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Astronomers Make Important Dark Matter Discovery 223

Posted by Zonk
from the matter's-goth-sister dept.
saudadelinux writes "To quote a press release on NASA's site, astronomers using the Chandra X-ray Observatory have discovered 'how dark and normal matter have been forced apart in an extraordinarily energetic collision.' There will be a briefing at noon, August 21 ET, on this discovery, with streaming media provided by NASA, and some details of the research posted on Harvard's Chandra site just beforehand."
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Astronomers Make Important Dark Matter Discovery

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  • I don't know exactly why, but whenever I hear about dark matter, I'm reminded of Zippy The Pinhead.
    • I don't know exactly why, but whenever I hear about dark matter, I'm reminded of Zippy The Pinhead.


      The real question: Is NASA having fun yet?
    • Think that's bad? (Score:3, Informative)

      by jd (1658)
      In recent studies of deuterium in the galaxy, they're finding less than 1/25th of what they're expecting, and almost entirely in the wrong places. They therefore conclude that there must be MORE than what they expect, but in a place/form that is invisible.


      Will Hannibal Lector please stop eating the brains of astrophysicists.

      • Re:Think that's bad? (Score:3, Interesting)

        by wanerious (712877)
        IAAAstrophysicist, so perhaps a good chunk of my brain has been consumed already, but are you certain you mean *deuterium*? Is there a cite for this? I worked on galactic chemical evolution, and I'm a little out of touch with recent developments in the field, but this is news to me. Or maybe we're all really as dumb as you think we are.
        • Re:Think that's bad? (Score:2, Informative)

          by bla (96124)
          yes, sir. i am not the parent, nor am i an astrophysicist, but i just saw it this afternoon on cnn.com

          clicky [cnn.com]

          • Re:Think that's bad? (Score:4, Informative)

            by TrekkieGod (627867) on Tuesday August 15, 2006 @04:12PM (#15913070) Homepage Journal

            I'm not an astrophysist, nor was I involved in the conversation before now, but I did read your linked article :)

            Thanks for posting it, btw. I was taking what the parent said for granted, and it sounded pretty bad, but now it looks like it was a combination of bad reading comprehension and badly worded writing. The article you linked to at least, doesn't claim scientists are finding less deuterium than they expected and therefore expect more. Quite the contrary, they're finding a lot more than they expected, and thus are deciding that their theories need to be changed. I quote:

            scientists had assumed that at least a third of the primordial deuterium present in the Milky Way was destroyed over time as it cycled through the stars...but FUSE found deuterium exists in amounts less than 15 percent below what was there originally.

            So, they thought there were massive amounts of deuterium was "destroyed" and that not as much was left. Destroyed is a pretty bad way of describing it, but they allude to it in the article that what they mean by it is, "was transformed into heavier elements by stellar fusion." Instead, they're finding out that the amount of deuterium in the galaxy now is only about 15% less than what they thought was the original amount available. They also mention it being in unexpected places, or rather, not distributed evenly, which they find unusual according to current theories.

            Nothing to complain about here. Seems to me that the astrophysicists still have their brains intact, and realize their theory needs to be tweaked if it doesn't match the evidence.

        • Don't blame me, I merely read this stuff [cnn.com]. :)
      • Re:Think that's bad? (Score:5, Informative)

        by The Great Pretender (975978) on Tuesday August 15, 2006 @01:58PM (#15911602)
        There was a recent article in Discover [discover.com] that profiled a physist (Mordehai Milgrom) who had come up with modification on Newtons law to explain the planets orbits (forgive me, I'm a layman in this but it seems that dark matter started as a way to explain the weird plant orbits in extended galaxies - I encourage you all to correct me).

        "Mordehai Milgrom never wanted to be a heretic. Twenty-five years ago, while poking around for a meaty research problem, he found one that changed the course of his career--and that might yet transform our most fundamental understanding of the universe. His ideas, long relegated to the fringes of physics, where all but cranks fear to tread, have finally become too intriguing for his mainstream colleagues to ignore. Milgrom's heresy? He denies the existence of dark matter, the shadowy and thoroughly hypothetical stuff generally held to make up 80 percent or more of all matter in the universe. Even though dark matter has eluded all attempts at detection, most cosmologists are convinced it must be out there."

        So potentially there may not be any dark matter and the vast money being spent on it's pursuit is being wasted. For the record I don't believe in string theory either. I have to say that I would love to subscribe to the simplicity of Milgroms ideas, but it's just a gut check that fitting the theory to the data is better than creating a fudge factor - which dark matter ultimately seems to be.

      • JD, you need to provide a citation for that "Informative" comment of yours.

        I suspect you're mistakenly referring to this study of deuterium near the galactic core [space.com], which says that the D-H ratio they found is consistent with other researchers' measurements that imply large amounts of dark matter.
        • No, I'm referring to this story [cnn.com], which appears to be dated to yesterday - assuming the "monday" talked of was this week's monday. Your link is 6 years older - the date was 2000 - and looks like a completely different study.
      • They therefore conclude that there must be MORE [deuterium] than what they expect, but in a place/form that is invisible.

        Please, don't let it be in the form of deuterium ore [imdb.com].
  • by dreamchaser (49529) on Tuesday August 15, 2006 @12:28PM (#15910905) Homepage Journal
    How about waiting for the 21st and THEN posting a story. There is literally nothing of substance yet. Oh wait, this is Slashdot. We'll just have it posted again in two days, then on the 21st, then on the 25th, etc.
    • by Tackhead (54550) on Tuesday August 15, 2006 @12:35PM (#15910965)
      > There is literally nothing of substance yet.

      Not at all. It's got plenty of mass, it's just dark.

    • How is parent offtopic?
      There is no data, other than what is given in the summary.
      If there is no information, why would one want to post the same in /., which is essentially a news discussion/b site.

      The only discussion that can happen on this would be pure guessworks, and maybe some funny comments.

      Mods, mark parent insightful, not offtopic.
    • by Anonymous Coward
      Chances are very good that it's an update to the results published by the same authors in the Astrophysical Journal in 2004, but using newer and much improved data. Pre-prints of the earlier papers are on astro-ph at http://arxiv.org/abs/astro-ph/0309303 [arxiv.org] and http://arxiv.org/abs/astro-ph/0312273 [arxiv.org]. The papers from a few years ago combined observations of the gas in a merging cluster of galaxies with gravitational lensing data that indicates the distribution of the dark matter. As the two clusters in question
    • NOOooo...!!! (Score:5, Insightful)

      by The_REAL_DZA (731082) on Tuesday August 15, 2006 @01:17PM (#15911283)
      Someone's giving us ADVANCE NOTICE on Slashdot and you're COMPLAINING?!?!?!
       
      I can't count how many times I've read something on Slashdot about something cool that's already happened, just barely, and said "Once again, information I could have put to much better use YESTERDAY!!!
       
      Zonk, pay no attention to the criticism; I for one WELCOME some in-advance info (might even vote for it for "overlord"...)
    • "To quote a commenter on Slashdot's site, Slashdot "editors" using the Slash approval queue have discovered 'how people will get annoyed with their Slashbacks that cover previously covered material that were formally known as "Dupes".' There will be a briefing at 12:29 PM CT, on this discovery, with streaming comments provided by Slashcode, and some details of dreamchaser's comment posted on Slashdot's site just beforehand."
    • These folks have just been taking a few cues from Steve Jobs and Apple. They announce that they are going to announce something, then let folks speculate wildly about what exactly it will be. Instead of a product launch touting the latest features, it'll be a theory launch touting the latest features. Not too different, really.

      The coolest part is when you extend this comparison to include the Reality Distortion Field. The combination of that with dark matter and cosmology could yield some amazing res
  • Question. (Score:2, Interesting)

    by LiquidCoooled (634315)
    If you shine a torch at some dark matter what does it become?

    Isn't dark matter just all the none illuminated items in the universe?
    Rocks and stones and humans and plants and animals and silicon and paper and all these things are what I would consider dark matter, I might be wrong but someone could add some illumination on the subject I would be most grateful.
    • Re:Question. (Score:5, Informative)

      by dreamchaser (49529) on Tuesday August 15, 2006 @12:30PM (#15910929) Homepage Journal
      A small portion of it is rocks, dust, etc. Prevailing theories hold that much (most) of it is made up of non-baryonic matter which has yet to be observed.
      • by gr8_phk (621180)
        also seem to think that stars orbiting a galactic center are supposed to obey Keplers laws... The discrepancy between the observed galactic rotation curves and the "predicted" one are then attributed to "Dark Matter" rather than someones poor understanding of basic physics.

        The only dark matter is in these guys heads.

    • by Silver Sloth (770927) on Tuesday August 15, 2006 @12:35PM (#15910973)

      Humans, at least alive ones, are not at zero degrees K, and therefore radiate energy, not much, but some. We might be said to be dim matter.

      http://en.wikipedia.org/wiki/Dark_matter [wikipedia.org]This link will tell you more.

    • Re:Question. (Score:5, Informative)

      by SupremoMan (912191) on Tuesday August 15, 2006 @12:38PM (#15911004)
      Not at all sir. http://en.wikipedia.org/wiki/Dark_matter [wikipedia.org]This should enlighten you a bit.

      In cosmology, dark matter refers to matter particles, of unknown composition, that do not emit or reflect enough electromagnetic radiation (light) to be detected directly, but whose presence may be inferred from gravitational effects on visible matter such as stars and galaxies.

      It's a blanket term used for stuff in the universe we think is there but haven't seen because we can not detect it's presence.

      • It's a blanket term used for stuff in the universe we think is there but haven't seen because we can not detect it's presence.

        It is worth pointing out (as I do every time this topic comes up on /.) that there are multiple dark matter problems on different scales, and there may be multiple kinds of dark matter to explain them (or conversly, multiple defects in our understanding of the laws govering large-scale gravitational dynamics.)

        Galactic dark matter, which is used to explain the flat rotation curves of
    • 'Dark' is a code word for 'We don't know.'

      Seriously.
    • Dark matter is something that effects things gravitationally, but doesn't emit or reflect any radiation. We can tell it's there because the galaxies hold themselves together. In fact, for the galaxies to hold themselves together it has to be something like nine times as common as normal visible matter.

      So, if you shine a light on dark matter, nothing happens because the light passes right through it, possibly being defracted by the gravitational pull, but that's it.

      The two biggest theories about what dark
  • by Petskull (650178) on Tuesday August 15, 2006 @12:30PM (#15910925)
    Now dark and normal matter will be one big family again, obviously with court supervision.
  • Measure DM (Score:5, Funny)

    by MECC (8478) on Tuesday August 15, 2006 @12:36PM (#15910975)
    As long as NASA doesn't try to measure DM in metric units, everything should go just fine.

  • In Soviet Russia, dark matter discovers YOU!

    Although In Soviet Russia, the presentation would probably be posted before the story.
  • by 4solarisinfo (941037) on Tuesday August 15, 2006 @12:41PM (#15911020)
    Due to recent events at NASA, we'd appreciate everyone helping out by recording the stream of the event, and puttting it... well somewhere you can find it later.
  • by OakDragon (885217) on Tuesday August 15, 2006 @12:42PM (#15911033) Journal

    Cool! Now I can get started on my warp engine!

    Yours, Zephram Cochrane

  • by eebra82 (907996) on Tuesday August 15, 2006 @12:44PM (#15911050) Homepage
    So what's the matter, NASA?
  • by Billosaur (927319) * <wgrother@NosPAm.optonline.net> on Tuesday August 15, 2006 @12:56PM (#15911133) Journal

    We like to refer to it as "matter of color."

  • Shouldn't that be "NASA Announces *Announcement Of* Dark Matter Discovery"?
  • August 21 (Score:2, Funny)

    by rolyatknarf (973068) *
    And on monday August 21, 2006 at 12:00 PM CST WDAF Channel 4 Fox News in Kansas City will air an hour long program detailing the latest news, weather and sports for their local viewing area.

    Details as yet are unclear as to the specific content.
  • Most cold dark "matter" is dark energy, which in turn is dark information. The stuff that nemories [uncyclopedia.org] are made of.

    If this Chandra experiment is successful, we should hook it up to Google to search all the info [westnet.com] we don't know about what didn't happen.
  • 1) Turn off lights
    2) stub toe on matter I can not see
    3) patent dark matter and the process by which to make it
    4) ...
    5) profit


  • Will someone please think of the poor helpless penguins !?!
  • Dark Matter (Score:4, Funny)

    by Lost Penguin (636359) on Tuesday August 15, 2006 @01:57PM (#15911594) Homepage
    Isn't this what a light bulb absorbs till it's full, and then you must throw it away?
  • by riptalon (595997) on Tuesday August 15, 2006 @02:28PM (#15911877)

    I would assume this is the Bullet Cluster (1E 0657-56) combined X-ray and weak lensing results that Maxim reported [harvard.edu] at the Six Years of Science with Chandra Symposium [harvard.edu] last November. The interesting bit is that in this merging galaxy cluster the hot gas (~ 30%) has collided and been brought to a stop while the dark matter (~ 70%) haloes which are collisionless have passed through each other and are offset from the gas. By plotting the weak lensing image (which shows the total mass) over the X-ray image (which shows the baryons/gas) you can therefore see the existance of dark matter, since the mass is in a totally different place from the gas you can see in the X-ray. This isn't a fundamentally new result but it is a very nice visual demonstration of the existance of dark matter. Rotation curves of galaxies and the temperatures of galaxy clusters had proved it already but with this you don't need to do any maths you can just see it. Page 25 of this 6.5 MB pdf [harvard.edu] is the one you want for the image.

  • I love this place (Score:2, Insightful)

    by tyler23 (995544)
    Why? Thanks for asking! I'll tell you.

    Because, no matter how many people post pronouncements definitively proclaiming that they, as expert perl programmers or css jockeys or what-have-you, know *quite certainly* that the term "dark matter" is just meaningless mumbo-jumbo, demonstating their amazing mental superiority over the cretinous astrophysics community and its running-dog lackeys in the Mainstream Science Media, the emergent wisdom of the oft-maligned /. readership nonetheless mods the few informative
  • Is this an advertisement for Galactus pulling a tablecloth out from under dark matter dinnerwear on "The Universe Has Talent?"
  • by Kent Simon (760127) on Tuesday August 15, 2006 @08:13PM (#15915442) Homepage
    Actual NASA Photograph of their Dark Matter discovery can be found Here [imageshack.us]

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