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The Future of Astronomy: NASA's James Webb Space Telescope

Posted by timothy on from the pretty-bauble-in-itself dept.

An anonymous reader writes: In 1990, the Hubble Space Telescope was launched and deployed, becoming the first space-based observatory. In the years since, many others have followed, covering the entire electromagnetic spectrum, but with nothing superseding Hubble over the wavelengths it covers. That will all change with the James Webb Space Telescope, currently on schedule and almost ready for its October 2018 launch date. The science instruments are all complete, the final mirrors are being inserted into the optical assembly, the sunshield (a new, innovative component) is almost complete, and then it just needs assembly and launch. When it's all said and done, JWST will be orders of magnitude greater than all the other observatories that came before, and will finally allow us to truly see the first stars, galaxies and quasars in the Universe, not limited by the obscuring neutral gas that currently blocks our view with other observatories.

22 of 117 comments (clear)

  1. Finally be able to really see our own galaxy by jfdavis668 · · Score: 3, Insightful

    The Hubble Space Telescope was great looking outside the galaxy, but galactic dust blocks our view of our own galaxy. It will be great to finally be able to peer through the dust and see the structure of the Milky Way.

    1. Re:Finally be able to really see our own galaxy by 110010001000 · · Score: 2, Funny

      The shots of Uranus are going to be stunning!

    2. Re:Finally be able to really see our own galaxy by smittyoneeach · · Score: 2

      Let's keep things Plutonic.

      --
      Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
    3. Re:Finally be able to really see our own galaxy by smittyoneeach · · Score: 2

      Sounds like someone needs a Hg.

      --
      Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
    4. Re:Finally be able to really see our own galaxy by wonkey_monkey · · Score: 2

      This Ceres of puns really Mars my enjoyment of this story.

      --
      systemd is Roko's Basilisk.
  2. fRO0ST MALAW1WARE by Hognoxious · · Score: 5, Insightful

    Don't click the link. It's forbes. it won't work uunless you disable adblock, and if you do it'll install malware.

    (It's Ethan, the goatblower with the shaved head and the beard, if you hadn't guessed)

    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."
  3. StartsWithABang by 110010001000 · · Score: 4, Informative

    Ethan, you can't fool us anymore. We know you submitted this. DON'T VISIT THE LINK. His blog is full of malware ads and they require you to remove your adblocker. You have been warned!

  4. Site blocked - Forbes by Ecuador · · Score: 4, Insightful

    Why would you post a link to Forbes? It gives me some crap about disabling my ad-blocker (yeah, right) and not letting me see the content unless I do so. As far as I'm concerned it is the same as paywalled. Either find another source or don't post it. Oh, right, it's Timmy.

    --
    Violence is the last refuge of the incompetent. Polar Scope Align for iOS
  5. Not superseding Hubble by DarkBlackFox · · Score: 4, Informative

    "In the years since, many others have followed, covering the entire electromagnetic spectrum, but with nothing superseding Hubble over the wavelengths it covers. That will all change with the James Webb Space Telescope, currently on schedule and almost ready for its October 2018 launch date."

    This is not entirely accurate. JWST is primarily infrared- it won't cover the full visible spectrum. Hubble will still be required to see anything below yellow/green wavelengths, including blue down through ultraviolet, where JWST can't see at all. It will certainly let us see farther, and through the dust, but it's not the be all end all of space telescopes.

  6. Check the Focus! by sycodon · · Score: 2

    Did anyone think to point this thing at something on the ground and check the focus?

    Because they didn't think to do that for the Hubble.

    --
    When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
    1. Re:Check the Focus! by amicusNYCL · · Score: 2

      If the JWST can focus on something on the ground a few meters from it then I'm not sure that the focus is set correctly for when it's in space.

      --
      "Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
    2. Re:Check the Focus! by stevelinton · · Score: 3, Insightful

      Their calibration involved a reference point for one of the lasers that had to be precisely positioned. This was done by having a rigid metal bar with a polished end, covered by a very black cap with a pinhole in it. The point on the end of the bar visible through the pinhole was meant to be the reference.

      Unfortunately someone scratched the end of the cap a little and no one noticed. The shiny metal in one of the scratches got picked up as the reference instead of the pinhole. As a result it was too close to the mirror by the thickness of the cap (a millimeter or so). That was enough to lead them to carefully polish the mirror to slightly the wrong shape.

      They did, I believe, ignore contradictory results from another basically much less accurate method of testing the mirror, since the laser was giving consistent results and was the superior method.

    3. Re:Check the Focus! by ClickOnThis · · Score: 4, Informative

      For Hubble someone forgot to account for change in shape of the lens due to gravity

      No, the problem was caused by one of Perkin-Elmer's testing devices having been assembled incorrectly.

      https://en.wikipedia.org/wiki/...

      --
      If it weren't for deadlines, nothing would be late.
    4. Re:Check the Focus! by vtcodger · · Score: 4, Interesting

      Quite a lot of speculative fiction in this thread. In point of fact the US (and Russia and ... probably others) had extensive experience with big telescopes in space pointed at the Earth by the time Hubble was launched. Heck Google maps satellite view can resolve cars in our driveway an a barbeque on our deck. It's a safe bet that the intelligence folk, now and then, could/can do better. Most likely lots better

      (BTW, my understanding is that you need very complex adaptive optics to get clear views of small stuff on the surface from space. The optics correct for minor atmospheric issues. Same issues that make stars appear to twinkle.)

      I didn't work on Hubble's optics (no one in their right mind would put me to work on optics) and it's not unlikely that I wouldn't be able to talk about exactly what went wrong even if I knew because of the probable overlap with highly classified stuff that is probably still classified. But I suspect it was probably a simple screwup. If you're interested in the official story -- which surely could be true -- see http://www.cio.com.au/article/... (Bottom line; a small procedural error during calibration resulted in the optical elements in Hubble being ever so slightly misaligned.)

      Here's a link to two decade old intelligence photos leaked in 1997. http://fas.org/irp/imint/kh-12...

      BTW since no one else is likely to mention it, the Webb observatory is about a decade late and 400% or so over budget. Moreover, it's not clear that its imaging in the visual spectrum will be much if any better than the big ground based telescopes like this one https://en.wikipedia.org/wiki/... scheduled for about a decade from now. If nothing else the EELT is likely to be a good deal easier to tweak/repair/improve than a telescope meandering around hundreds of thousands of km from earth.

      (The IR portion of the Webb device is clearly worthwhile although one might question if it is eight billion dollars worth of worthwhile).

      I apologize for being grumpy. But I'm kind of tired of listening to hype, fiction and misrepresentation, and of folks continuing to buy into it.

      I appear to be surrounded by slow learners.

      --
      You can't see ANYTHING from a car, You've got to get out of the goddamned contraption and walk...Edward Abbey
    5. Re:Check the Focus! by ClickOnThis · · Score: 2

      (BTW, my understanding is that you need very complex adaptive optics to get clear views of small stuff on the surface from space. The optics correct for minor atmospheric issues. Same issues that make stars appear to twinkle.)

      Actually, the problem of atmospheric turbulence causing blur is not as bad looking at the Earth from space as it is the other way around. The biggest problem is rotating the large telescope required quickly enough to track what you're looking at. There's a great discussion of the problem here.

      --
      If it weren't for deadlines, nothing would be late.
  7. the word oversight is its own opposite by Pseudonymous+Powers · · Score: 3, Funny

    The Future of Astronomy: NASA's James Webb Space Telescope

    You know what they say: The James Webb Space Telescope is the future of astronomy, and it always will be.

  8. Holy Hell by sycodon · · Score: 3, Insightful

    Alright, for all you Pedants out there...

    "Check that the mistake made with the Hubble wasn't made with this one"

    Better?

    Now get a Margarita or something.

    --
    When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
    1. Re:Holy Hell by 110010001000 · · Score: 4, Funny

      The words "margarita" and "pedants" should not be capitalized.

    2. Re:Holy Hell by Mal-2 · · Score: 2

      Margarita is the cleaning lady who sweeps up after hours. He's recommending we all get one for ourselves. Capitalization is perfectly appropriate here. I think Pedants may be a brand of shoes.

      --
      How is the Riemann zeta function like Trump rallies? Both have an endless number of trivial zeros.
  9. Re:Help is Far by CanadianMacFan · · Score: 2

    If anything happens to it then it's gone. We have no way to get to it to fix the telescope. Heck we can't even get to Hubble to fix that even if we wanted to.

  10. Re:Help is Far by amicusNYCL · · Score: 2

    They should start the planning now, because there's probably at least a 10% chance of deployment issues.

    I highly doubt that. On their first try, NASA gently placed a chunk the size of a car on the surface of Mars after dangling it from a crane floating in the sky via rockets. I'm sure they can unfold the telescope.

    --
    "Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
  11. The future of slashdot by thegarbz · · Score: 4, Insightful

    There's only one article I'm interested in: How much is StartsWithABang paying Dice to constantly post every one of his damn blogs? We've got 2 in one day now. Is this a subscription service, or do you pay by the submission? Does it cost extra to hide the poster as an Anonymous Coward? Is the cost proportional to the amount of hate they get?