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Space Science Technology

World's Largest Digital Camera Project Passes Critical Milestone 73

An anonymous reader writes in with a link about the progress of one of the coolest astronomy projects around. "A 3.2 billion-pixel digital camera designed by SLAC National Accelerator Laboratory is now one step closer to reality. The Large Synoptic Survey Telescope camera, which will capture the widest, fastest and deepest view of the night sky ever observed, has received 'Critical Decision 1' approval by the U.S. Department of Energy (DOE) to move into the next stage of the project. The Large Synoptic Survey Telescope (LSST) will survey the entire visible sky every week, creating an unprecedented public archive of data – about 6 million gigabytes per year, the equivalent of shooting roughly 800,000 images with a regular eight-megapixel digital camera every night, but of much higher quality and scientific value. Its deep and frequent cosmic vistas will help answer critical questions about the nature of dark energy and dark matter and aid studies of near-Earth asteroids, Kuiper belt objects, the structure of our galaxy and many other areas of astronomy and fundamental physics."
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World's Largest Digital Camera Project Passes Critical Milestone

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  • Sad for NASA (Score:5, Insightful)

    by treeves ( 963993 ) on Wednesday April 25, 2012 @04:06PM (#39799297) Homepage Journal

    that DOE is doing this and not NASA.

    • Re:Sad for NASA (Score:5, Informative)

      by Jeng ( 926980 ) on Wednesday April 25, 2012 @04:23PM (#39799479)

      It is politically beneficial it for politicians to cut NASA's funding, but other agencies want these projects done so they do it because they actually have the funding to do it.

      So yea, it is sad for NASA, but it's not NASA's fault.

    • Re: (Score:2, Flamebait)

      by ArsonSmith ( 13997 )

      NASA's to worried about global warming and reducing energy usage for the US.

      • Not sure why you think they're "to" worried about those things. NASA's whole job is developing technology and processes for a long-term human presence in space, and environmental science and sustainability are crucial elements of that goal.
      • I thought they were spending all their time now making Muslims feel better [] about themselves.

    • Sad for NASA that DOE is doing this and not NASA.

      It's a ground-based telescope. Where exactly would NASA come in?

      Also: Don't start your sentences in the subject field, it's bloody annoying.

    • Well, at .003 million megapixels, they've got a long way to go to catch up to the 5 million megapixel cameras for sale at Best Buy, according to the illiterate, innumerate salespeople.

  • In LOC, please (Score:5, Insightful)

    by Overzeetop ( 214511 ) on Wednesday April 25, 2012 @04:09PM (#39799325) Journal

    I hate when articles can't use standard units. Are petabytes, exabytes, zettabytes not really usable yet?

    • by RenderSeven ( 938535 ) on Wednesday April 25, 2012 @04:16PM (#39799407)
      Most people think that 'petabytes' is somehow related to child pornography, 'exabytes' is a skin disease, and 'zettabytes' is a video game character.
    • by Anonymous Coward

      Authors should assume they can use any prefix that is currently available for civilian hard drives. "6 thousand terabytes per year" is somewhat workable. A better term would be "500 terabytes each month."

      Also, 3.2 gigapixels! []

      • I often create canvas prints of family photos. Mainstream 3.2 gigapixel pics means I'll be photoshopping another 1.1 gigapixels of zits, fat, and moles OUT, another 1.1 gigapixels of hair, tanned skin, and white teeth IN, and just plain giving up on the remaining gigapixel (meh, it's probably just the dog or grandma anyway).

        God it's hard to make people prettier than they are in real life; exponentially so when they're high-rez people. Maybe I'll ONLY make canvas prints out of LSST space photos. Uh....
  • by Anonymous Coward

    I thought we had terabytes and above for "zillions of gigabytes"?

    • But then again.. Who do you know, that uses Gg or Giga Gram, instead of 'Thousand Tons'?

      • Kiloton? Even megaton is fairly mainstream. I know the mainstream use is for imperial tons of TNT, but there is such a thing as a metric ton.
  • by DadLeopard ( 1290796 ) on Wednesday April 25, 2012 @04:15PM (#39799391)
    I would think that it would also help track down just about everything in the Solar system, when using successive pictures of the same portion of the sky in a "Blinker" box or whatever they use in place of that now. Dark matter is all fine and dandy, but the location and trajectory of Asteroids and comets are of a different degree of importance!
    • by Jeng ( 926980 ) on Wednesday April 25, 2012 @05:17PM (#39800059)

      The problem is that even with this camera, if what you are looking at is not illuminated then it will not be visible (think asteroid in shadow of moon).

      So basically the worlds largest digital camera needs the worlds largest camera flash. I would suggest using a low yield nuclear warhead, but there would be a few issues with that.

      • So basically the worlds largest digital camera needs the worlds largest camera flash. I would suggest using a low yield nuclear warhead, but there would be a few issues with that.

        Make that two nuclear warheads to avoid red eye.

      • by wisebabo ( 638845 ) on Wednesday April 25, 2012 @11:04PM (#39802823) Journal

        In one of his short stories, (I believe) after a near miss by an earth grazing asteroid (sliced through the upper atmosphere over a major city), a very large (gigaton) bomb is detonated in earth's orbit in a position diametrically opposed to the earth. The resulting "flash" resulted in a radar pulse (remember that was Clarke's early training in WWII) that was used to illuminate all the objects in the solar system. This was recorded and catalogued.

        Decades later, an extra-terrestrial signal is recorded from another star system. After a quick calculation, it is apparent that the aliens, upon detecting the flash of this giga-bomb, quickly responded with a reply aimed at our solar system.

        • Sir Arthur may have proposed it, but he got the science badly wrong.

          Not only would such a bomb not produce a flash (the flash is a product of the bomb's reactions with the atmosphere) or a radar pulse of any kind, but even if it did - it would have to be in the tens or hundreds of gigatons to exceed the illumination available from the sun, and would only be useful for 1 AU or so from the bomb.

      • If they took pictures during the day they wouldn't need a flash. The Sun has a lot more output than any terrestrial bomb flash.
      • I'm Pretty sure that most of the objects in the Solar System are not in the shadow of another object more than a minuscule portion of the time! So what didn't show on the first pic will show on the next, unless time between pics coincidently coincides with the orbital periodicity of the object, the probablitity of this continuing for a long period of time is vanishingly small! Now a very low albedo on the other hand, will make it hard to see some things!
    • by ks*nut ( 985334 )
      Yes, they're doing asteroid searches, too. But what, at this moment, appeals to the lowest common denominator scientifically uninformed American mind?
  • by youn ( 1516637 ) on Wednesday April 25, 2012 @04:28PM (#39799563) Homepage

    any unauthorized spaceships, doomsday stars and other prohibited devices should not be left in orbit without at least cloaking :p

    • Somehow I doubt the governments of the world would even have the tech to try to enforce the "unauthorized" part on "spaceships, doomsday stars and other prohibited devices" =)

  • by retroworks ( 652802 ) on Wednesday April 25, 2012 @04:36PM (#39799655) Homepage Journal
    And don't even ask about the amount of hard drive space to Photoshop the cosmos.
    • by mj1856 ( 589031 )

      "To the cloud!"

    • Quick, buy stock in HDD manufacturers! 6 million gigabytes (by which I assume they mean 5.7 petabytes) per year comes out to roughly 113 terabytes per week. I hope they get volume discounts on drives!

      Seriously, though, this is cool. I can't wait to see what sort of time-lapse videos they can make from this. Has anyone worked out what the pixels-per-arc-second resolution would be?

      • which comes out to roughly 30 (4 TB) hard drives a week, or maybe $6000. I don't think that's going to bankrupt a federal agency.

        Sure, you've got to double or triple that to pay for backups and replication, but let's be real - disk storage is cheap these days.

        • by MetricT ( 128876 ) on Wednesday April 25, 2012 @05:37PM (#39800291)

          I'm with the group at Vanderbilt developing the storage filesystem for LSST, and it has some interesting challenges.

          1. It requires redundancy at the server, rack, and site level. 2. Both data and metadata have to scale both in volume and in throughput (GB/sec or transactions/sec) separately of each other.
          3. It has to work on the WAN level (GPFS & Lustre don't scale beyond the LAN yet).
          4. It should optionally have HSM functionality so you can offload stuff to tape.
          5. The data must be maintained in perpetuity so researchers years/decades from now can use it.
          6. It must be portable across operating systems so Windows/Mac/Linux/etc users can all access the data.
          7. All of this should be completely transparent to the user.
          8. And it has to be done on the cheap (scientists definition of cheap, not CIO's definition).

          Yeah, it can be (and is) being done. We're already using our filesystem to store 2+PB of data for the CERN CMS-HI experiment on commodity hardware. But I can tell you it is a substantially harder problem than you think.

          • I assume you guys are familiar with the Lustre WAN work being done for the 2.x branch. For example:

            Not implying it does or will necessarily scale, in fact I'd be a bit surprised if you guys weren't following it but figured I'd toss it out there in case you weren't.

            Interesting project, I do same thing with radio telescope data but a much smaller scale (1/10th or so) without the added complexity of transparent ac

          • Hi there- I know that the scientists are loath to use any form of lossy compression on what could be priceless scientific data but I just wanted to ask if you are using any compression. I mean, images of this sort should be ideally suited to some forms of compression (a simplistic example would be RLE); after all, there is a lot of "space" (yuk yuk :).

            I used to work in digital cinema during the early trials and very prominent movie directors would often walk up to the projection screen, inches fom their fa

          • by Whip ( 4737 )

            Don't suppose you have a paper/website/whatever talking about your filesystem development work for this?

        • by jd2112 ( 1535857 )
          Unless the storage array has the letters E, M, and C along with the number 2 in which case it's more like $60,000.
        • newsflash... We ARE bankrupt.
      • Has anyone worked out what the pixels-per-arc-second resolution would be?

        OK, if my math is correct, assuming a single image encompasses the entire sky, this is 167 square arc-seconds per pixel, or about 13 linear arc-seconds per pixel. This would mean the moon would be 645 pixels across, Venus would be (currently) about 3 pixels across, and Jupiter at its closest would be about 4.

        • assuming a single image encompasses the entire sky

          That assumption is quite false: it takes an exposure every 20 seconds and takes days to form an all-sky survey. The pixel size is 0.2", so Jupiter at its closest would be 250 pixels wide, not 4.

        • The camera covers a little less than 9.7 square degrees, not the whole sky. (It's not a square image but an array of sensor chips, the array is missing corners to more closely follow a circular image shape.)

          The page [] lists the sampling resolution as "better than 0.2 arcseconds" (with 6 color bands per pixel 300nm-1200nm). That would make the moon 9000 pixels wide (assuming 0.5 degree width - it varies a little).

          • More - each pixel samples each of the six colors, (u-g-r-i-z-y, roughly 300-400-500-600-700-800-900-1000-1100nm) using filters. Each exposure is a bit less than 2.5s, for a total of 15s. The sequence is then repeated before the telescope is moved to the next patch of sky.

          • Well that's significantly cooler. I did read TFA, but didn't click through to the LSST site itself. Thanks for the details, and obviously you can't image the whole sky at once from the Earth. This would allow planetary surface details to be studied over time (although rotation means you won't see the same side in every image).

    • And once NASA sends it over to Target for printing, they'd probably downsize it anyhow.
  • by Reasonable Facsimile ( 2478544 ) on Wednesday April 25, 2012 @04:36PM (#39799659)
    ... just waiting to be dumbed-down with an instagram filter.
  • This is great news. Remember the scene in Star Wars where Obi-Wan uses that 3D star map, projecting from a crystal ball?
    With this, if the weekly image is public, we could actually create such real-time maps.

  • The first image would compress a factor of 2-5 depending on how good the S/N. Each image after that x100 using delta compression, unless there is something really funky going on in our neck of the woods

    • Astronomical data are background limited. The noise is as interesting as the signal, and many sources lie beneath the noise and are only visible through coadding. The gain and read-noise of LSST's detectors will be tuned similarly to other astronomical cameras because these parameters are governed by the experimental design.

      Lossless Rice compression should be around R of 2-2.5 ( with lossy compression of reduced data products falling between R of 3 to 5 depending on the

  • ... turn a KH-12 satellite around.

  • Comparing a hypothetical science instrument to an old grade of consumer device is poor hype. A better comparison is the 1.4 billion pixel camera on Pan Starrs that has been on the sky for two years now or the 340 megapixel CFHT-Megacam that has been on the sky for over nine years. If LSST is delayed much longer, a 3.4 billion pixel astronomy camera will sound like 8 megapixels in an SLR does today: obsolete.
  • Unless the members of congress can point it at the bedroom of the hot girl that lives across the street.
  • ...when is Samsung going to launch the SHDTV with the 3.2GP "lookback" feature?

  • World's Largest Digital Camera Project Passes Critical Milestone

    I've passed a tiny 1mm stone - a milestone must've been sheer agony.

Who goeth a-borrowing goeth a-sorrowing. -- Thomas Tusser