Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror
×
NASA Space United States Earth Technology

World's Largest Space Telescope Is Complete, Expected To Launch In 2018 (space.com) 156

An anonymous reader quotes a report from Space.com: After more than 20 years of construction, the James Webb Space Telescope (JWST) is complete and, following in-depth testing, the largest-ever space telescope is expected to launch within two years, NASA officials announced today (Nov. 2). NASA Administrator Charles Bolden hosted a news conference to announce the milestone this morning at the agency's Goddard Space Flight Center in Maryland, overlooking the 18 large mirrors that will collect infrared light, sheltered behind a tennis-court-size sun shield. JWST is considered the successor to NASA's iconic Hubble Space Telescope. The telescope will be much more powerful than even Hubble for two main reasons, Mather said at the conference. First, it will be the biggest telescope mirror to fly in space. "You can see this beautiful, gold telescope is seven times the collecting area of the Hubble telescope," Mather said. And second, it is designed to collect infrared light, which Hubble is not very sensitive to. Earth's atmosphere glows in the infrared, so such measurements can't be made from the ground. Hubble emits its own heat, which would obscure infrared readings. JWST will run close to absolute zero in temperature and rest at a point in space called the Lagrange Point 2, which is directly behind Earth from the sun's perspective. That way, Earth can shield the telescope from the sun's infrared emission, and the sun shield can protect the telescope from both bodies' heat. The telescope's infrared view will pierce through obscuring cosmic dust to reveal the universe's first galaxies and spy on newly forming planetary systems. It also will be sensitive enough to analyze the atmospheres of exoplanets that pass in front of their stars, perhaps to search for signs of life, Mather said. The telescope would be able to see a bumblebee a moon's distance away, he added -- both in reflected light and in the body heat the bee emitted. Its mirrors are so smooth that if you stretched the array to the size of the U.S., the hills and valleys of irregularity would be only a few inches high, Mather said.
This discussion has been archived. No new comments can be posted.

World's Largest Space Telescope Is Complete, Expected To Launch In 2018

Comments Filter:
  • by h33t l4x0r ( 4107715 ) on Thursday November 03, 2016 @03:23AM (#53204147)

    You can see this beautiful, gold telescope is seven times the collecting area of the Hubble telescope

    I guess we need to hope president Trump doesn't decide to melt it down to make a new white house toilet.

    • by murdocj ( 543661 )

      It will be renamed the Vladimir Putin Mother Russia telescope. And it will be pointed at earth.

  • So... (Score:5, Insightful)

    by Dutch Gun ( 899105 ) on Thursday November 03, 2016 @03:27AM (#53204155)

    Did they double-check the mirror this time? And compensate for zero-G?

    The testing is particularly high-stakes, because unlike Hubble, which was repaired and refocused in orbit by astronauts, this telescope is not intended to be repaired by humans.

    Yikes. Isn't that sort of like announcing that your vehicle doesn't have seatbelts, so instead you're going to drive very, very carefully? Well, I guess that's not unusual for rocket science.

    "Our lessons learned from the Hubble [telescope incident] were, if you really care about something, you've got to measure it at least twice," Mather added. "And if you don't get the same answer, you'd better figure out why."

    Maybe they should have talked to a carpenter?

    Ok, kidding aside... I really do hope it fares much better than Hubble's initial deployment. There's certainly a lot that can go wrong during development or deployment. But if all goes well, I'm looking forward to seeing what images are captured from the edge of the visible universe.

    • Re:So... (Score:5, Funny)

      by I'm New Around Here ( 1154723 ) on Thursday November 03, 2016 @03:43AM (#53204187)

      I really do hope it fares much better than Hubble's initial deployment. There's certainly a lot that can go wrong during development or deployment. But if all goes well, I'm looking forward to seeing what images are captured from the edge of the visible universe.

      I'm guessing they will see this. (Safe for work.)
      http://i.imgur.com/RrCGkyQ.jpg [imgur.com]

      • by Anonymous Coward

        "http://i.imgur.com/RrCGkyQ.jpg [imgur.com]"

        Oh, you Monoturtleists...
        It's Turtles all the way down.
        Polyturtlism is the only explanation.

    • I'm looking forward to seeing what images are captured from the edge of the visible universe.

      Just some tentacles... and darkness.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      The testing is particularly high-stakes, because unlike Hubble, which was repaired and refocused in orbit by astronauts, this telescope is not intended to be repaired by humans.

      Yikes. Isn't that sort of like announcing that your vehicle doesn't have seatbelts, so instead you're going to drive very, very carefully? Well, I guess that's not unusual for rocket science.

      As mentioned in the summary, the JWT will go to the Lagrangian Point 2 (L2), for the Sun-Earth system. This point is substantially farther than the Moon, so there's no way (at least with current technology) that we're sending men that far. So, it's not that they're betting it all on having it done right this time so we don't need to check. It's just "we're saying goodbye to it, so it better be good."

      • by nojayuk ( 567177 )

        ESA have already put two space observatories, the Herschel infrared telescope and the Planck cosmic microwave background telescope into the L2 location. The JWT is being launched and deployed by ESA so it's not an absolute first for them.

        ESA is paying for the launch and that entitles European scientists access to the instrument and data collected by it.

    • Did they double-check the mirror this time? And compensate for zero-G?

      And remember there's a difference between inches and centimetres.
      Don't forget that on the rocket, the arrows should be pointing upwards.
      Have they tuned the radio link to the correct frequency?

      Luckily this telescope doesn't need parachutes. But they'd better put a screen-wipe in the package in case the mirror gets dusty between now and launch-day.

    • Re:So... (Score:4, Interesting)

      by careysub ( 976506 ) on Thursday November 03, 2016 @11:57AM (#53206155)

      Did they double-check the mirror this time?

      The thing with the Hubble telescope mirror is that engineers at Perkin-Elmer did double-check the mirror with accurate instruments and knew that it was flawed after the figuring was complete. But refiguring it would have cost a lot of money, and delayed delivery (already late), and the improperly assembled null corrector test instrument that was used to figure the mirror was also the contractual acceptance test. So managers and execs and Perkin-Elmer decided to deliver the mirror to NASA anyway, in conformance with contract, without conveying the internal information that the mirror didn't work.

      This echos the situation with the Challenger disaster when management at Thiokol decided (after hours of complaint from a very unhappy NASA) to authorize the cold weather launch despite knowing that disaster was almost certain.

    • ... will be that of a book floating in space.

      It has the title:

      "Postcards from the edge"

    • by ceoyoyo ( 59147 )

      James Webb is designed as a primarily IR telescope. You don't want to park it in low orbit because it would be subject to a lot of IR interference from the planet. So they're putting it at L2, which is a long way away from the planet. Unfortunately we can only really send astronauts to low orbit to fix things. So there's not really much choice about the repairability of the JW.

  • Why so long? (Score:1, Interesting)

    by Whiteox ( 919863 )

    20 years? That's a long time for something that has been done before. Maybe they were extra careful as the website suggests but 20 years is a bit excessive.

    • The funding was cancelled at one point. Lots of political starts and stops.

    • by JWW ( 79176 )

      This thing is all new technology. That's like saying that building a skyscraper takes too long because you already knew how to build a house.

      This thing is an amazing piece of technology.

    • Please point to where "this has been done before" - show me a functioning piece of equipment at the L2 Lagrange point with the same capabilities as this hardware.

      Oh wait, you can't, because it *hasn't* been done before.

      Stop posting when you don't have a clue.

    • It's a good question, but more importantly, if it's ready now, why wait 2 years to launch it?

    • by Anonymous Coward

      The mirrors are extremely well-polished beryllium because its atomic mass is like 1/8th or so of silver. The dust is toxic as fuck so it was a bitch to do. And lots of other things like this kept popping up.

      Apparently though, the JWST is supposed to make the hubble look like a shitty pair of reading glasses so I'm excited as all hell to see what it produces... and that's not even counting the huuuge boon for infrared astronomy.

  • Is this the world's largest only because all the larger ones are already in orbit, and so technically outside of this world?
    • Number of optical telescopes currently in orbit that have a larger mirror than JWST: 0.

  • "The telescope would be able to see a bumblebee a moon's distance away..."

    If only there were bumblebees in space.
  • wonderful
  • now there's an idea

  • According to the project member interviewed on the news.

  • "see a bumblebee a moon's distance away"

    I of course welcome our moon measuring bumblebee overlords...

    Seriously I guess we can get rid of LoC and other forms of measurement including football fields and metric in favor of measuring all lengths of things in terms of moon distances, and volume in terms of bumblebees.

    Seems legit.

  • Hillary's emails. Or perhaps if used close up, her ethical sense.

At work, the authority of a person is inversely proportional to the number of pens that person is carrying.

Working...