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IceCube Telescope Takes Shape Below Antarctic Ice

Posted by timothy on from the hard-mile-to-walk dept.

PabloSandoval48 writes "The world's largest telescope, currently under construction more than a mile beneath the Antarctic ice, is on schedule to be completed next year, according to a researcher at the University of Wisconsin, the lead institution for a scientific project called IceCube."

15 of 165 comments (clear)

  1. N.W.A. by Anonymous Coward · · Score: 5, Funny

    This IceCube project is part of a secret plan by the New World Alliance to take over current infrastructure.

    1. Re:N.W.A. by Major+Downtime · · Score: 4, Insightful

      I agree. Evidence is hidden in plain sight:
      O'Shea Jackson (born June 15, 1969), better known by his stage name Ice Cube, is an American rapper, actor, screenwriter, film director, and producer.
      He began his career as a member of C.I.A and later joined the rap group N.W.A

      http://en.wikipedia.org/wiki/Ice_Cube

  2. Interesting... by TrisexualPuppy · · Score: 4, Interesting

    Would there, however, be any benefit to having such a project set up under lunar regolith/base rock if we could ever get back to the moon?

    1. Re:Interesting... by zero.kalvin · · Score: 5, Informative

      As someone working in this exact field I would say no. Where are you going to put it ? The idea of burying it deep in a refracting medium is to eliminate cosmic rays as background noise, and allowing the neutrino to produce a muon which will do a Cherenkov light in the detector. You need a deep refracting medium for this, beside we use the whole earth as a detector because of the low cross-section the neutrino have. So with a smaller stellar body(the moon) you will have less neutrinos interacting, and this less data to work with.

    2. Re:Interesting... by radtea · · Score: 4, Informative

      Would there, however, be any benefit to having such a project set up under lunar regolith/base rock if we could ever get back to the moon?

      Yes.

      The reason why: there are virtually no high-energy muons in lunar cosmic rays, and high-energy muons, one way or another, are the major cosmic-ray background in these experiments.

      The reason why there are virtually no high-energy muons in lunar cosmic rays is due to their primary mechanism of production: on Earth, cosmic-ray protons smack into atoms at the top of the atmosphere, producing high energy pions, which decay into muons etc... and because of the low density of the atmosphere, the decay time is much less than the stopping time, so the muons have most of the orignal energy of the primary cosmic ray available to them.

      On the Moon, which notably lacks an atmosphere, the primay cosmic rays smack into the lunar regolith and therefore the pions are created in a very dense medium, and lose most or all of their energy before decaying. The muons thus created are relatively low energy and stop within a few meters--as opposed to terrestrial cosmic ray muons which are still seen in experiments like the Sudbury Neutrino Observatory, 2 kilometres underground.

      As such, a relatively small, relatively shallow detector on the Moon could produce comparable performance to the best terrestrial detectors, at only a few orders of magnitude higher cost.

      It may be worth mentioning that no one working in the field ever calls a neutrino detector a "telescope", as in English that word when used without qualification virtually always means "optical telescope", so the usage in this article is misleading and confusing, to the point where if were done deliberately I would consider the person doing it to be either stupid or dishonest. I guess maybe the person who wrote the article or provided the information for it has English as a second language.

      --
      Blasphemy is a human right. Blasphemophobia kills.
    3. Re:Interesting... by Intron · · Score: 5, Funny

      I guess this is a bad time to mention the Giant Strobe Light Project that we're doing in the Antartic ice sheet.

      --
      Intron: the portion of DNA which expresses nothing useful.
    4. Re:Interesting... by Chris+Burke · · Score: 4, Insightful

      It may be worth mentioning that no one working in the field ever calls a neutrino detector a "telescope", as in English that word when used without qualification virtually always means "optical telescope", so the usage in this article is misleading and confusing, to the point where if were done deliberately I would consider the person doing it to be either stupid or dishonest. I guess maybe the person who wrote the article or provided the information for it has English as a second language.

      Sure, unqualified it implies optical, but on the other hand we have radio telescopes, infrared telescopes, x-ray telescopes, and gamma-ray telescopes. Why not the IceCube neutrino telescope? Surely, though, the lack of the word "neutrino" in the title and the summary was a gross omission.

      --

      The enemies of Democracy are
  3. Who cares? by Captain+Splendid · · Score: 4, Funny

    Call me when they find Megatron.

    --
    Linux, you magnificent bastard, I read the fucking manual!
  4. Not a telescope by wagnerrp · · Score: 4, Informative

    This is an observatory, but not a telescope. It's an omnidirectional particle detector, not pointed at some distant star.

    1. Re:Not a telescope by Steve+Max · · Score: 4, Insightful

      It can infer the direction a neutrino came from, so (given enough time) it can make "images". In fact, they've seen the moon already, as a deficit of neutrinos coming from the moon's direction. It is a telescope, just one that doesn't "see" photons and that you don't have to point at a target to see it.

  5. Re:IceCube? by zero.kalvin · · Score: 4, Informative

    You are taking about Baikal, it's a similar but on smaller scale. The Russians are hoping to join KM3NET in the future.

  6. Re:But... by Anonymous Coward · · Score: 5, Informative

    IceCube is a neutrino telescope which looks through the Earth to the Northern Hemisphere. The Earth basically acts as a filter removing potential background signals.

  7. Re:Telescope? by necro81 · · Score: 4, Insightful

    I wondered about this, too. I don't think that telescope is incorrect, exactly, but it would be better perhaps to call it an Observatory.

    The key feature of a telescope as I interpret the word is amplification of visual phenomena. It makes tiny things seem big. Perhaps the nitpickers would say that the main feature of a telescope is that it can resolve finer and finer details - I'd say that's the same thing. An ancillary of this is that it tends to gather a large amount of otherwise feeble light from some small field-of-view so that, when that field of view is zoomed in to occupy the whole of a sensor (a camera, the eye, etc.) there is still something there to see.

    This neutrino detector doesn't have any sort of magnification in that sense. It doesn't even work in the electromagnetic spectrum! It's purpose isn't to zoom in on a phenomenon, but to detect it and tell us where it came from. It doesn't zoom in. By that token I would say that it is an observatory, not a telescope. It does, however, have light amplification through the use of photomultipliers. And, by virtue of its size, can be thought of as having better resolving power and sensitivity than its predecessors. By measuring neutron flux intensity as a function of angular position, it should be able to produce a sky map much that those from more conventional (optical, radio, IR) telescopes. Does this make it a telescope? I don't know.

    For comparison, the Compton Gamma Ray Observatory faced a similar challenge: it didn't have an aperture or light gathering and focusing mirrors common to "telescopes" of other wavelengths. It is not possible to do that with any materials we're familiar with - gamma rays are absorbed or pass right through; there can be no reflectance or refraction. GRO was, much like this neutrino experiment, a target that waited for gamma rays to pass through. Once they did the instruments would figure out their energy and where in the sky their originated from. Notice that they called it an "observatory", not a "telescope."

  8. Muons, not neutrinos by mangu · · Score: 5, Informative

    they've seen the moon already, as a deficit of neutrinos coming from the moon's direction.

    There's a deficit of muons, not neutrinos, from the moon's direction. Neutrinos pass through the moon easily.

  9. Re:But... by Deep+Penguin · · Score: 4, Informative

    But that's what it sees - the sensors point at the Earth and the filter software discards muon events that track from the sky, keeping events that come from underneath since muons coming from the Northern Hemisphere decay long before they can reach the detector. Neutrinos survive passing through thousands of miles of rock, so if it comes from the middle of the Earth, it's a neutrino. If it comes from the sky, it could be a neutrino, but chances are, it's a muon.