow….at first I thought this young lady was on adderall and then I realize my playback speed was set to 1.25…That was trippy…this legalized pot thing is just not working out for me.😁😂Great News On James Webb telescope🔭

  14. How come at 2:20 it’s the same picture of earth that is always used… I would think by now NASA would have more/better/newer pics, I’ve been seeing that one since like 1973.

  15. Я закрыл это видео когда увидел ведущую. Никого не хотел обидеть, но это жестоко…

  16. 0:28 ”I have a good news”, hm ?

    A long time ago (at my work), I borrow
    a drill bit from my friend. After half an
    hour he ask me about his drill bit. So,
    I told him, that I have a two news for
    him, a good one and a bad one.
    Which one you wish to hear first, I ask
    him. The bad one first, he says.
    OK I have broke your drill bit.
    And what is the bad news, he ask.
    I almost done my job.

  17. Meaning Trump never mentioned Space Telescopes, Wiki conspiracy lies and Space Forces ( get a life with a real James Webb Space Telescope )

  18. When they wire the 2 half’s together I hope they know that + is positive, and
    – is negative !
    Or they would have to spend 7 billion dollars to send astronauts up there to
    swap the wires over !!

  19. This got me excited. Now hurry up NASA and get it up there and let’s find some habitable planets and unlock whole bunch of secrets that space is keeping from us 🤯

  20. What is this amateur astronomy ! Gas giants are known to flare and in the process spit out chunks of their cores. Hence all the moons around Jupiter and Saturn etc. Some scientists are obviously still living in the stone age.

  21. JWST might blow up during launch, there are some rumors out there that the money was embezzled and an accident at launch can cover it all up.

  22. Assembled? You kidding right, its been assembled for launch since October 8th 2015!!! So much red tape, it won't launch till 2026!!

  23. How dare the gubberment fund these things with taxpayer dollars! If these scientists want to build things like this they should pay for it with their own money or money from willing donors!

  24. Seems it woulda been smart to do several launches and assemble it in space incase something breaks …the Thing is so overly complicated itll be a miracle if all the flaps, arms, extending poles, all open up perfectly.

  25. Imagine how much the technology has advanced since 2007, will this be the biggest white elephant ever and potentially destroy a generation of work and ambition…will it be worth it?

  26. She sounds so girly. Low T means poor spatial visualization. This trend (of almost lisping) female science presenters is engineered.

  27. Well, March 2021 when this comment was posted is 1yr and 5 months away. That is as close it has ever been to launching that I know of. But I guess anything can happen between then and now.

  28. N.Y.C. Freddy: Comment: I just VIEWED the 'Griffith Observatory' video w. Dr. Eric Smith. (47:45?, duration?) I did not at 'all' LIKE some of what was explained! I suggested there in a comment part – that the Launch (docking – coupling ! ) should be accomplished (perhaps?) in a two phase itinerary venue. [LaGrange Pt.] I believe this proposal as detailed will point toward failure! (My opinion!) 'But' HEY – Who am I – ? Anyhow! I hope that this comment reaches someone who may HAVE an influence w. those involved with the James WEBB launch plan!

  29. It was designed in the 90s, does the design or camera in it change any for better technological improvements since its launch date was pushed back so many times? Or is the satellite that technological advance that it’s future proof for years to come?

  30. The JWT is going to upend many long held beliefs in cosmology. Primarily the age of the universe. The JWT will peer so far back into the void that astronomers will have to date the age of the universe in the TRILLIONS. You heard it here first, kids.

  31. It used to be space probes were named after famous scientists or explorers (Hubble, Magellan, Cassini). The JWST (Just Wait Space Telescope) is such an overbudget, schedule busting boondoggle it is fitting it's named after a government bureaucrat.

  32. Build by nasa? In cooperation with Europe and Canada thank you very much…. small detail you missed 🤷🏻‍♂️🤓

  33. James Webb telescope is a good example of a Lack of Interest combined with Bad Management. Same as Moon Mission postponed several times over 50 years.

  34. If it uses Helium coolant doesn't that mean it's primary mission will have a short finite life like Keppler before it's Hydrogen coolant was depleted?

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