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NASA WISE Telescope Starts Taking Pics

coondoggie writes "NASA said its Wide-field Infrared Survey Explorer spacecraft successfully popped the cover off its infrared telescope and began 'celestial treasure hunt' mission of sending back what will be millions of images of space. The WISE lens cap served as a safety system keeping the ultra-sensitive lens and telescope system safe until the spacecraft positioned itself correctly in orbit. The cap also served as the top to a 'bottle' that chille the instrument and detectors. This cryostat is a Thermos-like tank of solid hydrogen."

43 comments

  1. Will hopefully find lots of dark asteroids by wisebabo · · Score: 4, Insightful

    I understand that WISE is particularly well suited for finding asteroids (its an infra-red telescope so can pick up warm objects and its a survey scope). If this telescope finds an asteroid with our name on it with enough time to do something about it, it will make all the money spent on the space program by all the countries of the world seem like spare change.

    (I wonder if this is first post. If so, it'll be my first.).

    1. Re:Will hopefully find lots of dark asteroids by Jerry+Smith · · Score: 0, Offtopic

      I understand that WISE is particularly well suited for finding asteroids (its an infra-red telescope so can pick up warm objects and its a survey scope). If this telescope finds an asteroid with our name on it with enough time to do something about it, it will make all the money spent on the space program by all the countries of the world seem like spare change.

      (I wonder if this is first post. If so, it'll be my first.).

      First rule in First Post: don't talk about First Post. Secondly the fact that a projectile has been diagnosed as hurtling towards Earth might not be so god for humanity, people that just found out that they have only a few days left to live tend to do weird things. Like "ending" neighbourly quarrels, letting dark emotions go loose, you name it. It's not like the Earth could dodge a projectile Matrix-style.

      --
      All those moments will be lost in time, like tears in rain. Time to die.
    2. Re:Will hopefully find lots of dark asteroids by Thanshin · · Score: 4, Funny

      It's not like the Earth could dodge a projectile Matrix-style.

      That's why God gave us anti-ballistic missiles.

    3. Re:Will hopefully find lots of dark asteroids by Anonymous Coward · · Score: 0

      Who is God ? I'm not into US politics. defense ministry ?

    4. Re:Will hopefully find lots of dark asteroids by troll8901 · · Score: 2, Funny

      No, no, it's UK politics. "God" refers to the secret service (equivalent) protecting the Queen. As widely known from the anthem, "God Saves the Queen" ...

      (Looks up) Weird, the dark clouds have rolled in so suddenly - it was all clear skies just now.

    5. Re:Will hopefully find lots of dark asteroids by Anonymous Coward · · Score: 0

      This scope is only making one pass before the cryostat runs out. With only one image, how are we going to plot the course of any asteroids?

    6. Re:Will hopefully find lots of dark asteroids by Anonymous Coward · · Score: 0

      Who is God ? I'm not into US politics. defense ministry ?

      Nah, multi-dimensional beings with rocket launchers on their left arm.

    7. Re:Will hopefully find lots of dark asteroids by Anonymous Coward · · Score: 0

      Get a brain, moran.

    8. Re:Will hopefully find lots of dark asteroids by teko_teko · · Score: 1

      If all else fails, we can collect the world garbage into one big ball and launch it towards the asteroid.

      We should be safe unless that ball of garbage heads back towards earth someday...

    9. Re:Will hopefully find lots of dark asteroids by Anonymous Coward · · Score: 0

      If all else fails, we can collect the world garbage into one big ball and launch it towards the asteroid.

      We should be safe unless that ball of garbage heads back towards earth someday...

      ah futurama..... the good old days

    10. Re:Will hopefully find lots of dark asteroids by Anonymous Coward · · Score: 0

      Who is God ? I'm not into US politics. defense ministry ?

      Nah, multi-dimensional beings with rocket launchers on their left arm.

      Nope, I killed that guy in Doom 2. And he didn't much "save" anyone, as he would even fight to the death with his own guys.
       
      Must be someone else.

  2. Why... by symes · · Score: 1, Informative
    ...so cold?

    WISE’s infrared telescope and detectors are kept chilled inside a Thermos-like tank of solid hydrogen, called a cryostat

    and surely the hydrogen will now boil off?

    And here's the Berkely page and the NASA mission page for a more succinct intro.

    1. Re:Why... by DNS-and-BIND · · Score: 0, Troll

      Uh, guy? I'm not sure that they really need the hydrogen, being in a hard vacuum a couple degrees above absolute zero and all. Oh, and at least give the NASA guys credit for capitalizing Thermos as a proper noun and registered trademark. PS: the boiling point of hydrogen is 20 degrees K, interplanetary space is about 4 degrees K. PPS ProTip: If you're going to strut about starting your comments in the Subject: line and bashing NASA for being unscientific, please add more to the conversation than the top two Google results for "wise mission".

      --
      Shutting down free speech with violence isn't fighting fascism. It IS fascism!
    2. Re:Why... by Doctor+Device · · Score: 1

      and surely the hydrogen will now boil off?

      my suspicion would be that the hydrogen is expected to escape, and that the cryostat was to prevent damage to the instruments due to sudden major temperature changes. I could be completely wrong, though.

      --
      -It is by will alone I set my mind in motion.
    3. Re:Why... by Anonymous Coward · · Score: 1, Informative

      PS: the boiling point of hydrogen is 20 degrees K

      Just to be pedantic, but as the article talks about solid hydrogen, I believe the relevant value would be the melting point? (14K: http://en.wikipedia.org/wiki/Hydrogen)

    4. Re:Why... by Anonymous Coward · · Score: 1, Informative

      Uh, guy? I'm not sure that they really need the hydrogen, being in a hard vacuum a couple degrees above absolute zero and all.

      Actually, they do. Satellites heat up when they are exposed to sunlight and their internal equipment usually generates heat as well.

    5. Re:Why... by Hurricane78 · · Score: 3, Insightful

      Uuum, first of all: Why would you not be sure that they really need it? Do you think they sent it up there just for fun??

      From what I know, 4K is way too hot / above the wanted temperature. Which is closer to 0.5K (dunno the exact temperature, but it’s a quick search).

      --
      Any sufficiently advanced intelligence is indistinguishable from stupidity.
    6. Re:Why... by Anonymous Coward · · Score: 5, Informative

      Yes, they do need the hydrogen to keep things chilly. The vacuum is a nice insulator, but can't prevent all the heat from all that sunshine hitting the satellite (and other sources) heating things up- including those very, very sensitive detectors. Noise from heat is the enemy, which is why they've gone through so much trouble to keep the detectors cold and safe in a covered 'Thermos' until ready to serve.

      The hydrogen is a nice heat sink in addition to the natural vacuum flask provided by Space, and is allowed to slowly boil off, carrying away what heat that makes it through. It's also why there's a definite time limit on the main part of the mission and effective lifetime; once they hydrogen is gone, the detectors begin to heat up, heat noise ruining all that lovely sensitivity.

      I suspect that they'll continue to get some results after the liquid hydrogen is gone but, much like similar previous missions, the "warm" part of the mission will not achieve anywhere near the same results as the first "cold" portion.

    7. Re:Why... by Jeremy+Erwin · · Score: 4, Informative

      Space, being a vacuum, does not dissipate heat all that well.

      The operating temperatures will be 30–34K for the 3.3 & 4.7 m detectors, 7.8 ± 0.5K for the 12 & 23m detectors and 17K for the optical system, which are achieved using a two stage solid hydrogen cryostat providing a minimum mission lifetime of 7 months allowing for a single full coverage of the entire sky.

      Update on The Wide-Field Infrared Survey Explorer (WISE).

    8. Re:Why... by khallow · · Score: 4, Informative

      and surely the hydrogen will now boil off?

      Exactly what they want. As the hydrogen melts and boils off, it removes heat which keeps noise down and image quality up. When the hydrogen finally boils off, it'll greatly reduce the value of the telescope since the internal components will heat up. That's probably when they'll end the mission.

    9. Re:Why... by mforbes · · Score: 3, Informative

      TFA specifies that the hydrogen will run out about ten months into the mission (including a month for systems check-out).

      --

      Allegedly real newspaper headline from 1998:
      Man Struck by Lightning Faces Battery Charge

    10. Re:Why... by Anpheus · · Score: 1

      If this is like any other NASA devices, they'll say it'll last X years and it'll actually last 5X years due to them meeting higher constraints than were necessary and last-minute ingenuity.

    11. Re:Why... by Anonymous Coward · · Score: 1, Informative

      PS: the boiling point of hydrogen is 20 degrees K

      Just to be pedantic, but as the article talks about solid hydrogen, I believe the relevant value would be the melting point? (14K: http://en.wikipedia.org/wiki/Hydrogen)

      At what pressure?

    12. Re:Why... by DogAlmity · · Score: 1

      I'm not sure that they really need the hydrogen, being in a hard vacuum a couple degrees above absolute zero and all

      Wrong!

      the boiling point of hydrogen is 20 degrees K

      Irrelevant!

      interplanetary space is about 4 degrees K

      Wrong!.

      Wow, a lot of wrong was packed into just a few sentences.

    13. Re:Why... by Trapezium+Artist · · Score: 2, Informative

      Doubtful. One thing you can be pretty sure of is that a mission that uses cryogenic expendables won't last much longer than planned. The tanks are built to a certain size and filled to brimming; working out how long that'll last is fairly straightforward. You might get perhaps 50% longer than calculated if you're very lucky (more likely you'll get less), but no way will it last five times longer.

      As an example, the Spitzer Space Telescope was planned for 5 years before the cryogens ran out: it lasted roughly 6.3 years.

    14. Re:Why... by Anonymous Coward · · Score: 0

      Space, being a vacuum, does not dissipate heat all that well.

      Jesus Christ, it's disturbing to see false information like this modded to +5.

      Heat radiates fine in space via thermal radiation:
      http://en.wikipedia.org/wiki/Thermal_radiation

      Some space craft even need heaters to prevent them from getting too cold if they have Sun shields or are too far away from the sun. Did you know that thermal radiation is even strong enough to produce measurable torques on space crafts?

    15. Re:Why... by Jeremy+Erwin · · Score: 1

      Nope Putting a huge radiator on your spacecraft will only get you so far.

    16. Re:Why... by Anpheus · · Score: 1

      I may have employed a bit of hyperbole, but lacking a specific example, it was Spitzer and some of the Mars rovers that I was referring to.

    17. Re:Why... by 1+a+bee · · Score: 1

      Heat dissipates by two means: conduction and radiation. (Convection is a by-product of conduction.) It's that former category of heat dissipation that's missing in space.

    18. Re:Why... by Anonymous Coward · · Score: 0

      As an example, the Spitzer Space Telescope was planned for 5 years before the cryogens ran out: it lasted roughly 6.3 years.

      Yes, but it works both ways. The Spitzer did last longer, but last year the Swallows Ultraviolet Channeling Krypton Spectral-analyzer only lasted for 5 minutes before boiling off it's fluids.

    19. Re:Why... by Nutria · · Score: 1

      Heat dissipates by two means: conduction and radiation.

      You forget convection.

      --
      "I don't know, therefore Aliens" Wafflebox1
  3. Re:But can it detect by Nialin · · Score: 1, Funny

    If we live long enough, they'll rename it in 2620 to Urrectum.

  4. Re:Lemme guess by Jeremy+Erwin · · Score: 2, Informative

    Thermos like. Or, if you don't want to step on anyone's trademarks, a Vacuum Flask. You can even see a picture of WISE's cyrostat at Wikipedia

  5. hydrogen-lined *Thermos* bottle??? by Nutria · · Score: 2, Interesting

    in a covered 'Thermos' until ready to serve.

    Am I the only one to notice that a Thermos Bottle (aka Dewar flask) insulated with solid hydrogen isn't, by definition, a Thermos Bottle, since a Thermos Bottle requires a vacuum and solid hydrogen isn't?

    --
    "I don't know, therefore Aliens" Wafflebox1
  6. Is that what WISE stands for?? by callinyouin · · Score: 1

    Huh... I thought it stood for WISE Is Space Exploration. Picture Yoda saying this and it all makes sense.

  7. Moon Struck by PYRILAMPES · · Score: 1

    Too bad Nasa can't make a telescope powerful enough to see the lunar landing site... But seeing into distant galaxies is a good start.

  8. Unfortunately not enough by bradbury · · Score: 2, Interesting

    Kepler and Corot are the missions which have been launched and will be searching for exoplanets over the next few years. WISE and Herschel are the missions that have been launched, which are not targeted at exoplanets, but instead in the IR region. WISE tends to be focused as a total sky survey mission in the near-IR while Herschel is focused more on the mid-far IR at more specific targets.

    Combined they potentially give use the ability to begin the search for Matrioshka Brains. IMO, one of the primary problems with astronomy and astrophysics is that the physicists (and most physics based research activities) start with the assumption that the "Universe is dead". But what if thats not true? What if it is in fact quite "alive"? This makes things horribly more complex for the physicists and astronomers because "life", esp. advanced intelligent life, can stretch the boundaries of what is determined by the laws of physics. Even more difficult -- for a complete "Theory of Everything" it probably means the physicists and astronomers are going to have to enter into serious discussions with the biologists and sociologists (to determine the characteristics that advanced civilizations might possess.

    The Kepler and Corot missions, because they are focused on stellar photometry (brightness) can detect transients of other objects in front of stars. So they may be able to provide some limits on the abundance of various "dark objects" orbiting between our solar system and those stars (the planet searches are obviously looking for repeats, but the data, once public could be scanned for transient occultations (i.e. one time apparent occultations which indicate something between us and the star, be it a nearby asteroid or a more distant Matrioshka Brain). Freeman Dyson has suggested that the study of stellar occultations would be useful (presumably recognizing that not every stellar occultation indicates a planet around the star -- some might represent intervening objects transiting across the field of view. Know the size of the object being viewed, and one can set limits on sizes/distances of what is being viewed). (And Jupiter Brains or Matrioshka Brains clearly fall outside of the realm of classical (read acceptable to the "realm of comfortability" of most astrophysicists). [I have been to several conferences of gravitational microlensing astronomers -- this statement is made on the basis of direct experience -- they think in terms of hard data and they will only reluctantly acknowledge ideas which conflict with those in which they have been trained).

    Now the WISE and Herschel missions are more interesting from the perspective that they begin to allow us to ask the fundamental question of "What is the rate at which Stars go dark?", i.e. what is the rate at which civilizations migrate from a pre-Kardashev type I level civilization (where we are now) to a Kardashev type II level civilzation (which does not require but is significantly enabled by the development of mature molecular nanotechnology [in the robust Drexler/Merkle/Freitas framework]. So the possible development rate could be measured in anything from months (which is feasible within our solar system, to decades, to centuries (solar system development has varying degrees of "difficulty")). And one measures that rate at that which a solar system goes "dark", with a slow conversion of visible light radiation (an undeveloped star) into an IR star (that being intelligently harvested) (i.e. the star effectively goes "dark"). We are just posed on this transition point ourselves, so it is not unworthy of study or discussion. Perhaps most importantly, the currently launched missions enable the setting of limits on the abundance of Advanced Extraterrestrial Civilizations. And it is useful to

    1. Re:Unfortunately not enough by Anonymous Coward · · Score: 0

      tl:dr

  9. Amy Mainzer by Anonymous Coward · · Score: 0

    FYI, the WISE project is the pet of a legitimate geek goddess, Amy Mainzer. Some of you may have seen her on the History Channel.

    http://science.jpl.nasa.gov/people/Mainzer/