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NASA Space Science

Mirrors Finished For James Webb Space Telescope 115

Posted by timothy
from the now-it-can-develop-self-awareness dept.
eldavojohn writes "On August 15th, sendoff ceremonies were held at Ball Aerospace (subcontractor to Northrop Grumman) for the 18 gold-coated, ultrasmooth, 4.2-foot (1.3 meters) hexagonal beryllium primary mirror segments that will comprise the 21.3-foot (6.5 m) primary mirror of the James Webb Space Telescope (JWST). Over 90% of the back material was taken out of these mirrors to make them light enough so that 18 could be launched into space where they must operate at minus 400 degrees Fahrenheit (minus 240 degrees Celsius). The mirrors will be adjusted by computer controlled actuators that are vital to JWST producing high-quality sharp images. The tennis court sized JWST will reside at L2 and is hyped to allow us to see 'back to the beginning of time.' NASA has provided a video of the computer animated metamorphosis with many more videos at the JWST site."
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Mirrors Finished For James Webb Space Telescope

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  • by Anonymous Coward

    We will REALLY be able to see boobies with that thing!

    • We will REALLY be able to see boobies with that thing!

      And then the scientists will find out that the green alien babes they were looking for aren't actually mammals at all and the jig will be up.

  • by TWX (665546) on Tuesday August 21, 2012 @10:16AM (#41067719)
    ...Perkin-Elmer didn't provide any consulting services, especially in the verification process...
    • by Anonymous Coward

      They're now part of the ISR Systems department at Goodrich, which was recently purchased by United Technologies.

      And yes, they still bid and win NASA contracts.

    • I once had a discussion with a director of engineering about being fired for screwing up a design (in jest; a hypothetical "I hope this does't fail" comment). He quickly came back with, "Oh, I wouldn't fire you. Far worse - I'd make you stay on and fix it."

      Smart engineers who have made some rookie mistakes are probably some of the first people you want on a review team. When everything goes perfectly, you don't know how much of your design was genius and how much was luck.

      • by TWX (665546)
        Oh I know, my wife is an engineer and has several long term projects. I don't really know anything about them, and her not talking about them probably adds to her angst, but that's what the engineer's salary is supposed to help offset.

        I cited Perkin-Elmer because they repeatedly ignored fail test results from two tools when one tool gave a pass, and that one tool was later identified as being assembled incorrectly so its optics were wrong. They seemingly never questioned that tool's results or had it c
  • by bruce_the_loon (856617) on Tuesday August 21, 2012 @10:17AM (#41067729) Homepage

    Please tell me they have been collimated properly and we aren't going to get another Hubble problem, this time at L2 with no hopes of a monocle to fix it.

  • hopefully they polished this one well enough...

  • by Errol backfiring (1280012) on Tuesday August 21, 2012 @10:20AM (#41067773) Journal

    ... see back to the beginning of time

    so they finally see the hand of the Maker:

    Sorry for the inconvenience.

  • Stuff like this is the reason i frequent Slashdot.
  • When they add in the new power supply, will it use berryllium spheres?

  • by Picass0 (147474) on Tuesday August 21, 2012 @10:35AM (#41067911) Homepage Journal

    During Hubble's deployment a solar panel failed to fully unfold. An astronaut needed to manually extend the panel or Hubble would not have the power to operate. Hubble famously needed a "set of glasses" to correct for a deformation in it's mirror. This was accomplished with a space shuttle mission. In the years that followed Hubble needed gyroscopes replaced and has received upgrade packages to extend it's capabilities.

    Webb will be four times further away from Earth than the distance between the Earth and Moon. That will make any effort to repair it more risky than an Apollo moon mission. Webb was almost cancelled for budget reasons. It's unlikely a rescue mission would be conducted if something were to go wrong.

    I can't wait to see what a telescope more powerful than Hubble can do. I hope everything goes according to plan.

    • Re: (Score:3, Insightful)

      by martinux (1742570)

      NASA has learned a lot from all of their work up until now. Consider the spectacular success in getting Curiosity onto Mars - a remarkably complex and audacious plan.

      Testing methods, materials and technology has come a long way; it's not a guarantee that everything will go without a hitch but I'm optimisitic.

    • Thousands of satellites have been launched on unmanned rockets and have done fine without human intervention.

      • by Picass0 (147474)

        I'm aware, but most of them extend a dish or make a minimal configuration change once in orbit. Few of them are folded like complex origami into a rocket nose.

        I want this to work, I'm just expressing a concern.

        • I'm aware, but most of them extend a dish or make a minimal configuration change once in orbit. Few of them are folded like complex origami into a rocket nose.

          I want this to work, I'm just expressing a concern.

          It does occur to me that it would not be so far away that we couldn't launch a robotic vehicle with manipulators to do maintenance on it.

    • by PhxBlue (562201)

      Webb will be four times further away from Earth than the distance between the Earth and Moon. That will make any effort to repair it more risky than an Apollo moon mission. Webb was almost cancelled for budget reasons. It's unlikely a rescue mission would be conducted if something were to go wrong.

      I think robotics has advanced to the point where we could engineer and send up an unmanned repair vehicle if we had to. Hopefully, we won't have to. :)

    • by Rich0 (548339)

      How much of the cost of the Webb was actually construction? I never understood all the hubble repair missions and such - just build a few more of them and launch them.

      I suspect that 90% of the cost is in the design/etc. Sure, the mirror has to cost a pretty penny, but after you have the rigs all designed to grind it out, why not just start them on a second mirror the day after the first is removed? If something goes wrong with the first telescope you have a spare, and if not, well, then you get to do twi

  • by RenHoek (101570) on Tuesday August 21, 2012 @10:37AM (#41067935) Homepage

    Guys, really? Fahrenheit? In a science article? On an international website?

    I don't even advocate the usage of Celcius in this case, so why not use 33 degrees Kelvin? This at least give us _some_ idea of how close to absolute zero we are. Otherwise, why not use 'near absolute zero' and leave out the numbers completely?

    </getoffmylawn>

    • So Fahrenheit is right out but tennis courts are a valid area unit?

      Jeez, somebody whizzed on the electric fence [youtube.com] last night.
    • by blueturffan (867705) on Tuesday August 21, 2012 @10:54AM (#41068123)

      Guys, really? Fahrenheit? In a science article? On an international website?

      I don't even advocate the usage of Celcius in this case, so why not use 33 degrees Kelvin? This at least give us _some_ idea of how close to absolute zero we are. Otherwise, why not use 'near absolute zero' and leave out the numbers completely?

      </getoffmylawn>

      degrees Kelvin you say? In a comment to a science article?

    • by Anonymous Coward

      If you're going to complain, complain about the use of "minus" as a unary operator.

      It's *negative*. Minus is subtraction.
      Pet Peeve!

      At least with F and C they're accurate if unconventional.
      (Aside: What? no Rankine love?)

    • by Anonymous Coward

      Guys, really? Fahrenheit? ... On an international website?

      It's not an international website. It's an American website. The fact that you can access it from outside the US is great and all, and I welcome everyone to this community warmly. However, I welcome everyone to the community warmly in the very same way that the grocery store down my street welcomes foreign visitors. They'll sell you anything you want, treat you the same as they treat all their American customers, but don't go and get all indignant that they have no employees who speak Finnish. This web

    • by Dishevel (1105119)

      On an international website?

      From an old slashdot FAQ.

      Slashdot is U.S.-centric. We readily admit this, and really don't see it as a problem. Slashdot is run by Americans, after all, and the vast majority of our readership is in the U.S. We're certainly not opposed to doing more international stories, but we don't have any formal plans for making that happen. All we can really tell you is that if you're outside the U.S. and you have news, submit it, and if it looks interesting, we'll post it.

    • by cellocgw (617879)

      Guys, really? Fahrenheit? In a science article? On an international website?

      I don't even advocate the usage of Celcius in this case, so why not use 33 degrees Kelvin?

      For one thing, there's no such thing as a "degree Kelvin." Look it up.

  • by Trepidity (597) <delirium-slashdot@h a c k i sh.org> on Tuesday August 21, 2012 @10:39AM (#41067961)

    Wish it had been named after an astronomer, like the Hubble [wikipedia.org] was, not a NASA administrator.

  • a solid xenon-halogen laser and a ginormous popcorn ball!

  • by sageres (561626) on Tuesday August 21, 2012 @10:59AM (#41068177)

    It is very unfortunate that JWST means the end if Hubble. JWST provides only infrared spectrum (and we already have seperate telescopes that do infraded and x-ray), while Hubble does ultraviolet and optical. Servicing Mission 4 was under the thread of being canceled, however even though it is completed, all the finances are now invested into JWST, so SM4 was the last mission to the Hubble.

    • And there are no more. Fortunately they squeezed in one last servicing mission among the Columbia disaster protocols and ISS completion. That may keep Hubble going until 2020. Probably will still be a gap until Webb is operational. Gyro failures are the most likely cause of Hubble end.
      • by M1FCJ (586251)

        Why bother when it is not necessary. Ground-based scopes can do visual band perfectly fine. IR and UV have to be outside the atmosphere apart from some very narrow windows. Saying that, JWST costs too much and not worth it. We would have got a lot more science out of a couple of smaller IR scopes and loads of ground based stuff where it's multiple magnitudes of order cheaper and they're shutting left and right because there's no money left.

    • by ogre7299 (229737) <jjtobin@@@umich...edu> on Tuesday August 21, 2012 @12:15PM (#41069133)

      While there have been other telescopes that observed in the infrared, JWST will have a mirror 6x larger than the prevous space-based telescopes that operate or have operated at the same wavelengths (0.8 to 24 microns). This means that JWST will have a factor of 6 better resolution than previous telescopes and be incredibly more sensitive due to the larger collecting area. Ground-based telescopes cannot compete with JWST because of the sky brightness in the infrared making sensitive observations very time consuming. The science drivers of JWST are primarily the high-redshift universe, that is galaxies that were formed shortly after the big bang. This is something Hubble cannot do since it is not infrared optimized (the telescope is quite warm compare to JWST's operating temperature) and has too small of an aperture for the resolution needed.

      The lack of future Hubble servicing has a lot to do with the retirement of the Space Shuttles, the only platform that can be used to service HST. Hubble will be kept going as long as possible since it is still doing outstanding science. In the 2020s it is hoped to launch an 8m class optical-uv telescope to truly replace Hubble.

  • This could be the seed of future Hubble telescope. It would still cost a lot to build a telescope around them and launch them.
  • He looked out the porthole at the new telescope whose gathering disc dwarfed his ship.

    "That's one big-ass mirror!", Tom Swift reflected.

  • by wonkey_monkey (2592601) on Tuesday August 21, 2012 @12:17PM (#41069153) Homepage
    What are the chances of a mirror getting hit by a micro (or not so micro) meteorite out there? Pretty slim, obviously, or they wouldn't bother, but seeing that animation makes it look pretty unprotected.
  • Let's pretend that the people who write budgets are the only people on this planet with any common sense.

    Then we can judge everything based on whether it overran its budget, without consideration of any other criteria.

    Sounds strange? Read the comments above!

  • I hope they calibrated the testing equipment.

    I seem to remember that the Hubble mirror passed all the tests, but that the test equipment wasn't calibrated correctly.

  • You know what would have REALLY been able to "see back to the beginning of time"? A proper gravitational observatory like the LISA/Pathfinder project, which would have used three satellites to measure fluxuations in space-time less than the width of an atomic nucleus. It was planned to be operational by 2015 and would have been able to "see" better and farther than light-based telescopes.

    But I probably will never see anything as cool as that, because it lost funding when the Webb sucked up all the oxygen in

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