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Space Science

Galaxies Floating on a Dark Matter Stream 173

Darkman, Walkin Dude writes "A team in Switzerland has discovered that most of the small satellite galaxies around the Milky Way's near-twin, Andromeda, are lined up in a single plane that slices through Andromeda's spiral disc. Using images from the Hubble space telescope, soon to be decommissioned, the researchers found that 9 of the 14 of Andromeda's satellites lay on a relatively narrow plane bisecting Andromeda. From the article: 'The team believes the plane could have formed in several ways. In one scenario, the galaxies may have fallen towards Andromeda along an invisible filament of dark matter. Computer simulations show these filaments can form a cosmic web along which galaxies flow.'"
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Galaxies Floating on a Dark Matter Stream

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  • by eldavojohn ( 898314 ) * <eldavojohn@@@gmail...com> on Sunday January 15, 2006 @06:42PM (#14477855) Journal
    These are called Sombrero Galaxies [nasa.gov]. I believe M 104 [wikipedia.org] is the most famous since it was first noticed on May 11th, 1781.

    Does dark matter hold our universe together in a web? Perhaps, though this would mean that there is no such thing as truly empty space as a small amount of dark matter would have to exist. Perhaps what lays beneath the edges of our universe is nothing in the sense of it being devoid of dark matter?

    Check this out:
    Consider this fact: In the air we breathe, each cubic centimeter contains roughly 5 X 1019 atoms. In contrast, the intergalactic medium has a density of only 10-6 particles per cubic centimeter--each atom inhabits a private box a meter on each side. This would seem to suggest that there is not much matter in the intergalactic medium. But, given the enormous volume between the galaxies, it quickly adds up: The combined atomic mass of intergalactic gas exceeds the combined atomic mass of all the stars and galaxies in the universe--possibly by as much as 50 percent! There is indeed something in empty space
    From this article [americanscientist.org].

    While this article only mentions computer simulations, many scientific groups have gone along further researching, convinced that the cosmic web does exist [ociw.edu]. Some people [roe.ac.uk] have based most of their work on dark matter and the cosmic web though I believe it is still speculation [wikipedia.org] and has yet to be accepted by the science community as a whole. I've read some crazy stuff about dark matter, like how it might be the "gravity particle" that is attracted to matter uniformly and causes the gravitational pull between objects. And even crazier books suggesting that the only way we'll ever be able to communicate between parallel existences is by lowering and raising these gravity particles.

    Now, the slashdot community seems to be fairly educated and extremely opinionated so how about it--does dark matter exist? If so, since it is very difficult to detect, what are its defining properties?
    • by gEvil (beta) ( 945888 ) on Sunday January 15, 2006 @06:46PM (#14477878)
      Does dark matter hold our universe together in a web?

      I think it's more like invisible strands of spaghetti.
    • by Anonymous Coward
      How the fuck did you write such a thorough and cogent response as a FIRST POST nonetheless??!?!?!
    • If so, since it is very difficult to detect, what are its defining properties?

      It's cold,
      and err.. dark,
      and umm...
      oh yeah, it's matter
    • You cant really tell apart if you are reading science and pseudoscience (talking about the "parallel existence" stuff). And i seriously dont know why you think that the graviton is dark matter... or are you mixing this part up and mean the higgs boson?

      About this "web of dark matter": The WMAP data of the galactic background STRONGLY supports this hypothesis. The anisoropy is just too large, and too soon to be explained by non-external (i.e. non-photon interacting) gravitational influences.
    • This subject is soo obscure to me :P

      haha joke apart...

      this brings in me again the idea that the universe is may be some kind of uber-big life-form... lying in a multi-dimensional world... interacting through gravity.... i dont know...that idea suddenly came to my head...
    • "Computer simulations show..." is another way of saying "computer programmers imagine...", but presumably something in reality OTHER THAN coincidence posits this weblike dark stuff, right? Presumably one tests one hypotheses with a few more data points than those one started with? In the meanwhile, I propose we give this Dark Matter a new name, such as "Ether", "Phlogiston" or "Element X", at least until we can kleinbottle it and tie it up with strings.
    • By the "crazy gravity particle" do you mean the Higgs Boson or the gravitron? One is part of the Standard Model.
    • by Ckwop ( 707653 ) * <Simon.Johnson@gmail.com> on Sunday January 15, 2006 @07:43PM (#14478172) Homepage

      Now, the slashdot community seems to be fairly educated and extremely opinionated so how about it--does dark matter exist? If so, since it is very difficult to detect, what are its defining properties?

      If this [cerncourier.com] is correct, then the Dark Matter riddle has been solved. Basically, it was due to the fact that scientists thought they could safely use the Newtonian limit to General Relativity with galaxies. They were wrong and Dark Matter is a result of this error.

      This was reported [slashdot.org] on Slashdot not to many moons ago.

      Simon

      • one paper was written, and it has (as far as i know) been proven to be correct. saying that dark matter has been disproved because of just one paper is foolish. scientific understanding is based on replication of results. you should wait until they are replicated. this is the problem with the media they lean on institutions to releases there informations before they are ready.
        • by drudd ( 43032 ) on Sunday January 15, 2006 @10:03PM (#14478819)
          The current consensus is that the paper is fundamentally flawed, and that when done correctly non-linearities from GR cannot explain the flat rotation curves of spiral galaxies (not to mention the vast amounts of other evidence for dark matter including hot gas in galaxy clusters, fluctuations in the cosmic microwave background, strong lensing arcs in clusters, weak gravitational lensing by galaxies, the distribution of galaxies on large scales, etc).

          Unfortunately, the general public only hears about the initial press release, not the work of many other scientists in debunking those results.

          Doug
      • by Stalyn ( 662 ) on Sunday January 15, 2006 @09:51PM (#14478759) Homepage Journal
        Might want to do some actual research [arxiv.org] on the subject. From that list there are no articles in support of the Cooperstock-Tieu model other than a response by the orginal authors. The theoretical arguments and evidence against the model are quite convincing.

        Dark matter is just the best model we have right now. It also amazes me how much Slashdot is against the dark matter model. Why is that?
        • Well, dark matter is similar to claiming that you have an invisible red dragon in your basement and that this invisible red dragon is the master of the universe. If it cannot be proven to exist, then it is on the same level as religion and intelligent design and incompatible with science. Pure conjecture, fantasy, nonsense, bull...
          • Actually dark matter can be proved or disproved... it just hasn't been yet. Also there is indirect evidence for dark matter. Do you believe in String Theory? Dark matter has more evidence and theoretical weight than string theory.
        • "It also amazes me how much Slashdot is against the dark matter model. Why is that?"

          Selection bias.

          Those with an axe to grind shout the loudest and post the most often. The silent majority just keep scrolling.
        • Just because something is the "best model we have now" doesn't suggest that it's right or even on the right path. Centuries ago, the best model to answer many scientific questions were theological. They were the only models. The lack of better answers didn't stop them from being bad answers. And although you are correct that the Cooperstock-Tieu model does have detractors they note problems with the model which would require revision rather than constituting debunking.

          Vogt and Letelier even note:

          Althoug

        • Dark matter is just the best model we have right now. It also amazes me how much Slashdot is against the dark matter model. Why is that?

          No model is better than a bad model.

        • Dark matter is just the best model we have right now. It also amazes me how much Slashdot is against the dark matter model. Why is that?

          Lack of faith.

          Dark matter is an unproven hypothesis (actually, multiple unproven hypotheses) that can be fine-tuned to account for any particular set of observations. However, there is as yet (to my knowledge) no generally accepted, closed set of parameters for dark matter models that will consistently explain all observed phenomena.

          The "Dark Matter Problem" is at least tw
        • Though I'm rather late to the discussion, and I doubt no one will read this:

          It's not just the slashdot community. Dark Matter is an idea that was come up with to explain events that our math theories, based on observations, could not explain. Large non spherical bodies of mass were needed to explain certain problems with red shift, universe expansion rate not being constant, and other oddities. It's a lot like Aether. Aether was someone's idea to come up with how light travels in wave form. Since our

    • Empty Space (Score:3, Interesting)

      by jd ( 1658 )
      There is no such thing as empty space, as that would violate all kinds of laws of physics. (It would exist in a constant state of entropy, there would be zero quantum uncertainty, it would allow for the possibility of an absolute frame of reference, etc.)

      In general, the popular belief is that ALL of space is filled with "quantum foam", which contains a mass of virtual particles whose sum (over any statistically significant volume) will be zero. These virtual particles are not "dark matter", precisely for th

  • ID (Score:5, Funny)

    by SoulMaster ( 717007 ) * on Sunday January 15, 2006 @06:57PM (#14477942)
    In another scenario, the Intelligent Designer put them on that specific plane just to see how long it took before somebody noticed and claimed that it must be Dark Matter.
    • Re:ID (Score:3, Funny)

      by NanoGator ( 522640 )
      "In another scenario, the Intelligent Designer put them on that specific plane just to see how long it took before somebody noticed and claimed that it must be Dark Matter."

      Yeah yeah, we get it, fanatics suck. Let's not be fanatical about bringing up the fanaticism of the fanatics, k?
    • ...or on the other hand it might be a total coincedence that in this huge (or infinite?) universe there is a small number of galactical objects that accidentally appear to be in a line?

      We can't be certain just now, but I think Occam would agree with me.

    • Potestatem obscuri lateris nescis.

      - You don't know the power of the dark side.
  • So does this mean that the photino birds are winning or the Xeelee?
  • Eric Lerner (Score:5, Interesting)

    by Bloater ( 12932 ) on Sunday January 15, 2006 @07:19PM (#14478052) Homepage Journal
    The team believes the plane could have formed in several ways. In one scenario, the galaxies may have fallen towards Andromeda along an invisible filament of dark matter. Computer simulations show these filaments can form a cosmic web along which galaxies flow.'


    Eric Lerner [wikipedia.org] is looking less and less like a crank with every new cosmological experiment, I think this is exactly what his plasma filament theory [bigbangneverhappened.org] of the intergalactic medium has been predicting.
    • ...here [thunderbolts.info]. With some uberkewl photos to back up what they're saying.
    • I don't see why you get that impression. Among other things, he apparently advocates an infinitely old universe. But we haven't discovered objects older than roughly the claimed age of the universe, ie, on the order of 13 billion years. Where are the trillion year old objects or the quadrillion year old objects?
      • > I don't see why you get that impression. Among other things, he apparently advocates an infinitely old universe. But we haven't discovered objects older than roughly the claimed age of the universe, ie, on the order of 13 billion years.

        How do you know how old they are? From the redshift. The big bang predicts the bodies are flying away from us, and the rate they are moving (degree of redshift) indicates the distance they have accrued from the location of the event. Finally, from that distance you calcu
        • I was thinking quadrillion year old objects in our own neighborhood. But there are other indications. For example, the relative scarcity of elements past helium in the universe. We can determine with reasonable accuracy the age of stars, nearby and distant. One interesting point is that there is a lot of evidence of creation of heavy elements within the last 10 billion years. We have a class of old (say 10-13 billion year old)stars that are metal-poor, and a bunch of newer stars (like the Sun) that have muc
          • > We have a class of old (say 10-13 billion year old)stars that are metal-poor, and a bunch of newer stars (like the Sun) that have much higher concentrations of heavy elements.

            How do you determine their ages? And how is our sun supposed to get so much in the way of heavy elements from the old stars, when the old stars don't have much to provide? Also, a star with little in the way of heavy elements is likely to eject more matter than a heavy star with lots of iron, which is likely to collapse and start
            • How do you determine their ages?

              We have models of stellar evolution that do a good job of predicting the observed characteristics of stars. For example, the Sun's mass, rate of fusion, and rough age is pretty well known. We have models that indicate the Sun is about halfway through it's life as normal star. These models fit with observed frequency of stars, isotope distribution, brightness, and other observable components of the population of stars near us.

              Heavy stars generate most of the heavier eleme

  • by Noxx ( 74567 ) on Sunday January 15, 2006 @07:38PM (#14478155)
    In one scenario, the galaxies may have fallen towards Andromeda along an invisible filament of dark matter.

    In another scenario, the Flying Spaghetti Monster [venganza.org] might have used His Noodly Appendage to intelligently design it that way. Scientists speculate the arrangement makes it easier for Him to make a bank shot on the 9-ball galaxy.

  • Right. (Score:5, Funny)

    by balloot ( 943499 ) on Sunday January 15, 2006 @07:42PM (#14478170)
    Am I the only one who thinks this headline sounds like something some scientist completely pulled out of his ass? "Yeah...so you know dark matter? All the planets are, like, floating on it. And I am TOTALLY stoned...."
    • by suso ( 153703 ) *
      Wait, I've seen this episode of Star Trek. We have to get two dimensional!
    • Oh yes, exactly! And did you know that if you accelerate and I do the same in different direction, and a tree falls somewhere between us we'll never agree at which time it happened? It's totally out there...

      I'm not saying the Styx thing is true, only that eventually, time will tell. And if it doesn't prove to be true now, it's maybe because current instruments are too crude to prove it yet. As someone one said, reality is SO much more weirder than fantasy.

  • a name for it (Score:5, Interesting)

    by heatdeath ( 217147 ) on Sunday January 15, 2006 @07:56PM (#14478238)
    If they eventually find more evidence for these "dark matter streams", and start naming them, I think "the styx" would be a completely awesome name for such a stream.
  • Old Lady (Score:5, Funny)

    by nacturation ( 646836 ) <nacturation@gmCHEETAHail.com minus cat> on Sunday January 15, 2006 @10:00PM (#14478809) Journal
    Galaxies Floating on a Dark Matter Stream

    So, the old lady was right... it's turtles all the way down.
     
  • by fygment ( 444210 ) on Sunday January 15, 2006 @10:41PM (#14478986)
    So we have two theories:

    a) dark matter filaments (modeled on a computer no less). Matter we cannot see; who's existence is contentious, etc.

    b) the remnants of a cannibalized galaxy. Solid evidence of this principle abundantly available.

    Why leap to the more complicated and, arguably esoteric, explanation?
  • by Snafoo ( 38566 ) on Sunday January 15, 2006 @10:43PM (#14478992) Homepage
    AP - Scientists at the prestigious CERN institute in Switzerland announced late Friday that the so-called 'dark matter', which makes up 90% of the universe, is actually bullshit.
    "These findings come as a surprise," stated Dr. Weissmann, lead scientist at the institute. "Before today, we thought dark matter might be, say, an agglomeration of exotic subatomic particles, like muons or 'strange' quarks, signifying a problem with the equations governing space-time. Instead, all that turns out to be bullshit."
    Other hypotheses included Cheez-puffs and intelligent end-users. But the conclusive evidence for the new Bullshit Theory of Matter came from the Hubble space telescope, which since 1995 has been sending back data that, according to scientists, is "complete and utter bull."
    "Over and over we ran through the equations, and each time we came up with the same answer: This is crap," affirmed Weismann. "It's satisfying, in a way, to be able to say that about your life's work."

    -C.
    • Working in conjunction with the Sloan Digital Sky Survey at Fermilab, they were able to determine most of the universe's galactic sheet structures were aligning themselves with a majob B.S. /dark matter production source, centered in G.W. Bush's voice box.
  • by alex_guy_CA ( 748887 ) <`alex' `at' `schoenfeldt.com'> on Monday January 16, 2006 @12:23AM (#14479454) Homepage
    I've heard Dr. Michio Kaku theorize that dark matter is the gravitational effect of the matter of other universes that are close to ours. I found that to be an intriguing thought, bringing two pretty wild ideas, dark matter and multiple universes, together in a coherent and even intuitive way.

    ahref=http://www.mkaku.org/rel=url2html-18972 [slashdot.org]http: //www.mkaku.org/>

    • It's also possible that the massive black holes in the center of these galaxies are culpable and that the stringing together of galaxies has nothing to do with any kind of dark matter stuffs, but a hole-to-hole effect, kinda like the soup cans with a string but on a different scale (analogies and similies can be fun!)

      A lot of mysteries are going to vanish once we get a handle on what is really happening with these black holes: The event horizon is where our current theories seem to, well, run into a black h
  • I, for one, bow before our dark matter photino bird overlords from Andromeda...

    Unless if the Xeelee get them first.
    • I, for one, bow before our dark matter photino bird overlords from Andromeda...

      Bow or don't bow, it's all much the same to them. These guys are worse than Cthulhu, they don't even want to eat you... just the sun.

    • > I, for one, bow before our dark matter photino bird overlords from Andromeda...

      How do you know you're not bowing behind them or in the wrong direction entirely, given that you can't see them?
  • Wow! So it really does exist...I just thought it was movie...

    2 cents,

    Queen B
  • This is old news. Halton Arp (a famous and controversial astronomer) found this in the 1970s. But this discovery didn't fit with the galaxy models of the time (dark matter hadn't been introduced yet), so the finding was ignored.
  • Wow, I got chills reading this. I just finished reading Ring [amazon.com] by Stephen Baxter, which is amazingly relevant to this news. I won't spoil the plot, but among other things it is about dark matter being used to shape and influence the visible universe on a huge scale. Of course a liberal amount of artistic licence is applied, and Baxter's writing ability is less stellar than the plot, but the plot is on such an enormous, awe-inspiring scale that that hardly matters.

    It was the first story from his "Xeelee Sequ

  • ...so above and beyond I imagine"
    Maynard James Keenan

    Could dark matter be the ley lines [wikipedia.org] of the universe??
  • Let's say I give you 14 random points near Andromeda. What are the odds that you could pick 9 of them and find some "plane" that contains them all? I guess it depends on how thick the "plane" is (which the article doesn't say), but I bet it's not that hard.

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