Catch up on stories from the past week (and beyond) at the Slashdot story archive

 


Forgot your password?
Close
typodupeerror
×
Space Science

Antarctic Telescope Funded 28

Posted by chrisd from the remote-control-please dept.
An anonymous reader writes "SpaceflightNow reports that a multi-institutional team of scientists led by the University of Chicago will receive $16.6 million from the National Science Foundation over the next five years to build a telescope at the South Pole aimed at piercing one of the darkest secrets of the universe. The telescope will help scientists to reveal new details regarding a mysterious phenomenon called dark energy, which makes the expansion of the universe accelerate."
This discussion has been archived. No new comments can be posted.

Antarctic Telescope Funded More

Antarctic Telescope Funded

Comments Filter:

  • Learn to fucking spell!!! (Score:1, Funny)

    by Anonymous Coward
    antarCtic! Antarctic! MORONS. It's like having JeffK write all your columns! "Lunix Dosent' Cahrash!"
    • Give the poster a brake (sic).

      Seriously, though, do American dictionaries spell it "Nucular" yet? Good enough for president after president, good enough for the dictionary.

      :-)

  • I have a few concerns I wonder if you all share.

    First, How much is it going to cost to keep the people there alive and happy etc... Last time I checked it gets very very cold down there, and it takes a LOT of power and money to maintain equipment as well as habitable conditions.

    Secondly, Why don't they make more use of it then finding out if some "dark energy," which to me sounds too sci-fi to be true, exhists or not?

    Thirdly, will it be stationary like Ariceibo or will they be able to move and aim the telescope. The closest I could find to an answer is, "This will be the largest bolometric array yet built," and I am not quite the astronomer, so I would like to know. It seems like an aweful waste to have it fixed there where it would have a small area to search as opposed to the much greater area it could search if it was aimable.

    My fourth and final concern is lighting... I know that in the northern arctic circle they have a lot of daylght in summer (something like 18+ hours if I remember right.) Is it the same for Antarctica? And how will they overcome that if it is?

    • First of all: they're going to place it in an already working base, so they already have the facilities needed for people.

      The answer to the "dark energy" matter could be something like: they don't know whether it exists or not, so they're trying to find out. Yes, the name sounds quite sci-fi, but it's only a name.

      For the lighting: depending on the actual distance from the pole they may have days or months of 24 hours daylight, but they're also going to have days or months of 24 hours night, so in the end they get even. Anyway I don't know whether this is a kind of telescope that can work only during the night or not, so maybe this problem does not exists.

      Maybe they're just using it during the "winter", when they have long nights and I suppose that other kind of scientist have less work, leaving space for them during the "summer", thus solving both the people and the lighting problem.

    • To learn more about this work and to develop the background that would satisfy your curiosity, I suggest taking the time to do some research, e.g. by checking out the websites for the principles involved in this project. There's also some excellent cosmological primers available on the web that go over some of this stuff; see e.g. Ned Wright's cosmology tutorial (here [ucla.edu] and especially here [ucla.edu]) as well as Wayne Hu's Introduction to the Cosmic Microwave Background [uchicago.edu].

      To go through your concerns one by one:

      1. The U.S., in concert with other nations, already maintains an extensive set of scientific facilities [nsf.gov] in Antarctica, in the form of permanent bases at the South Pole and at McMurdo Sound and Palmer Station. These facilities are manned and operated year-round. Their purpose is to provide logistical support for the scores of short- and long-term scientific projects that take place in Antarctica, such as the one described in this article. In other words, the issue of logistical support for such a project in Antarctica really isn't an issue; an entire organizational/logistical apparatus has been running for many years to provide this capability for science as a whole, and they'll only be one of many projects each year that will take advantage of it.

      2. There is already a significant amount of observational evidence for the presence of what's referred to here as "dark energy." One hint of the presence of such an energy component to the Universe comes from trying to reconcile two observations: the first is that cosmic microwave background data indicates that the large-scale geometry of space is flat; the second is that the matter density of the universe (both in baryons, or normal matter, and in unknown dark matter, not to be confused with "dark energy"), measured via a broad variety of techniques, can only provide about 20% of the mass-energy density required to make the large-scale geometry be as flat as is observed. What's the other 80%? If it can't be matter of some sort, then what is it? When this is combined with recent observations that the expansion of the universe is accelerating -- something only possible if such a "dark energy" component to the mass-energy density of the universe is present -- one is forced to take this possibility seriously. (there's a lot more to be said about this issue, but only if someone cares)

      3. The telescope will not solely look at one spot on the sky.

      4. Lighting is not really an issue; this is not a visible light telescope, but rather a microwave telescope. There are significant noise issues that will have to be confronted in the data analysis, but not really from day vs. night problems.

      • significant noise issues
        Actually, that's the best reason I can see to put a radio telescope down there. Having all the array cold will decrease the thermal noise generated by the array itself. Even though it's an rf instrument, and nominally doesn't care about light, I'd expect it to do its best work in July.

        • >> significant noise issues
          > Actually, that's the best reason I can see to put a radio telescope down
          > there. Having all the array cold will decrease the thermal noise
          > generated by the array itself. Even though it's an rf instrument, and
          > nominally doesn't care about light, I'd expect it to do its best work in
          > July.

          You're absolutely right that reducing noise is the main reason for going to Antarctica, but there are still significant noise issues that have to be dealt with in the data analysis. Thermal noise from the array is not fought by going to Antarctica, though; that's fought by cooling the bolometers down to 4 Kelvin with liquid helium. These experiments are attempting to detect variations in the microwave background at the level of fractions of millikelvin; cooling down to the ambient temperature, even in Antarctica, would not come close to addressing their thermal noise issues.

          Depending on the frequencies used in their observations, atmospheric molecular lines are a source of noise (e.g. from water vapor); since Antarctica is basically the biggest desert in the world, water vapor and other such lines are less of an issue there. More significantly, though, and again depending on frequency, galactic synchrotron radiation and emission from interstellar dust provide the largest noise sources.

        • Having all the array cold will decrease the thermal noise generated by the array itself.

          Not to mention they can overclock all their processors, woo hoo!
        • I plainly didn't RTFP, or I'd have known that a bolometer is a heat detector. Those wavelengths are a bit too short to be called RF.
          /me hangs head

    • Remember, down there they don't have that pesky ozone layer to obscure their view! :)

      GMD

    • "This will be the largest bolometric array yet built,"

      Bolometric: (bo-lo-met-ric) (1) A Standard unit of Mass, based upon a Mark I Bolo (Manufactured by GM's BOLO Division). For instance, a Bolo Mark XXXIII weighs in at 32,000 tons (U.S.) or a much more reasonable 213 Bolos.

      Which then begs the question; Is this the standard unit of measure for Dark Energy also?

      (Sorry, I even left my desk before posting this, but I couldn't resist.)
  • so how exactly will this telescope pinpoint "dark matter" any more than any other telescope? I mean, you don't really even know what you are looking for. Is it just that there is more night time to use it in, or is this just the only way they could sell this project.
    "Well, everyone thinks stars and galaxies are old and boring... Oh wait! We're going to look for "dark matter"! And maybe we'll do a little side project in anti-gravity super ray guns too!

    • Re:so... (Score:2, Interesting)

      by Bootsy Collins ( 549938 )

      > so how exactly will this telescope pinpoint "dark matter"
      > any more than any other telescope? I mean, you don't really
      > even know what you are looking for. Is it just that there
      > is more night time to use it in, or is this just the only way
      > they could sell this project.

      Neither.

      First of all, as an aside, when trying to learn about dark matter, there are some telescopes which are more useful than others; it depends on what you're trying to do. For example, attempting to map the dark matter distribution using weak gravitational lensing requires a telescope with a very wide field-of-view as well as excellent "seeing". The Hubble Space Telescope fails the first of those two conditions, while the Canada-France-Hawaii Telescope on Mauna Kea has traditionally been an excellent telescope for such work.

      But second, and more importantly, your question is off-base. The purpose of this telescope is not to investigate dark matter, but rather what's (unfortunately, imho) being referred to these days as "dark energy." If you were to talk to an old astronomer or a specialist in general relativity, they'd refer to it as "a cosmological constant" instead; if you were to speak with a particle theorist, they'd call it "vacuum energy density." The point here is to try to learn something about the energy density of empty space. That's a bizarre notion, I know; but there are particle physics reasons why you might think that such a thing wouldn't be zero, and astronomical observations that argue that we've already seen that it isn't zero. But those observations have been hard to do; there's a fair number of them, from different approaches, and they're generally quite consistent with each other, but it's still possible that they're wrong. And with something as counterintuitive as this, one would like the evidence to be still much stronger than it currently is. The observations this microwave telescope will do should come at this question from yet another angle, and with a fairly high degree of precision. And we'll see.

  • Yeah, a telescope at the South Pole would also have the major advantage of being away from any major cities. I've read that some of the best ground based telescopes are in big trouble, because cities are quickly expanding too close to them, causing serious light polution for the astronomers.

    They should put a radio telescope there, too... just so we can make sure we check every inch of the sky with SETI@Home ;)

  • The background temperature of the universe is so cold-hundreds of degrees below zero-that even ice is hot by comparison.

    Wow! In other news, a journalist explains that the sun is so hot that it makes BURNING COALS seem cold! The journalist goes on to say that he is so smart that he makes that door-knob over there look completely stupid.
  • Oh, Langley devised the bolometer:
    It's really a kind of thermometer
    Which measures the heat
    From a polar bear's feet
    At a distance of half a kilometer

    - Unknown

Slashdot Top Deals

Enzymes are things invented by biologists that explain things which otherwise require harder thinking. -- Jerome Lettvin

Close