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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."

51 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. Re:N.W.A. by elrous0 · · Score: 3, Funny

      You are now about to witness the strength of scientific knowledge...

      --
      SJW: Someone who has run out of real oppression, and has to fake it.
    3. Re:N.W.A. by Conchobair · · Score: 2, Funny

      I hear they have top doctors working on an easy plan to use yellow fever to infect humans via wild wrens. Leaving us nothing but doggs and bones with little to eat but M&Ms wishing we were an exibit on deathrow in the aftermath.

    4. Re:N.W.A. by Chowderbags · · Score: 2, Funny

      And he's already committed crimes against humanity! Like "Are We There Yet?",and just when you thought it was bad, he made a sequel! This man must be stopped, perhaps by putting him someplace really cold, in fact I hear there's a continent if you go really far south that's just covered in ice...

  2. IceCube? by gstoddart · · Score: 3, Interesting

    What, the rapper?

    No, seriously. I think I remember reading about this earlier this year in Scientific American or something ... only it was on a big lake in Russia and they worked during the winter when everything is frozen. Kind of cool, bleeding edge stuff.

    I gather that the one in the Antarctic will be bigger, and give a view in a different direction than the Russian one.

    --
    Lost at C:>. Found at C.
    1. 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.

  3. 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 mcelrath · · Score: 3, Interesting

      Ice Cube operates by observing visible Cerenkov radiation from electrons and muons created when high-energy neutrinos hit an atom in the ice, as they traverse the ice. Of course, ice being transparent to visible light is important here, and lunar regolith is opaque to visible light.

      However it has been proposed to look for radio waves being emitted in a similar manner. Cerenkov radiation is caused by moving faster than the speed of light in the medium -- it's the "blue glow" if you look at the picture on that wikipedia link, and emits a broad spectrum of radiation, down into radio frequencies. Depending on the composition of the regolith, it may be transparent to radio waves. This can be done from the Earth by pointing your antenna at the moon, or from satellite(s) in orbit around the moon. You might be interested in the Goldstone project. So, at least with proposals I've heard about, getting people on the moon to make big holes is not an important component, but the surface of the moon may still be useful for similar experiments. You never know though, maybe tomorrow someone will post a new idea!

      --
      1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
    3. 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.
    4. 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.
    5. 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
    6. Re:Interesting... by kievit · · Score: 2, Informative

      I agree that the background reduction due to lack of atmosphere is very convenient, but as zero.kalvin points out, you still need a 'refracting medium', that is, a really large volume of transparent material such as water or ice (in which you can catch the Cherenkov light whenever a neutrino is kind enough to interact and produce fast charged particles). The large volume is not needed to suppress background, but to beat the very small cross section; in order to detect neutrinos you need them to interact with your detector, and the only way to achieve that is to make it as big as possible.

      There is ice on the Moon, but to harvest that and turn into a detector poses some interesting challenges. To use it in frozen form is hard, because you need it with a clarity and purity similar to the exceptionally clear deep Antarctic ice that IceCube uses and which is even clearer and purer than laboratory ice. To use it in liquid form requires keeping it heated, which is probably easier (you need a solar panel farm to power the heating system, but for the ice option you would also need those panels, to power the elaborate purification system + clear ice machinery). Either way: probably science fiction.

    7. Re:Interesting... by zero.kalvin · · Score: 3, Informative

      Actually yes, the near vacuum condition will help a lot on the angular resolution. But you will run into a lot of problems: The near vacuum conditions will mean that for the muon to create a Cherenkov light cone it would have to be hyper-relativistic. Since the muons energy is about 33% of that of the neutrino, most Energy fluxs are decreasing with energy(negative power laws), and with a lower stellar mass(of the moon). You will detect far less events in general, specially in the lower energy region. If you can place your detector in a refracting medium(let's say water), with a reasonably sized telescope (1km3), I will let you do the calculation on how much water we will need, with all the electronics problem that are associated with it.

  4. But... by jellomizer · · Score: 3, Funny

    We don't care about the Stars on the Southern hemisphere. Those are boring. The Northern Hemisphere stars are where its at.

    --
    If something is so important that you feel the need to post it on the internet... It probably isn't that important.
    1. 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.

    2. 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.

  5. Who cares? by Captain+Splendid · · Score: 4, Funny

    Call me when they find Megatron.

    --
    Linux, you magnificent bastard, I read the fucking manual!
    1. Re:Who cares? by CarpetShark · · Score: 3, Funny

      Or some sort of ancient chair that shoots missiles into space.

  6. 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 zero.kalvin · · Score: 2, Informative

      It's the equivalent of telescope with a view range of 4*PI. You are looking everywhere at the same time.

    2. 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.

    3. Re:Not a telescope by Monkeedude1212 · · Score: 2, Funny

      It is a telescope, just one that doesn't "see" photons

      Okay, I thinkI got it.

      and that you don't have to point at a target to see it.

      Now you're just screwing with me.

    4. Re:Not a telescope by IceCubeComm · · Score: 3, Informative

      An event reconstruction from the 79 string detector configuration https://blog.icecube.wisc.edu/?p=1355

    5. Re:Not a telescope by starfishsystems · · Score: 2, Interesting

      Agreed, at least provisionally. A telescope is an instrument which "sees" objects at a "distance". Whether the mechanism is optical or otherwise is not the point, it's how effectively the device can give us information about specific distant objects.

      This array is more like a scintillation counter. It measures local phenomena. Perhaps, opportunistically, it could be used to infer something about distant objects, but in that sense it's still no more a telescope than a light bulb is a power meter.

      --
      Parity: What to do when the weekend comes.
    6. Re:Not a telescope by Steve+Max · · Score: 2, Informative

      It's ability to trace the sky using a carrier that was never explored in this way (except to "see" what happens in the sun, and during a nearby supernova).

      Using optical telescopes, we can get an image of how the universe looks in visible photons. In an x-ray telescope, we get an image of the universe in x-ray photons. In a cosmic ray telescope, we get an image in charged particles. IceCube (plus its northern sister, KM3Net) should be able to get an image of the universe in neutrinos with energies over 1 TeV.

  7. Telescope? by amicusNYCL · · Score: 3, Interesting

    I'm not sure that a neutrino detector is any more of a telescope than the sensor that decides when it's time for the lights to come on at night.

    --
    "Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
    1. Re:Telescope? by Steve+Max · · Score: 2, Informative

      Why? It captures information from a flux of particles (not photons, but neutrinos in this case) emitted by astrophysical objects. It allows us to study properties of those objects (and of the detected particles as well). It doesn't have a resolution high enough to give us an "image" of most of those objects, but Hubble can't image most single stars too. IceCube won't give you a pretty picture for APOD, but it will do everything else we can do with an optical telescope, or a charged particle telescope such as Auger.

    2. 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."

    3. Re:Telescope? by radtea · · Score: 2, Interesting

      Why? It captures information from a flux of particles (not photons, but neutrinos in this case) emitted by astrophysical objects.

      Because when speaking to a broad audience it behooves scientists to avoid terminology that they know will be confusing and misleading to laypeople. Anything else is an abrogation of their responsibility to communicate science clearly and unambiguously to the public.

      Besides, no one in these fields ever calls anything like this an (unqualified) telescope. So the purpose of doing so for a general audience seems to me to be solely to mislead and confuse, and I'm not at all clear why anyone would want to do that.

      Curiously, the link you provide to Auger describes it as a "cosmic ray observatory", almost as if the people who created the site were scientists, aware of their responsibility to communicate clearly.

      --
      Blasphemy is a human right. Blasphemophobia kills.
    4. Re:Telescope? by mrops · · Score: 2, Insightful

      I think amplification is the wrong criteria to define a telescope, a better criteria would be "convergence" or "focusing" of whatever spectrum we are looking at. That is the only common theme I can see in a Telescope, they all converge large amount of spectrum to a focal point. This may not be in a physical sense and may be done inside of a computer via munging of captured data from various physical detectors.

      In that respect, I still come to the same conclusion, that this is not a telescope.

  8. Mythbusters-style by Anonymous Coward · · Score: 3, Funny

    Did anybody else imagine a huge lense made of ice like they made in Mythbusters to light a fire?

  9. Re:Aliens put it there by 0100010001010011 · · Score: 2, Funny

    Close, they're just digging for the other Stargate and the chair.

  10. In the distant future by AnAdventurer · · Score: 2, Insightful

    Anyone/anything will wonder what on earth [sic] this is.

    --
    6.8SPC TR of 550, l xwind at 6, drift rt at 26" drops 77". AT has 503 ft-lbs at 1403 fps. FT 0.86
    1. Re:In the distant future by Bigjeff5 · · Score: 2, Funny

      Well, it will be quite apparent that it is our ill-advised polar ice-cap melting apparatus, which was ultimately the cause of our downfall.

      --
      Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
  11. Re:World's largest, eh? by Anonymous Coward · · Score: 3, Informative

    One cubic kilometer is not 1000 cubic meters.

  12. Re:World's largest, eh? by John+Hasler · · Score: 3, Informative

    > This thing has a volume of about 1,000 cubic m.

    1 cubic km. That's 10E9 cubic m.

    --
    Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
  13. Re:World's largest, eh? by atrain728 · · Score: 2, Informative

    It probably doesn't count because it's smaller.

  14. so The chair is really still there? by Joe+The+Dragon · · Score: 3, Funny

    so The chair is really still there?

  15. IceCube telescope by elrous0 · · Score: 2, Funny

    Straight outta Antarctica?

    --
    SJW: Someone who has run out of real oppression, and has to fake it.
  16. 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.

    1. Re:Muons, not neutrinos by Deep+Penguin · · Score: 3, Informative

      Not all the neutrinos, just nearly all. The moon is large enough to catch a statistically discernible (to IceCube) amount of neutrinos, casting a "neutrino shadow" on the Earth.

  17. Largest "telescope"? by DiracFeynman · · Score: 2, Interesting

    I'm not so sure if this can be considered the largest. What about the VLA or LIGO?

  18. Re:PCI by John+Hasler · · Score: 3, Insightful

    > ...shouldn't they reconsider the PCI bus being phased out...

    It is just barely possible that they might consider vendors other than Intel. Hint: ISA industrial stuff is still available.

    --
    Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
  19. Re:It is a big problem by zero.kalvin · · Score: 3, Informative

    I did not say they have a big rate of failure. By detectors you mean OM, or optical modules. Optical modules are attached to each line. This problem can't be solved by compensating in the software. if you put your lines to close you will start having problems of the light produced by the muons not reaching other OMs and getting blocked very soon. Spacing is required as there is already few photons to work with. If an OM is out, it's over. if they have an electrical failure on one of the lines, it's over for that line. When it was on the sketch board, they took this in consideration, that's why it's big and with so many lines and OMs. But I repeat if it's out, it's out.

  20. Re:World's largest, eh? by ekgringo · · Score: 2, Funny

    You don't happen to work for NASA by any chance, do you?

  21. Ice Cube? by PPH · · Score: 2, Funny

    Personally, I welcome our hip hop astronomer overlords.

    --
    Have gnu, will travel.
  22. Re:World's largest, eh? by Bigjeff5 · · Score: 2, Informative

    The Hubble doesn't count because it's nowhere near the largest. It doesn't even make the top 50 list, more like around 55'ish. The Hubble gets great images because it is in space, and doesn't have to deal with atmosphere and light pollution. It can also catch wavelengths that are largely absorbed by the atmosphere, like infra-red and UV. That makes it extremely useful, however almost all of the ultra-long range research (~13 billion light years) is done with earth based telescopes and fancy corrective software to account for the affect of the atmosphere.

    The two largest telescopes are each about four times larger than the Hubble.

    --
    Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
  23. Wait, why are we speculating? by Chris+Burke · · Score: 3, Informative

    The IceCube website and U Wisc. says it's a telescope. So, case closed as far as I'm concerned.

    --

    The enemies of Democracy are
  24. Re:It is a big problem by IceCubeComm · · Score: 2, Informative

    Actually they call the individual detectors DOMs-Digital Optical Modules. Each string has 60 DOMs on it (plus 4 DOMs on the surface config IceTop) and altogether there will be 86 strings. Right now there are 79. Of course they calibrate, test, re-test before deployment, and troubleshoot when there are problems, but yeah if a DOM is out it's out.