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Space Science

Hubble Builds 3D Dark Matter Map 177

Posted by timothy
from the turn-left-go-fast dept.
astroengine writes "Dark matter can't be spotted directly because it doesn't interact with electromagnetic radiation (i.e. it doesn't emit any radiation and reflects no light). However, its gravitational influence on space-time can bend light from its otherwise straight path (a phenomenon known as 'lensing'). Using a sophisticated algorithm to scan a comprehensive Hubble Space Telescope survey of the cosmos, astronomers have plotted a map of 'weak lensing' events. Combining this with red shift measurements from ground-based observatories, they've produced a strikingly colorful 3D map of the structure of dark matter."
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Hubble Builds 3D Dark Matter Map

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  • by Dilligent (1616247) on Sunday March 28, 2010 @08:42PM (#31651978) Homepage
    ...but I fail to see the 3D that was promised by TFA.
    I agree it's a nice picture but there seems to be no explanation as to what these colours actually mean, let alone any kind of conclusion drawn from what I presume to be "pockets of dark matter".

    Anyone care to enlighten me?
    • by drizek (1481461)

      Every map needs to have a scale bar at the very least. We need something to tell us where this thing is and what all the colors mean. Also, there is nothing 3D about it.

    • by dakameleon (1126377) on Sunday March 28, 2010 @08:50PM (#31652030)

      From TFA, the closest hint we get to the 3D nature:

      By combining the Hubble observations of gravitational lenses with spectroscopic red shift observations from telescopes on Earth, the 3D location of clumps of mass (dark matter, galaxies, black holes etc.) can be found. In this case, the white, cyan, and green regions are closer to Earth than those indicated in orange and red.

      but yes, the rest is pretty awful... it's just a starfield without any context with blotches of colour randomly scattered over it.

      • Wait, I thought the whole story was about someone getting a bunch of grant money to make a starfield without any context with blotches of colour randomly scattered over it.

    • Re: (Score:2, Informative)

      by Anonymous Coward

      X = X
      Y = Y
      Z = RGB

      FTFA: "the white, cyan, and green regions are closer to Earth than those indicated in orange and red."

    • by Chris Burke (6130) on Sunday March 28, 2010 @09:42PM (#31652340) Homepage

      ...but I fail to see the 3D that was promised by TFA.

      Yeah sadly it's the data that's 3D, not the presentation. They located the dark matter in three dimensions, the 3rd being distance according to red shift which is how it's colored. I can see how it's hard to find the explanation, too, what with them breaking up the story every couple paragraphs with a giant bold link to something else. I thought those were different news items at first!

      Bad presentation in the article aside, this is pretty amazing work. What a phenomenal instrument we have in Hubble.

      The article on the the Hubble site [spacetelescope.org], while similarly lacking a good explanation for the image, actually talks about dark energy more than dark matter. Apparently this data also indicates a universe expanding outward from every point, corroborating that theory, along with some GR experimental validation as well. Not bad for a days work.

    • by carlzum (832868) on Sunday March 28, 2010 @10:52PM (#31652754)
      There are 3D dark matter maps [wikimedia.org] out there. This map provides some context for someone on Earth.

      In this case, the white, cyan, and green regions are closer to Earth than those indicated in orange and red.

      The image doesn't really help me visualize the concept, but it attracted me to the article. That's probably the intent of these kind of images, grab people's attention and explain the findings when they want to know what the hell they're looking at.

    • Re: (Score:2, Insightful)

      by dwreid (966865)
      You'll find much more complete information here. http://www.esa.int/esaSC/SEMZ6GSVYVE_index_0.html [esa.int] Unfortunately Discovery is the web site that turns science into an infomercial complete with annoying ads.
    • You need to wear these special glasses...
    • Re: (Score:3, Funny)

      by edumacator (910819)

      ...but I fail to see the 3D that was promised by TFA.

      You have to stand about 3 feet away, and let your eyes go fuzzy. It's a cute picture of a unicorn.

  • by actionbastard (1206160) on Sunday March 28, 2010 @08:44PM (#31651994)
    The pic looks like the Zetarians [memory-alpha.org].
  • FAKE (Score:2, Funny)

    by timmarhy (659436)
    looks photoshopped to me
    • by jo42 (227475)

      Troll? Looks like a badly done Photoshop to me as well.

    • by Spad (470073)

      Well, it is, technically. They didn't just save the pictures directly off Hubble and post them on the internet, you know.

  • by Jane Q. Public (1010737) on Sunday March 28, 2010 @09:10PM (#31652134)
    ...especially when you consider it's a picture of something that very possibly doesn't even exist.

    There isn't any "scale bar" because you are not looking at something at any fixed distance! You are looking at (theoretically) blobs of stuff at various distances.
    • by Abcd1234 (188840) on Sunday March 28, 2010 @09:44PM (#31652356) Homepage

      ...especially when you consider it's a picture of something that very possibly doesn't even exist.

      It exists. Educate [wikipedia.org] yourself [wikipedia.org].

      • by Anonymous Coward on Sunday March 28, 2010 @09:57PM (#31652422)

        Thanks. It's worth noting that the Bullet Cluster results you linked to are only the most recent development in dark matter's nearly 80 year history:

        1933 - Zwicky studies the Coma cluster of galaxies and is surprised to find that these galaxies are orbiting each other much faster than he predicted based on their visible mass. He proposes that each galaxy actually contains much more mass than is visible.

        1959 - Measurements of galactic rotational velocities conflict with expected velocities based on the amount of matter observed to be present. The dark matter concept proposed by Zwicky is found to solve this problem too.

        1970s - Big Bang nucleosynthesis has trouble reconciling observations of high deuterium density with the expansion rate of the universe. Non-baryonic dark matter solves this problem as well.

        At this point, dark matter was simply an hypothesis. MOdified Newtonian Dynamics (MOND [umd.edu]) was another hypothesis with equal weight. But then in 2006 measurements of the Bullet Cluster supported the dark matter hypothesis over the MOND hypothesis.

        Simultaneously, WMAP [wikipedia.org] (2001-present) measured the microwave background radiation and independently confirmed the existence of dark matter. It also revealed an even larger amount of "dark energy" which confirmed the 1998 discovery [arxiv.org] that the expansion of the universe is accelerating.

        • At this point, dark matter was simply an hypothesis. MOdified Newtonian Dynamics (MOND [umd.edu]) was another hypothesis with equal weight. But then in 2006 measurements of the Bullet Cluster supported the dark matter hypothesis over the MOND hypothesis.

          I don't think you could really say MOND had equal weight until 2006. I got my physics degree in the late 80's/early 90's and while MOND was often mentioned along with dark matter, it was usually as a footnote of other possiblities. Very few considered it a

        • However, just this last year it was found that prior surveys of background radiation had missed the mark widely. Further, there is strong new evidence contradicting the assumption that we are in a "typical" region of the universe, simultaneously calling into question whether expansion is actually accelerating.

          Gotta keep up with the news, man!
      • Educate yourself. It's still just a theory.

        • Re: (Score:2, Funny)

          by Anonymous Coward
          Exactly! That's the same reason I'm a creationist: evolution is also still just a theory. I'm also not fooled by their lies that the world is more than 6000 years old, because all those physicists have are silly theories to back up their ridiculous zillions of years nonsense (or whatever the age is this week!). I support you 100%. The high priests of this "godless science" religion need to be removed from the pedastal they're sitting on!
        • Re: (Score:2, Insightful)

          by Kentari (1265084)

          So are Relativity and Quantum Mechanics.

          You say "theory" as if it's a bad thing, while it's the highest you can hope to achieve in science.

        • So is gravity. Coincidently, they're using the theory of gravity to support the theory of dark matter.
      • by ShakaUVM (157947)

        >>It exists.

        What are it's properties then? All we've observed are anomalies in gravity and space-time. Positing some mysterious form of invisible matter isn't an explanation at all - all we still know is that there's these weird things going on with gravity and spacetime, and that our current theories are incomplete.

      • Maybe you should educate yourself.

        You present as evidence exactly the same sort of imaging techniques that were used to make the image in question? That's really lame.

        That's like trying to prove that a photograph of a ghost is real by producing more photographs of the ghost. Hint: it doesn't work.

        There are alternative theories, such as MoND, that might explain this (since it explains the apparent gravitational anomalies in spiral galaxies, it is possible that it could explain this kind of gravitati
        • I would like to add that, as some have mentioned above, there is recent evidence that appears to support the dark matter theory over the alternatives, but there is also evidence even more recently that the other evidence was in error. So... all I am saying is that this "debate" is not yet decided. Wait and see.
        • by Abcd1234 (188840)

          You present as evidence exactly the same sort of imaging techniques that were used to make the image in question? That's really lame.

          No it isn't. It's incontrovertible evidence. Or do you have proof that the methodology is faulty (despite the results agreeing with other sorts of data, such as WMAP)?

          There are alternative theories, such as MoND, that might explain this

          No, there aren't. Even MOND proponents have admitted that *some* form of weakly interacting matter is *required* to explain the galaxy colli

          • Nothing is incontrovertible. That's one of those words that, when you hear it, you should probably run away.

            If you had bothered to read my other comments, you might have found out something yourself.

            And yes, other than this, which does appear (without having researched it fully) to support the existence of dark matter, most of the evidence I have seen that was supposedly "evidence of dark matter" was pretty equally evidence of some of the alternative theories. Just how much do you know about the evide
            • by Abcd1234 (188840)

              If you had bothered to read my other comments, you might have found out something yourself.

              I've read those comments. None of them appear to provide any evidence to either invalidate these and related findings, or provide a mechanism by which MOND or other theories could be altered to fit current observations.

              Just how much do you know about the evidence I have seen anyway? You seem to believe you are an expert on the matter.

              Well, judging by your comments, you certainly are. So, please, explain to me how t

              • You still aren't getting the point, are you? Hmph. Well, I will try again: I was referring to evidence that I HAVE SEEN. Perhaps there is lots of other evidence. You seem to believe so. But that's beside the point. And yes, in fact I do know quite a bit about the evidence that I have seen.

                Your supposed expertise in physics aside, you seem to need reading and logic lessons.
                • by Abcd1234 (188840)

                  And yet, for all that you know about the evidence that you have seen, you still haven't explained how MOND or other alternatives to dark matter can explain the results that I've cited, results which are accepted by most of the physics community as supporting dark matter while ruling out MOND. I mean, it's not like you can just cherrypick the results to fit your theory. You gotta explain them all.

                  So please, if you have citations or other references which explain how MOND can be altered to fit the latest re

                  • My, you do go on, don't you?

                    If you read more of my statements, not just the one you have been obsessed with, you will see that I was not saying that MoND could explain this... simply that (I am repeating myself here) most of the evidence that I have seen does support alternate theories at least as well as dark matter. I have already stated (as you would know, if you had actually been reading) that it might not apply here.

                    All I have said here, given the whole of my statements, is that -- contrary to yo
          • Oops... I forgot a couple of things:

            No it isn't. It's incontrovertible evidence. Or do you have proof that the methodology is faulty (despite the results agreeing with other sorts of data, such as WMAP)?

            It is nothing of the sort. You may know a lot about current physics but you obviously know squat about logic and evidence. You offered the wikipedia link as evidence that OP's picture is correct... yet they used exactly the same techniques (having to do with gravitational lensing) to produce the pictures.

            • by Abcd1234 (188840)

              See the AC. He explains it very nicely, so I won't bother.

              Honestly, how stupid do you think physicists are? They came up with the idea of dark matter *specifically* to deal with galactic rotational curves. You really don't think they put a little thought into local effects? Please...

              This is just classic Slashdotter arrogance. You somehow think you've achieved a brilliant insight that people who've spent decades specializing in the field somehow failed to notice.

              • Sure, I can find out. And I will. But I asked you, and you couldn't or wouldn't answer.
              • By the way, I just wanted to mention, since you seem so adamant about this: I did not assert or even imply that I thought physicists would not have considered the issue. That would be stupid. I simply asked you a polite question.
  • by A3gis (708791)
    looks like a My Little Pony pegasus got up there and jizzed all over the lens...
  • by tpstigers (1075021) on Sunday March 28, 2010 @09:36PM (#31652298)
    ... the disturbance I felt in the Force earlier. I thought I just had gas.
  • by Tomfrh (719891) on Sunday March 28, 2010 @09:45PM (#31652368)

    So luminiferous and aethereal! Almost magical like!

    • by Abcd1234 (188840)

      So, are you trolling, or are you really not aware that the jury is in and that dark matter has been [wikipedia.org] confirmed [wikipedia.org] (and more importantly, that MOND without any kind of weakly interacting matter has been ruled out)?

  • Old news? (Score:3, Insightful)

    by dido (9125) <dido@@@imperium...ph> on Sunday March 28, 2010 @10:35PM (#31652684)

    I actually submitted a story [slashdot.org] on this exact same topic back in 2007. The only thing new they seem to have now is a nicer picture, the article seems much lighter than the original article [bbc.co.uk] I linked to three years ago. The new article doesn't seem to indicate any new science that has developed since then, not even links or mentions of any new publications updating the findings in 2007, or even mentions of the scientists who are behind this work...

  • Star Trek TOS (Score:3, Insightful)

    by rsborg (111459) on Monday March 29, 2010 @01:00AM (#31653442) Homepage
    Is it me, or did that pic give anyone else a TOS flashback where they meet some energy-based alien that fucks with the ship?
  • by Tanuki64 (989726) on Monday March 29, 2010 @03:03AM (#31654082)
    ...is totally normal matter, but invisible for us because it is located in another universe? I am not a physicist so my idea might be totally wacko, but ages ago I watched the BBC documentation 'The elegant universe'. One of the string theories explained there proposed that the reason gravity is so weak compared to other major forces is that the 'strings', which are responsible for gravity have the ability to migrate into parallel universes. Therefore we always feel only a fraction of the gravity mass 'produces'. <--- Please be lenient with my very unscientific wording. :-)

    So when I saw this documentation I always wondered, when 'our' gravity migrates into other universes, shouldn't also migrate gravity from other universes into ours? I wondered if this theory was true, how would a black hole in a parallel universe look like here?

    So maybe, if we had the ability to fly to those places where hubble located the 'dark matter', we would find nothing. The space is curved there for no apparent reason. It is actually because of normal matter in a parallel universe.
    • by khayman80 (824400)
      The only other person to respond to you was too harsh. Your idea is "out there" and probably wrong, but it's not obviously wrong. It's even an interesting thought experiment. The same thing occurred to me during my undergrad in 2004, and the story is here [dumbscientist.com]. Long story short: normal matter in parallel universes wouldn't explain the Bullet cluster observations mentioned elsewhere on this page.

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