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Space

At Long Last, the World's Most Powerful Space Telescope is Ready To Launch (nationalgeographic.com) 104

Posted by msmash from the closer-look dept.
Decades of tension, debate, and determination have led to this moment, as the James Webb Space Telescope begins its million-mile journey into deep space. From a report: For the world's most advanced space telescope, and the thousands of people who've worked on it over the decades, the starting gun is about to fire. After more than a quarter-century of planning, designing, building, waiting -- and of obsessively testing the most complex space observatory ever assembled -- the mammoth James Webb Space Telescope is scheduled to launch at 7:20 a.m. eastern time on December 25. Whether that launch represents a year-end gift to science or a catastrophic conclusion to 2021 depends on two things: a safe rocket ride into the sky, and the weeks immediately afterward.

For JWST's mission to succeed, the telescope must execute an intricate series of carefully choreographed maneuvers during its first month in space. Even a single misstep could compromise the entire mission. And the telescope must perform its devilishly difficult dance far beyond the reach of human hands, hurtling toward a point in space a million miles away. "This is a high-risk and a very high-payoff program," NASA deputy administrator Pam Melroy said during a call with reporters on December 21. "There are a lot of hard, long weeks ahead, where the telescope has to deploy perfectly."

But the risk is worth the reward. When JWST opens its golden, 21-foot-wide eye, it will transform our view of the cosmos and of ourselves. The telescope's mission is to tell the story of the universe, from a few beats after its radiant, percussive birth through the sweep of cosmic ages until now -- when humans craft machines that are powerful enough to look back to the beginnings of space and time. With an eye that's sensitive enough to see a bumblebee in lunar orbit, the telescope will peer into the primordial murk from which stars, galaxies, and planets emerged, piercing the darkness that has occluded the gaze of other great observatories.
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At Long Last, the World's Most Powerful Space Telescope is Ready To Launch More

At Long Last, the World's Most Powerful Space Telescope is Ready To Launch

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  • Ready To Launch

    Don't count your chickens until they've actually been launched into space (or something like that).
    There's still plenty of time for this to get delayed *again*...

    • Re:Ya, but ... (Score:5, Informative)

      by Tablizer ( 95088 ) on Thursday December 23, 2021 @03:30PM (#62110283) Journal

      Delays worry me less than something going wrong in space. This is a highly complex structure and nothing comparable has been launched before. It's like an umbrella factory had a love child with the origami club.

      In my opinion it should be launched with a "poke & hook bot" to help unjam sub-substructures per the unfurling process. Or at least have an aide-bot plan ready to execute if it gets jammed.

      The Galileo probe had an antenna unfurling glitch that left the primary antenna useless, greatly reducing bandwidth. Galileo was still a successful mission because most its experiments were not bandwidth intensive. Still, it couldn't do heavy imaging. For example, it probably missed discovering and mapping icy plumes squirting from Europa because the imaging limit. The Cassini probe discovered similar at Enceladus (Saturn) because it took and sent a lot of exploratory images. Hubble eventually discovered Europa's venting.

      But there probably is no equivalent "half mode" with the Webb scope; it's mostly all-or-nothing in terms of unfurling. The optics won't line up if the unfurling doesn't go near perfect, which is necessary to function as a "telescope".

      • Sounds like after the launch itself we have about a month of ongoing drama if all goes well:

        The first thing JWST must do right after launch is deploy its solar panel to start gathering energy from the Sun needed to power the entire spacecraft. During its next day in space, it'll deploy its high-gain antenna needed to communicate with Earth. After that, the really wild reverse origami begins. JWST will change its shape and start to deploy its delicate sunshield, a process that is set to last for days. If tha

      • it should be launched with a "poke & hook bot"

        I think that can be ordered on the Adam & Eve website ... :-)

      • Delays worry me less than something going wrong in space.

        Agreed. I was just noting that there have been a LOT of delays on the ground for this so far, so it being "ready to launch" seems like something to take with a grain of salt. It will be interesting to watch this thing go through its procedures and come to life after launch.

      • Re: (Score:2)

        by ceoyoyo ( 59147 )

        The optics are reasonably easy. It's a rigid structure, just a couple hinges. And the individual mirror segments can each independently vary their curvature and aim, purposely to avoid a situation where something gets jostled out of alignment.

        The sun shield though... getting multiple giant layers of kapton to fold out just right....

      • For example, it probably missed discovering and mapping icy plumes squirting from Europa because the imaging limit.

        Are we sure that wasnâ(TM)t just the influence of the monolith?

      • Re: (Score:2)

        by Pascoea ( 968200 )
        I kind of wonder, would it be able to do anything useful if the left or right mirror "wings" can't lock into place? You'd have to assume it could still get some images. I'd guess that if the sunshade doesn't unfurl correctly it's 100% game over.

      • Re: "to help unjam sub-substructures"

        Too many subs, I intended one.

    • Re: (Score:2)

      by Pascoea ( 968200 )
      I'll take delay over RUD any day.

    • There's still plenty of time for this to get delayed *again*...

      If anything goes wrong, the people who built this thing get even more money.

      Think about it.

      Thats why we spent billions of dollars for capabilities a handful of million dollar satellites could have also accomplished, just not in one satellite.

      When pork gets lit on fire, some of it becomes bacon.

  • Cue the "ice storm" technical difficulties in the last fifteen minutes before the launch. were they required to have it up in this calendar year? seems like an odd window to pick..

  • Did they give it an eye exam? (Score:3)

    by quonset ( 4839537 ) on Thursday December 23, 2021 @03:10PM (#62110229)

    And the telescope must perform its devilishly difficult dance far beyond the reach of human hands

    Cause, you know, the last time a big telescope was sent up it needed a corrective lens to properly work.

    • Re:Did they give it an eye exam? (Score:5, Informative)

      by Ol Olsoc ( 1175323 ) on Thursday December 23, 2021 @03:41PM (#62110315)

      And the telescope must perform its devilishly difficult dance far beyond the reach of human hands

      Cause, you know, the last time a big telescope was sent up it needed a corrective lens to properly work.

      The Hubble was such a strange story, of a mirror precisely figured to incredible accuracy. Just wrong. Where an amateur Telescope maker could hav seen the mistake with a home made Foucault tester.

      Capped off with a spare mirror ground correctly but sitting in a warehouse. Meanwhile, I find the wait until Christmas morning's launch incredibly nerve wracking.

      We're going to find out who the geeks are. I'll be rising at 6, just like when I was a kid.

      • Re: (Score:1)

        by Tablizer ( 95088 )

        an amateur Telescope maker could hav seen the mistake with a home made Foucault tester.

        I believe it happened in part because some of it was still classified, being it's spy-scope technology.

    • We spent billions of dollars to send up a big eye in the sky only to realize:

      HOLY CRAP! IT REALLY WAS TURTLES ALL THE WAY DOWN! (lol)

    • Did they give it an eye exam?

      Gee, I bet they didn't think of that! /s

      "JWST's optical design is a three-mirror anastigmat,[41] which makes use of curved secondary and tertiary mirrors to deliver images that are free from optical aberrations over a wide field. In addition, there is a fine steering mirror which can adjust its position many times per second to provide image stabilization."

    • Re: (Score:2)

      by AmiMoJo ( 196126 )

      There will be no fixing this one, given it's very far out orbit and the lack of any suitable vehicles to even do it in LEO anymore.

      Probably the biggest risk is that it doesn't unfold properly. It is folded up to fit in the launch vehicle, and then needs to unfurl several components in a very specific sequence. The motors could fail, the position sensors could fail, the control system could fail, or they could leave a strap on it like they did back in the Mercury days. Fingers crossed, touch wood etc.

    • Re: (Score:3)

      by marcle ( 1575627 )

      Not gonna subscribe to a link that says nothing we don't already know about the Webb telescope. Slashdot should know better than to link to paywalls.

  • For the price this better discover more than LHC (Score:3)

    by iamnotx0r ( 7683968 ) on Thursday December 23, 2021 @04:36PM (#62110471)
    The LHC cost 4.75 billion.
    A modern US Aircraft Carrier costs 13.3 billion.

    The James Webb, 11.5 billion.

    Amazing the price.
    • It is a staggering amount of money.

      A carrier with its air wing does have a recurring cost of over $2B / year to operate. And we have 11 of them.

      • There would have to be at least a 20% chance that the Webb will fail. Either on launch or deployment.

        A lot of eggs in one basket.

        But the real comparison is not an aircraft carrier, which is arguably useful, but the Space Stations, which serves no purpose whatsoever. Well over $100 billion.

        • But the real comparison is not an aircraft carrier, which is arguably useful, but the Space Stations, which serves no purpose whatsoever. Well over $100 billion.

          The usefulness of the ISS is in gaining experience with long-tern human stays in microgravity. We have needed it to determine whether human survival in space requiures simulated gravity. If we're going to mine asteroids, or deflect asteroids from hitting Earth, we absolutely need to find this out.

          • Microgravity studies were done long ago on the Mir. Nobody stays on the space station for years at a time.

            As for other long range missions, humans are already obsolete technology. We have had rovers on Mars for a long time now.

        • Re: (Score:2)

          by Pascoea ( 968200 )

          which serves no purpose whatsoever

          Much like the pile of grey matter between your ears.

    • Define "more". Are you counting individual discoveries? Are you considering the complexity? Are we going for quantity or quality? And what about the relative importance to individual theories?

      The LHC is known for being a $4.75bn experiment to find the Higgs-Boson, but did you know it's found over 60 other particles in various experiments as well? Heck only 3 months ago did they finally manage to measure the mass of the W boson. Despite it being in the popular news only twice (once discovering the higgs, an

      • Hubble is able to see light frequencies that we can see on earth, but it can pick up a much more faint signal.

        James Webb will be able to see light frequency ranges that don't make it to earth at all.

      • >The LHC is known for being a $4.75bn experiment to find the Higgs-Boson
        And the supersymmetric particles. They didn't turn up though, which is a more interesting result than the Higgs Boson, which was expected to be found.

    • We should spend *more* on science. Think of all recorded history, what has propelled civilization forward?
      Leaders, actors, artists, sport starts, merchants, soldiers, farmers? nope
      Businessmen, writers and explorers? somewhat
      Scientists? almost all of it
    • Science is expensive.
      When you speak of the cost of an aircraft carrier, you're ignoring the money spent on the development of its systems.
      The Gerald R. Ford, for example, coming in at $12.8b sticker price, cost $4.7b in R&D not included in that cost.

      Even at $11.5b, JWST comes in $5b cheaper, adjusted for inflation, than the HST.

      I do love the LHC part though. A stationary ring dug in the dirt and lined with superconducting magnets with no moving parts. Seems equivalent.

  • Holding my breath ... (Score:5, Informative)

    by kbahey ( 102895 ) on Thursday December 23, 2021 @04:47PM (#62110517) Homepage

    I will be holding my breath for the several weeks it takes to unfurl, and go into the L2 orbit.

    Here are some videos that show how an awesome piece of engineering this is, and how much science it will do:

    Relatively short videos:

    Launchpad Astronomy [youtube.com]

    Mike Merrifield [youtube.com]

    Real Engineering [youtube.com]

    Longer videos

    Presentation by project scientist [youtube.com]

    Another by a program scientist [youtube.com]

  • Wadda ya waitin' for, Christmas? - Duke Nukem

  • Things that can go wrong (Score:4, Informative)

    by jd ( 1658 ) <imipakNO@SPAMyahoo.com> on Thursday December 23, 2021 @05:01PM (#62110549) Homepage Journal

    1. Arianne fails. Rockets do fail.
    2. The antenna jams.
    3. The solar panels jam.
    4. The sensors jam.
    5. Anti-science freaks invade the site.
    6. A political crisis in America results in the program being defunded.
    7. The telescope collides with space junk.
    8. Weather postpones the launch for a significant period of time.
    9. Assembly error of sensors causes a catastrophic failure.
    10. Programming errors (such as units mismatch) cause a catastrophic failure.
    11. Components used have a MTBF of 20 years.

    • If each component has a 99% chance of working perfectly, but there are 1000 components, things would not look good.

      Let us hope and pray. It will probably be fine. Probably.

    • #5 It's fair to call Amazon tribes anti-science or at least anti-tech, but they've never shown any inclination to invade the Guiana Space Centre.

      #6 is no longer a problem, the ESA would gladly assume all the ongoing operating costs in order to claim all the observation time. They're already paying for the launch.

      #7 is extremely unlikely because there's no space junk anywhere near the destination location and space junk is too well-mapped for a collision during launch.

      #8 is not really possible, weather forec

      • #5 It's fair to call Amazon tribes anti-science or at least anti-tech, but they've never shown any inclination to invade the Guiana Space Centre.

        But because the JWST is launching from an EU site, there is a chance of terrorist activity from European Greens, especially from a Green-native alliance. Here is a US example of what can happen:
        https://en.wikipedia.org/wiki/... [wikipedia.org]

    • 11. Components used have a MTBF of 20 years.

      First of all they are using high-reliability components which have MTTF in excess of 1000 years. Secondly, MTTF concerns components powered on, an I doubt JWST was powered on during those 20 years. Finally, those components are also hermetic, which protects them from most storage-induced degradation.

    • 1. Ariane is one of the most reliable launchers.
      5. They'll have to deal with the Gendarmerie and the French Foreign Legion.

      JWST is the most extensively tested spacecraft in history, to reduce the chance of 2, 3, 4, 9 and 10.

  • "With an eye that's sensitive enough to see a bumblebee in lunar orbit," - That should be enough resolution to see even the footprints in the dust. Or would visible light not have enough resolution because of it's wavelength?

    • JWST will not be able to image the Moon because from its location, Earth/Moon will be in the same direction as the Sun and therefore behind the sun shield. Pointing the telescope toward the Sun would probably fry it.

  • People keep saying it is a successor to HST.
    The HST can see optical as well as probably IR.
    Can Webb see all optical and is just more precise?
    Or does it miss some optical and therefore can't see features the HST can?

    • It is 2021.
      If you can type those questions into /. - you as well can type them into google.

    • Re:can it see optical (Score:5, Informative)

      by thegarbz ( 1787294 ) on Thursday December 23, 2021 @07:10PM (#62110851)

      It's more complex than that. Objects that are further away suffer from what is known as red-shift. What you call optical (I assume you mean visual, as in what the eye can see), is actually no longer within our visual sensitivity once it is a sufficient distance away. The standard visual colour palate isn't all that interesting for astronomy. Most of what you see is actually false colour images to show that which we can't see.

      For example, here's the Pillars of Creation as we would see it (if our eyes were colour sensitive in the dark) https://imgur.com/a/5VTHPqF [imgur.com]
      Here's what they look like (zoomed out) with a camera highly sensitive to infrared: https://imgur.com/a/T8ueWG1 [imgur.com]
      And here's what Hubble produced: https://stsci-opo.org/STScI-01... [stsci-opo.org] a fantastic false colour assigning green to a hydrogen emission spectrum, sulfur emission to blue, and oxygen emissions to red and then colour balancing the result so it doesn't look completely green.

      Space is a lie told to us by machines :-)

  • Is this some sort of risk management thing?

    • Is this some sort of risk management thing?

      Risk Strategies 101:
      1) Never try to use Australia as a base from which to attack the rest of the world.
      2) Only try to hold Kamchatca if you are strong enough to hold all 3 fronts.
      3) Hold the Americas (both ends) and you win.

    • 1) It's an international project. The Ariane 5 and launch services are part of the European contribution.

      2) Given the production schedule, the first SLS that would be available outside the Artemis project would be delivered three or four years from now.

      3) Even if the SLS were actually available now, the cost per launch is something over $2B, an order of magnitude more than the Ariane 5.

      4) The ULA has notified NASA that they will barely be able to deliver the SLS vehicles to cover the Artemis launches

  • I wish everyone involved with the telescope well, and hope that everything goes smoothly.

    When it does, I wouldn't mind some telescope time on Hubble :)

  • I thought lunar orbit would be a safe place to hide my bumblebee.

  • But, given its track record, I have my reservations. And I still resent the fact that it is named after a politically-appointed bureaucrat, who knew nothing and did not care at all about astronomy. It is an insult to the many astronomers who, throughout history, and unlike the mindless political minion that Webb was, have contributed mightily to the advancement of astronomy.
  • Grand sights await.

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