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Galactic Pancake Mystery Solved

mOoZik writes "According to the BBC, Astronomers have figured out why a series of small galaxies surrounding the Milky Way are distributed around it in the shape of a pancake. Theorists believed that the eleven dwarf galaxy companions should have a diffuse, spherical arrangement, but a University of Durham team used a supercomputer to show how the galaxies could take the pancake form without challenging cosmological theory."

117 comments

  1. Next on Pancake Galactica by Anonymous Coward · · Score: 4, Funny

    The evil Egglons attack, wiping out most of breakfast.

    1. Re:Next on Pancake Galactica by AndroidCat · · Score: 2, Funny

      Why attack? Artifical food has been part of a complete breakfast for decades.

      --
      One line blog. I hear that they're called Twitters now.
    2. Re:Next on Pancake Galactica by Anonymous Coward · · Score: 1, Funny

      For the love of God, please keep quiet! George Lucas could be listening!!!

    3. Re:Next on Pancake Galactica by niteice · · Score: 1

      BREAKFAST.SYS halted. Cereal port not responding.

      Or, for you Linux types:
      rmmod breakfast cereal0: no carrier

      --
      ROMANES EUNT DOMUS
    4. Re:Next on Pancake Galactica by A+beautiful+mind · · Score: 1

      I, for one, welcome our new pancake eating overlords!

      --
      It takes a man to suffer ignorance and smile
      Be yourself no matter what they say
    5. Re:Next on Pancake Galactica by AndroidCat · · Score: 1

      You must have the cereal killer worm. (Gagh, part of this complete breakfast.)

      --
      One line blog. I hear that they're called Twitters now.
    6. Re:Next on Pancake Galactica by zonker · · Score: 0

      just as long as breakfast isn't a poppler and neither are you...

  2. Pancake? by Anonymous Coward · · Score: 0, Funny

    Pancake? How about some toast? Would you like some toast?

    1. Re:Pancake? by Anonymous Coward · · Score: 2, Funny

      "Look, I don't want any toast, and he doesn't want any toast. In fact, no one around here wants any toast. Not now, not ever. No toast!"
      "How 'bout a muffin?"
      "Or muffins! Or muffins! We don't like muffins around here! We want no muffins, no toast, noteacakes, no buns, baps, baguettes or bagels, no croissants, no crumpets, no pancakes, no potato cakes and no hot-cross buns and definitely no smegging flapjacks!"
      "Aah, so you're a waffle man!"

    2. Re:Pancake? by rob_squared · · Score: 0, Offtopic

      LISTER: (to KRYTEN) See? You see what he's like? He winds me up, man. There's no reasoning with him. KRYTEN: If you'll allow me, Sir, as one mechanical to another. He'll understand me. (Addressing the TOASTER as one would address an errant child) Now. Now, you listen here. You will not offer ANY grilled bread products to ANY member of the crew. If you do, you will be on the receiving end of a very large polo mallet. TOASTER: Can I ask just one question? KRYTEN: Of course. TOASTER: Would anyone like any toast? KRYTEN: Didn't you HEAR what I just said? TOASTER: Yes, but I thought you might have changed your mind in the meantime.

      --
      I don't get it.
    3. Re:Pancake? by Flamekebab · · Score: 1

      Rock on RD! Do we expect the film to be any good?

    4. Re:Pancake? by aslate · · Score: 1

      Do we expect the film to ever go into production?

    5. Re:Pancake? by fitten · · Score: 1

      Pipe and a pancake?
      Bong and a blintz?
      Cigar and a crepe?

  3. A pancake... by Poromenos1 · · Score: 5, Funny

    Aha, now all that remains is to find a galaxy shaped like a bottle of maple syrup!

    --
    Send email from the afterlife! Write your e-will at Dead Man's Switch.
    1. Re:A pancake... by Anonymous Coward · · Score: 2, Funny

      Aha, now all that remains is to find a galaxy shaped like a bottle of maple syrup!

      Just watch Smucker's find a galaxy shaped like a lawyer.

    2. Re:A pancake... by Tablizer · · Score: 2, Funny

      Aha, now all that remains is to find a galaxy shaped like a bottle of maple syrup!

      Mom always told you not to try science on an empty stomach.

  4. In depth ... by foobsr · · Score: 4, Insightful

    ... and more credit ... (and to enhance discussion :) ...

    Full article

    The Distribution of Satellite Galaxies: The Great Pancake

    Noam I Libeskind, Carlos S Frenk, Shaun Cole, John C Helly, Adrian Jenkins, Julio F Navarro and Chris Power

    ABSTRACT
    The 11 known satellite galaxies within 250 kpc of the Milky Way lie close to a great circle on the sky. We use high resolution N-body simulations of galactic dark matter halos to test if this remarkable property can be understood within the context of the cold dark matter cosmology. We construct halo merger trees from the simulations and use a semianalytic model to follow the formation of satellite galaxies. We find that in all 6 of our simulations, the 11 brightest satellites are indeed distributed along thin, disk-like structures analogous to that traced by the Milky Way's satellites. This is in sharp contrast to the overall distributions of dark matter in the halo and of subhalos within it which, although triaxial, are not highly aspherical. We find that the spatial distribution of satellites is significantly different from that of the most massive subhalos but is similar to that of the subset of subhalos that had the most massive progenitors at earlier times. The elongated disk-like structure delineated by the satellites has its long axis aligned with the major axis of the dark matter halo. We interpret our results as reflecting the preferential infall of satellites along the spines of a few filaments of the cosmic web.

    CC.

    --
    TaijiQuan (Huang, 5 loosenings)
    1. Re:In depth ... by Martin+Blank · · Score: 3, Insightful

      There still isn't anything about why it happens. OK, so the simulation repeats history. It would be nice if at least some explanation were provided for it. Gravity? Dark energy? Stellar cheese?

      --
      You can never go home again... but I guess you can shop there.
    2. Re:In depth ... by foobsr · · Score: 2, Interesting

      Asking why is metaphysical in (at) the end :)

      Anyway, there they have some more readable info

      CC.

      --
      TaijiQuan (Huang, 5 loosenings)
    3. Re:In depth ... by stygianguest · · Score: 4, Insightful

      From what they understand they just showed that the available theories (well, the ones they chose to use) already give an explanation of the current situation.

    4. Re:In depth ... by Anonymous Coward · · Score: 1, Informative

      How about the forces they included in the simulation? Surely they work as an explanation one level back. It gets harder if you want to know why the forces act like they do.

    5. Re:In depth ... by Duck1123 · · Score: 1

      Galaxy formation is largly determined by large globs of what scientists refer to as "Dark Butter" deep out in space.

    6. Re:In depth ... by strider44 · · Score: 1

      You know, however, that it's all just a hoax to make pancakes tax deductable...

  5. from the galactic-syrup-lay-undiscovered dept. by Anonymous Coward · · Score: 0

    OMG, you're so original! Ripping off jokes made by CmdrTaco makes you so witty!

    1. Re:from the galactic-syrup-lay-undiscovered dept. by Anonymous Coward · · Score: 0

      Wow, you are so Informative +1 and Insightful +1 yet you are still able to keep your sense of humor and be Funny +1. Its a pity that your post is completely Offtopic -1 and probably counts as Flamebait -1. Maybe if you were a little more Interesting +1, your post wouldn't be so Overrated -1.

  6. So therefore... by Z0mb1eman · · Score: 4, Funny

    It's bunnies all the way down?

    --
    ClutterMe.com - easiest site creation on the Net. Just click and type.
    1. Re:So therefore... by Zorilla · · Score: 4, Informative

      Damn, beaten to the Oolong joke.

      For moderators: Oolong the Pancake Rabbit

      --

      It would be cool if it didn't suck.
    2. Re:So therefore... by Anonymous Coward · · Score: 0

      Is he related to the hamster dance ?

  7. Short answer by Anonymous Coward · · Score: 5, Funny

    Our local cluster is a franchise of IHOP (intergalactic house of pancakes).

    1. Re:Short answer by Tango42 · · Score: 1

      That's be iHop... Apple have never been one to miss an opertunity...

  8. In other news.... by spiderworm · · Score: 4, Funny

    ... researchers are still working on the mystery of the cosmic sausage and eggs, as well as new puzzling information that seems to indicate the presence of a Great White Handkerchief... or maybe it's a napkin?

  9. Without challenging cosmological theory by Anonymous Coward · · Score: 4, Funny

    Dark Syrup explains galactic pancake mystery.

    1. Re:Without challenging cosmological theory by Anonymous Coward · · Score: 0

      hahaha!

  10. Milk? Pancake? by Anonymous Coward · · Score: 0, Funny

    Never know astronomy is closely related to gastronomy. Hmmmm... pancake, milk *drool* drool*

    What's next? Universe muffins? Bacon clusters?

    1. Re:Milk? Pancake? by Anonymous Coward · · Score: 1, Funny

      A MILKY WAY Galaxy perhaps...?

  11. Remind you of anything? by Daxx_61 · · Score: 4, Interesting

    This sounds a little like planetary formation. What if these 'halos' were really rings, due to some sort of spin in the original setup? Do they have to be a 3-dimensional halo? I am not an astronomer, but it sounds reasonable to me - could someone please explain this?

    --
    Quoth the server, "404."
    1. Re:Remind you of anything? by Anonymous Coward · · Score: 1, Funny

      The halos are, in fact, rings left by an ancient race of beings who were far more technologically advanced. There appear to be seven in total, although one seems to have been destroyed recently...

    2. Re:Remind you of anything? by Randym · · Score: 1
      This sounds a little like planetary formation. What if these 'halos' were really rings, due to some sort of spin in the original setup? Do they have to be a 3-dimensional halo?

      IANAA, but it seems reasonable to me that a 3-D rotating ellipsoid *would* collapse (due to gravitation) along its smallest axis -- the one running "vertically" through the center of the galactic mass -- thus "flattening out" in the other two dimensions.

      --
      DNA is a Turing machine. You, however, being dynamic and emergent, are not.
  12. Way to go, University of Wherever by Douglas+Simmons · · Score: 0, Flamebait

    It makes me smile to see some kids doing a group project at some random college make an apparently major discovery that solves some mystery that the pros at NASA couldn't handle. Stuff like this and that X Prize thing shows that there are indeed a few things citizens are capable of handling. High five, kids. NASA, get on the ball.

    1. Re:Way to go, University of Wherever by Martin+Blank · · Score: 3, Informative

      How much of this kind of research does NASA actually do? It seems that they largely put the satellites in place and maintain them, and universities handle the data analysis.

      --
      You can never go home again... but I guess you can shop there.
    2. Re:Way to go, University of Wherever by Anonymous Coward · · Score: 2, Informative

      University of Durham http://en.wikipedia.org/wiki/Durham/

      Just 'cause it's not in the US...

    3. Re:Way to go, University of Wherever by chman · · Score: 0, Flamebait

      Yeah, Durham is a great university. With this kind of research going on, they've definitely attained a reputation that leaves them neatly perched a sliver above mediocrity.

      I keed, I keed. They were my backup-backup choice, and if they hadn't been so shortsighted as to put the uni that far north, I might have gone to their open day.

      Maybe.

      --
      This comment was formatted for readability, but I forgot the line break tags
    4. Re:Way to go, University of Wherever by kfg · · Score: 5, Informative

      NASA is about rockets. This isn't the sort of stuff they do really do. They help supply data to astronomers/cosmologists/physicists who apply to them, and who, largely, are affiliated with universities and are not "kids."

      Dr. Feynman at CalTech and Dr. Sagan at Cornell, for instance, who were both rather famously at odds with NASA more often than not.

      "Citizens" have always handled the bulk of astronomical research.

      Because more often than not NASA is the necessary enemy of astronomers. It is a government agency, run for the government's purposes, complete with a government beauracracy, and only provisionally interested in theoretical science at all.

      But they own Hubble.

      I might also point out that these "kids" weren't even in America. England has a university or two worth a damn that might object to being catagorized as "random", and four or five smart people in them. Germany, China, Australia, and hell (as it were), even the Vatican have quite capable cosmologists of their own.

      NASA isn't the center of the universe.

      KFG

    5. Re:Way to go, University of Wherever by Anonymous Coward · · Score: 2, Informative

      NASA doesn't really specialize in science. It specializes in complex engineering feats where outside scientists run the experiments. When the Mars Exploration Rovers landed on Mars, the project was run by JPL engineers, but the science data was evaluated by scientists at various institutions (initially the ones who helped design the science payloads).

      NASA gets credit for many scientific discoveries due to the fact that they wouldn't be made without the NASA hardware. But NASA does not employ the scientists who make the discoveries (except in a few odd projects like asteroid impact research).

    6. Re:Way to go, University of Wherever by Anonymous Coward · · Score: 1, Informative

      Sadly, this is not some kids at some random college. Durham is a very well respected university in the UK and Prof. Frenk is extremely well known. He is the fifth most cited physical scientist in the UK and the second most cited space scientist in the world. (The Brits really like to rank things ...) http://star-www.dur.ac.uk/~csf/homepage/cv.ps

    7. Re:Way to go, University of Wherever by Tim+C · · Score: 4, Insightful

      Well, maybe *you've* never heard of the University of Durham, but it's one of the foremost universities in the UK, and the Physics group there is extremely well-respected.

      This isn't "some kids doing a group project", this is proper academic research; you may have heard of that...

    8. Re:Way to go, University of Wherever by Anonymous Coward · · Score: 0

      Well, if I breathe in quickly, it measures about 4 and a half inches (about 11.5 cm for Brits). Thats a decent measurement, right? As long as I beat Prof. Farnsworth at the University of Cambridge (4 inches), I will still be respected by other astronomers.

    9. Re:Way to go, University of Wherever by Tim+C · · Score: 1

      You need to remove the trailing / on the link: http://en.wikipedia.org/wiki/Durham

    10. Re:Way to go, University of Wherever by Anonymous Coward · · Score: 0

      Yes, its not Proper Academic Research(TM) unless there is an ivory tower and a bunch of PhD carrying snobs with their nose in the air thinking they are somehow better than everyone else.

    11. Re:Way to go, University of Wherever by avsed · · Score: 2, Informative

      You are absolutely kidding right? I've studied at Durham, UK (Carlos Frenk was my Astro lecturer), QM, London, and Stanford, US, and they all have their fair share of smart people. Calling Frenk, or indeed any of these guys "kids" is way out of line. Than again, I could just chalk it up as yet another example of American insularity. (Go ahead, mod me flamebait, I just don't take kindly to the "kids" vs. "pro" and "university of whatever" thing - it's rude and naive).

      Dan

    12. Re:Way to go, University of Wherever by Anonymous Coward · · Score: 0

      You've studied at Durham then? :-)

  13. Under new theory, Big Bang to be renamed... by Anonymous Coward · · Score: 0

    ...the Grand Slam.

  14. Before anyone thinks of putting dark matter syrup by Anonymous Coward · · Score: 3, Funny

    ...on this pancake, Smucker's already has a patent on it.

  15. Well... by rob_squared · · Score: 2, Funny

    ...there *are* certain galaxies that look like oranges. http://www.eso.org/outreach/press-rel/pr-2003/imag es/Phot32/phot-32a-03-normal.jpg

    --
    I don't get it.
    1. Re:Well... by Anonymous Coward · · Score: 0

      Except that Eta Carinae is NOT a galaxy.

  16. Silly scienticians! by Flamekebab · · Score: 2, Interesting

    without challenging cosmological theory
    Isn't it supposed to be about challenging current theories?

    1. Re:Silly scienticians! by Anonymous Coward · · Score: 0

      Scienticians? How about Scientologists(R)? They have the theory you are looking for(TM).

    2. Re:Silly scienticians! by Flamekebab · · Score: 1

      Physicologisers?
      Astronomicians?

    3. Re:Silly scienticians! by Anonymous Coward · · Score: 0

      Dread Lord Geologist Robersts of the School of Dire Faults
      Lord High Botanist Extraordinaire Bob of USFS Station Dead Wood

    4. Re:Silly scienticians! by bloggins02 · · Score: 2, Insightful

      Isn't it supposed to be about challenging current theories?

      No, it's supposed to be about parsimony. If you find an explanation of a phenomena that fits with current theories, that's favorable to throwing out a bunch of current theories just to explain your phenomena.

      It's called "simpler." We like simpler.

  17. A Quick Question by MankyD · · Score: 2, Interesting

    I've got a slightly more than average knowledge base on cosmology (though maybe not more than your average slashdotter). I've read a few books, but one thing I've never cleared up: Why do galaxies form in flat spirals and pancaks, and not in gravitationally stable spheres? Is there a simple reason I'm missing?

    --
    -dave
    http://millionnumbers.com/ - own the number of your dreams
    1. Re:A Quick Question by MankyD · · Score: 2, Funny

      Mod me down - I just remembered why. I'm an idiot.

      --
      -dave
      http://millionnumbers.com/ - own the number of your dreams
    2. Re:A Quick Question by imsabbel · · Score: 4, Informative

      Angular Momentum

      If you have a total angular momentum of 0, you get an eliptical galaxy. All stars have totally random orbital orientations around the center, so it gives an elipsoid. it COULD be a sphere (but what do you mean with gravitational stable? all galaxies are dynamic), but the chances are rather slim).
      If there is a angular momentum, it will create a disc simply because thats a lower energy state with the same angular momentum compared to a sphere.

      --
      HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
    3. Re:A Quick Question by Pedrito · · Score: 2, Interesting

      I'll grant that I'm no a math whiz, so I don't know the mathematics involved, but the reasons seem so obvious as to make me wonder how this could possibly challenge "cosmological theory." Most galaxies are pancake shaped. Most solar systems are pancake shaped. As you mentioned, nothing is really "gravitationally stable." I mean, if there's any movement at all, things are going to coalesce into a pancake shape eventually, unless all the movement is completely canceled out by opposite forces/movement, which is just statistically incredibly unlikely.

    4. Re:A Quick Question by Bastian · · Score: 4, Interesting

      So what you're saying is that you have to have the matter in the galaxy orbit (more or less) around a common axis, like in our solar system.

      What would cause this to happen, instead of there being a bunch of randomly-oriented orbits?

      (I suppose I am making the critical assumption that the distribution of matter immediately after the big bang was uniform, and I'm sure any cosmologist would be happy to smack me down over that, but I'll ask anyway.)

    5. Re:A Quick Question by Anonymous Coward · · Score: 1, Insightful

      Even if you have a bunch of uniformly randomly-oriented orbits, there is always at least a little angular momentum in some direction; you never get perfect statistical cancellation to zero. This angular momentum is conserved, and as the cloud of matter collapses gravitationally, the rotational effect is amplified (like a spinning figure skater pulling in his/her arms).

    6. Re:A Quick Question by khayman80 · · Score: 3, Insightful
      First of all, the galaxy is believed to have condensed from a much larger cloud of primordial hydrogen and helium (it's theorized that supermassive black holes played a large role in this process). Because the proto-galaxy condensed from something MUCH larger, its moment of inertia reduced dramatically (rather like an ice-skater drawing her arms in to spin faster). This caused the angular rotation of the galaxy to increase around whatever axis the angular momentum pointed originally (which I would imagine is completely random for each galaxy).

      So each galaxy should have non-zero angular momentum. This doesn't mean that there shouldn't be ANY spherical-like orbits, just that the majority of objects orbit in the "pancake" that is perpendicular to the axis of rotation. Here's the punchline: over billions of years, the objects that are NOT orbiting in the galaxy's pancake have close encounters with the more numerous objects in the pancake, and are either flung out of the galaxy or put into more normal orbits. The same process accounts for the fact that all planets in the Solar System orbit in a common plane (called the ecliptic plane).

      As for elliptic galaxies, my impression was that they are the result of low-speed collisions between two spiral galaxies of roughly the same size. The two pancakes then combine to form a diffuse cloud of strars. For instance, when the Milky Way impacts Andromeda in 2 billion years (or is it 3? I can't remember), the result should be an elliptic galaxy if I understand the dynamics correctly.

    7. Re:A Quick Question by ph43drus · · Score: 2, Interesting

      IAAP (I am a physicist), and the gravitationally stable spheres is a problem. That's what this study was looking at.

      The bright, visible, normal matter forms into a disk in every galaxy we see. This cannot be explained with Newtonian gravity (or Einsteinian, for that matter). You see, when you just stick the normal matter in a simulation to check the evolution of a galaxy, it doesn't stay in the disk shape. To get the simulations to work (meaning, predict disk galaxies), you have to put a spherical halo of dark matter around the galaxy. With the dark matter there, it works perfectly.

      The other option is that we're completely screwed up in terms of our beliefs about gravity. However, we haven't gotten any clean results using alternate formulations of gravity.

      So the answer is, to the best of my knowledge, galaxies are disks because they either have (a) halos of dark matter or (b) our formulation of gravity is extremely flawed. Both of these answers are the current big embarrassments in physics. Both are bad answers. I haven't seen an alternate to gravity that works, and dark matter is a cop out.

      From looking at the article, it looks like they've done a huge simulation taking the dark matter halo bit to the extreme and finding that it correctly predicts a flat arrangement for the satelite galaxies.

      This is not proof of dark matter, it merely shows that it is the appropriate adjustment to gravity to explain some of the phenomena in the sky. What this actually means is that the correct answer for "why are galaxies disks?" will likely be the same answer for the pancake mystery. So, the authors did not actually solve the problem, they just showed that the current, in vogue kludge works for the pancake mystery too.

      I'm, personally, quite sick of hearing it held up as an explanation as if it is the end all be all of fixing cosmology. It is a stupid cop-out with nothing to back it up. There is no experimental evidence for it. We have yet to find anything that could be dark matter (and there are people looking very hard to find it). Other theories don't have anything in them which could be dark matter (no particle theorist has come up with anything, and certainly not the high energy experimentalists). It is a big ol' strap of duct tape to fix a gaping hole in cosmology. There is nothing backing it up. Quite frankly, it's starting to sound like the Æther to me. And we all remember where that got us.

      Jeff

    8. Re:A Quick Question by Anonymous Coward · · Score: 0

      Actually, most galaxies are spherical, or at least ellipsoidal (which is just a squishy sphere, after all). The spiral galaxy accounts for a minority (though still significant) portion of the galactic population. Furthermore, by far the largest and smallest galaxies are ellipticals.

      The whole "gravitationally stable" is a red herring, but otherwise, the universe turns out to be not quite as weird as you might think. Weird, eh?

      As for why they form discs, some of the other posters have good explanations for that, although I'm not entirely convinced that they aren't overly simplified.

    9. Re:A Quick Question by Bastian · · Score: 2, Interesting

      I am actually glad to hear that. . . I don't know enough about current physics to really make any sort of valid judgement on the theory. (I frequently get the feeling that I don't even understand the basic ideas behind relativity very well.) But the idea of dark matter always seemed to me to be rather fishy, sort of like the old crystal spheres that held the planets aloft.
      I mean, they're both explanations for physical phenomena that were unexplainable under the model for how the universe worked at the time they were created, and they are both these sort of hand-wavey firmaments that don't seem to be something we can see or touch, but that we know to be there because they happen to magically make everything work. And dark energy feels like another hasty band-aid on top of the whole mess, like epicycles. My intuition is to think that the last few times people found problems with the theory, it turned out that the fundamental model was wrong, not that we needed to fill the universe with more crap (crystal spheres, aether, thunder gods, what have you), and to think that maybe it isn't so silly to try and extrapolate that pattern.

    10. Re:A Quick Question by Anonymous Coward · · Score: 2, Interesting

      I am a physicist too, and I suggest you review some astrophysics.

      Dark matter is more than a "cop out". If dark matter only explained one thing, it might be a cop-out, but it simultaneously explains observations in cosmology, observations of galactic rotation curves, and large-scale structure formation -- all independent phenomena. This is a nontrivial accomplishment.

      It is also not true that no particle theorists have come up with anything which could be dark matter. Quite the opposite -- they have too many theories. The leading candidates are axions (thought to be needed to solve problems with CP symmetry in QCD) and supersymmetric partners. Experiments are underway to try to detect these.

      As for discs, spheres of matter with some net angular momentum will form into rotating discs without dark matter, once there's a region locally dense enough to collapse. But dark matter is needed to explain our observations of the specific way in which disc galaxies rotate. It is also needed to explain how the universe got clumpy enough for matter to start collapsing into galaxies in the first place.

      Dark matter is the "new aether"? You could have said the same to people who proposed that an unseen body (Neptune) was perturbing the orbit of Uranus. But people looked, and they eventually found that there really was something there. And this was based on only one kind of observation, the orbit of Uranus, not cosmological observations plus galactic rotation observations plus galaxy cluster observations, all of which are explained by dark matter.

    11. Re:A Quick Question by nimblebrain · · Score: 2, Interesting

      Hear, hear.

      I've been quite surprised at the influx of "odd" observations over the past few years; I certainly wasn't expecting local pancake structures.

      You raise a pretty good point, though, on the structure of disks, large and small, in the first place.

      Plasma physicists jump up and down that the in-vogue theories treat large-scale magnetic fields and currents as non-existent, as though charge must cancel out on the large scale, therefore it has no effect. Sometimes, they make a good point - some of the disk systems do resemble dynamos.

      Some of the papers I've read in passing on "push" gravity theories estimate that the force of gravity is proportional to 1/d**2 locally, but trends to 1/d on the outsides of the galaxy. Otherwise, there's a lot of unseen matter there (and we haven't seen anything resembling the high-velocity clouds gathering on the edges of the galaxy)... or, alternately, we're ignoring a dynamo effect.

      Or... etc. (Assuming we stop before postulating that angels sit on the edge fanning galaxies with their wings ;)

      It's the bank of poorly-explained pieces that will lead us to our next big theoretical breakthrough (or revolution) - but it takes some special vigilance to keep track of what hasn't actually been explained properly, and what's been merely papered over.

      Too many tweaks. They should have realized something was wrong sometime between inflation theory, and dark-energy-requiring ever-increasing-acceleration theory. Plenty of duct tape on things already :)

      By the way, speaking of aether... ;)

      I can understand the establishment position somewhat... it's either duct tape or anarchy. There's got to be a standard to measure against, but if the explanations start stretching thin, they need an exit strategy.

      If that day comes, they will need to exit to something, though. What's out there that can explain the pancakes at multiple scales of the universe and other phenomena as well?

      Perhaps they need to take a page out of other research and development, and apportion some funds to "blue sky" research.

      The biggest dividends will come from research that's reviewed for logic, self-consistency and explanation of phenomena without regard to how well it fits into prior patterns. Pro-Ams and people in fields with more easily measureable results (applied sciences, for one) realize these benefits, but being in a field where so many assumptions have to be made to interpret the results in the first place make this next to impossible for the theoreticians to condone dissent.

      Everybody's MMV :)

      -- Ritchie

      --
      Binary geeks can count to 1,023 on their fingers :)
    12. Re:A Quick Question by ph43drus · · Score: 0

      Dark matter is more than a "cop out". If dark matter only explained one thing, it might be a cop-out, but it simultaneously explains observations in cosmology, observations of galactic rotation curves, and large-scale structure formation -- all independent phenomena. This is a nontrivial accomplishment.

      It is a non-trivial accomplishment, but a math problem has been solved, not a physics problem. The numbers line up, but we have a big missing hole which we can't detect.

      It is also not true that no particle theorists have come up with anything which could be dark matter. Quite the opposite -- they have too many theories. The leading candidates are axions (thought to be needed to solve problems with CP symmetry in QCD) and supersymmetric partners. Experiments are underway to try to detect these.

      All of the theories fall into two catagories: not enough of them around to account for the dark matter, or they are theorized but undiscovered. Axions fall into the latter catagories.

      I'm an experimentalist, and there just isn't enough ground to stand on here. We haven't seen dark matter. I'll believe it once we've seen it.

      Dark matter is the "new aether"? You could have said the same to people who proposed that an unseen body (Neptune) was perturbing the orbit of Uranus. But people looked, and they eventually found that there really was something there.

      Beautiful example! I couldn't have thought of a better one! Le Verrier was the one who did the calculation to discover Neptune. With that grand success, he did the same thing for the perturbations in Mercury's orbit and named the predicted planet "Vulcan". There were many false observations of Vulcan before Einstein explained Mercury's orbit with relativity. Le Verrier's calculations were about equally sketchy in both cases, and both yielded observations confirming the existence of a planet. The difference? He was right the first time, and wrong the second.

      And this was based on only one kind of observation, the orbit of Uranus, not cosmological observations plus galactic rotation observations plus galaxy cluster observations, all of which are explained by dark matter.

      The mathematical explanation is there, but we don't have the experimental evidence, and it's embarrassing. It bugs me when it's presented as "Nothing to see here, it's Dark Matter, we've got the problem solved, 100%", which is how the press presents it. At my school, amongst the physicists, we grin sheepishly over not having a better or more complete answer on this one.

      There is still the possibility of an alternate explanation to come out. In fact, what I was saying, since the dark matter correction has been so successful, this points to the fact that all these phenomena will likely be explained using the same mechanism whether it ends up being dark matter or not.

      Another case in point, Copernicus' heliocentric system still used epicycles. He believed firmly in perfect circular motion, and put all the planets in perfectly circular orbits around the sun. Then, to correct for the deviations which we now know come from the fact that orbits are elliptical, he put each planet (except earth) on a small epicycle. Both Copernicus' and Ptolemy's systems had a 17 year glitch, where every 17 years, the whole system would significantly mispredict planetary locations. However, had Copernicus been "more Copernican" and put an epicycle on earth's orbit, the glitch would have gone away. The point being, do you believe in elliptical orbits, or perfect circular motion with two cycles, a great circle and an epicycle? In the 17th and 18th centuries, you wouldn't have been able to tell the difference had Copernicus gotten earth right.

      To get to my comment about dark matter being the "new æther": at the end of the 19th centur

    13. Re:A Quick Question by Anonymous Coward · · Score: 0

      It is a non-trivial accomplishment, but a math problem has been solved, not a physics problem.

      Spoken like an experimentalist. It's a theory, it makes predictions whose observations have been confirmed. It hasn't been confirmed as much as people would like, and there are still a number of theories that can account for the data, but that doesn't place it in the realm of "pure mathematics".

      All of the theories fall into two catagories: not enough of them around to account for the dark matter, or they are theorized but undiscovered. Axions fall into the latter catagories.

      That's true, but don't pretend like there are no theories out there!

      Le Verrier's calculations were about equally sketchy in both cases, and both yielded observations confirming the existence of a planet. The difference? He was right the first time, and wrong the second.

      I am well aware of that. In fact, I usually drag it out myself in discussions of dark matter. The point is that EITHER explanation is potentially valid: unseen matter, or modified gravity. However, in the case of dark matter, a LOT of alternate gravity theories have been tried, and have been spectacularly unsuccessful in accounting for the observations. The closest anyone has come is MOND, and that's far more ad-hoc than even dark matter.

      The mathematical explanation is there, but we don't have the experimental evidence, and it's embarrassing.

      We have plenty of experimental evidence. We just don't have direct detection. (It's even possible that we might not ever have direct detection; nobody ever said that all particles have to couple strongly enough for us to detect that way, and in fact it's not that hard to write down fairly natural theories with even sterile particles that only interact gravitationally.)

      Well, indirect evidence isn't as nice as direct detection, but it's not nothing, either. Taylor and Hulse got the 1993 Nobel for indirect detection of gravitational waves. Black holes will probably never be directly detected, by their very nature, but we have good reasons to believe they exist. And so on.

      It bugs me when it's presented as "Nothing to see here, it's Dark Matter, we've got the problem solved, 100%", which is how the press presents it.

      It very likely is dark matter. We just don't know what kind of dark matter, which means the problem is far from 100% solved.

      There is still the possibility of an alternate explanation to come out. In fact, what I was saying, since the dark matter correction has been so successful, this points to the fact that all these phenomena will likely be explained using the same mechanism whether it ends up being dark matter or not.

      This doesn't follow. Again, it's a very non-trivial accomplishment to solve a number of independent phenomena with one mechanism. Every attempt so far to do so other than dark matter has not only failed to account for all of them, but has been inconsistent with at least some observations. (Again, with the exception of MOND, although things aren't looking to good for it; Bekenstein has produced the only relativistic theory of MOND known, which is quite convoluted, and will probably require fine-tuning to agree with observations.)

      Another case in point, Copernicus' heliocentric system still used epicycles.

      Oh good grief. You wouldn't believe how tired I am of Slashdotters equating every theory in physics -- dark matter, black holes, whatever -- with epicycles. Dark matter is not epicycles. With epicycles you could basically get any answer you wanted -- it was essentially curve fitting with Fourier analysis. Want a better answer, add more epicycles. Dark matter theories make detailed, specific p

  18. So... by unsinged+int · · Score: 4, Funny

    when's the galaxy due to flip over?

    1. Re:So... by Anonymous Coward · · Score: 0

      6.5 billion years ago. We're still stuck to the ceiling.

  19. Cosmic griddle? by tinrobot · · Score: 1

    I wonder if this has anything to do with the conjectured cosmic griddle, which heats the primordial galactic batter and makes it te golden hue of our stars and sun?

  20. How was never a mystery... by Jace+of+Fuse! · · Score: 1

    It was my understanding that HOW it got to be that shape was never a mystery. The real mystery was who in the hell was holding that huge spatula, and where did they get it in the first place?

    --

    "Everything you know is wrong. (And stupid.)"

    Moderation Totals: Wrong=2, Stupid=3, Total=5.
  21. Wait a minute now... by hyperm0g · · Score: 1

    An elven dwarf galaxy? Now that's just perposterous!

  22. Calvin and Hobbes Reference by Brain+Stew · · Score: 0, Redundant

    Great, know can we solve the great spaghetti incident?

    --
    "Here's a spoiler: You're will die alone."-Triumph the Insult Comic Dog
    1. Re:Calvin and Hobbes Reference by mmkkbb · · Score: 1

      *ahem*

      the spaghetti incident is a guns n roses album.

      calvin had a NOODLE incident at school

      --
      -mkb
    2. Re:Calvin and Hobbes Reference by Anonymous Coward · · Score: 1, Funny

      nobody can prove that!

    3. Re:Calvin and Hobbes Reference by mmkkbb · · Score: 1

      If only I could mod this up.

      --
      -mkb
  23. Re:pancakes and dwarfs by Lord+Pillage · · Score: 1

    Or maybe it's a tuesday??

    --
    try { Signature mysig = new CleverAttempt(); } catch(NonCleverSignatureException e) { postanyway(); }
  24. Had to be done by taylortbb · · Score: 2, Funny

    Yes, but is it perpendicular?

    (ducks)

    1. Re:Had to be done by PakProtector · · Score: 1

      Could someone please explain this?

      --

      Edward@Tomato - /home/Edward/ man woman
      man: no entry for woman in the manual.
      "Qua!?"

    2. Re:Had to be done by taylortbb · · Score: 1

      View the "Broken Into Song" link on the "Hitachi Goes Perpendicular" article.

  25. This may very well be redundant... by thegnu · · Score: 2, Funny

    Theorists believed that the eleven dwarf galaxy companions should have a diffuse, spherical arrangement

    Sounds like someone's been watching the Lord of the Rings box set a wee bit much.

    --
    Please stop stalking me, bro.
  26. The most irritating part of being an astronomer by Simonetta · · Score: 2, Interesting

    The most irritating part of being an astronomer must be constantly defending the allocation of millions of dollars of public funds on whatever it is that they do.

    A major new theory in regards to the shape and spacing of galaxies; what difference does it make to anyone?

    Any bible-thumping corrupt two-bit schmuck of a politician can come up with a reason why the millions of dollars spent on astronomical research would better be directed towards one of his campaign contributers. And there are lots of those politicians nowdays.

    So how actually do the astronomers keep all this money flowing their way? I would suspect that astronomy is 80% math and computer programming now instead of primarily star-gazing.

    In the past, it wasn't this hard to justify the astronomers. Gods ruled the stars; kings ruled the people by the grace of the gods; astronomers interpreted the movement of the stars to convince the people that the gods still favored the king, and the king saw to it that the astronomers got plenty of money.

    Astronomical research was important in navigation and agriculture. When to plant and which direction to steer when out-of-sight of land was critically important. But real extraterrestial knowledge came slowly. It was only four hundred years ago that Westerners realized that the Earth moved around the sun.

    Today the most interesting about astronomy isn't theories about objects billions of miles away, it's how astronomers justify spending millions of dollars looking at objects billions of miles away.

    1. Re:The most irritating part of being an astronomer by magarity · · Score: 1

      I'm just glad you're neither bitter nor disillusioned.

    2. Re:The most irritating part of being an astronomer by Anonymous Coward · · Score: 0

      is defending your funding... ...If you get funding at all. It's not so hard to get money to play with some big telescope for a bit, but it's much harder for the astrophysicists (us dudes with the computers and simulations) to justify our existence within academia.

  27. Black donut holes eat you! by Anonymous Coward · · Score: 0

    Or at least Homer Simpson. :-)

  28. Too early by Anonymous Coward · · Score: 0

    Milky way? Dwarves? Pancakes?

    Where the hell is my coffee, I must still be dreaming.

  29. "Simpsons Did It!" by aftk2 · · Score: 1

    Hawking: Your theory of a donut shaped universe is intriguing Homer, I may have to steal it.
    Homer: Wow, I can't believe someone I never heard of is hanging out with a guy like me.

    --
    concrete5: a cms made for marketing, but strong enough for geeks.
  30. Space pancakes are no big deal. by TheLittleJetson · · Score: 1

    Anyone who's ridden Space Mountain at Disneyland knows of the existance of Space Cookies

  31. Homer's take by Rixel · · Score: 1

    Mmmmmmmmmm......

    Universalicious

    --
    Never play chicken with a passive aggressive.
  32. Without challenging Star Wars history by Jesus_666 · · Score: 1

    Darth Syrup saves Episode III.

    --
    USE HOT GRITS WITH STATUE OF NATALIE PORTMAN (NAKED AND PETRIFIED)
  33. Universal Delicacies by magnus_1986 · · Score: 1

    Milky way
    Pancakes
    Galaxy

    What next? Black holes look like blackcurrents?

    --
    My last sig was ridiculed
  34. mod down, unrelated to parent post by Anonymous Coward · · Score: 0

    What does your post have to do with the parent? Nothing! You're a karma whore seeking attention, nothing else. Definitely mod down.

  35. In other news... by Anonymous Coward · · Score: 0

    SETI recieved its first transmission from extraterrestrial life:

    "Click click bloody click PANCAKES!"

  36. Ironically... by mbrother · · Score: 1

    I just ended my Friday lecture on the local group of galaxies. They're the best measure of the frequency of galaxies out there in the universe, since many dwarf ellipitcals (very common in the local group) are difficult or impossible to see at greater distances.

    --
    Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
    1. Re:Ironically... by Anonymous Coward · · Score: 0

      Is that really true? I mean, don't you get an observational selection effect by the fact that you can only observe the galaxies in our local neighborhood? I mean, sure, you can assume that the universe is isotropic at those scales, but there have been numerous nasty surprises in the past on that count. Furthermore, galaxies farther away and further back in time and all that, observationally, so how does studying our local neighbors help us make predictions about those kind of things? Just curious.

    2. Re:Ironically... by mbrother · · Score: 1

      The observation bias of not being able to see dwarf ellipticals is clear. There's also a statistical bias, related to what you're talking about, in that you're looking at a small part of space. The thing is, however, on larger scales, you're going to start coming across *rarer* objects (e.g., very luminous galaxies). So if you're interested in the most common objects, you need to look locally. To get a complete picture, including the rarest objects, you must look deeply and remotely.

      Look far enough away, and you will start to see evolutionary effects, sure. But look at a field of distant galaxies, you'll notice all the bright ones. But I guarantee there will be lots more little, faint, overlooked galaxies.

      Astronomers quantify this as the galaxy luminosity function. It's difficult to get the faintest end, and the brightest end, for the reasons discussed above. You do the best you can.

      --
      Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
  37. The key is collapse along a filament by StupendousMan · · Score: 1

    The key to this idea is that, given a particular set of initial conditions for the perturbations of density after the Big Bang, matter becomes concentrated in long, thin, filamentary structures. When those structures collapse under the influence of gravity, the result is group of galaxies -- in this, one big one and several small ones -- stretched out along the axis of the early filament(s). So, rather than being distributed all around the big galaxy in a spherical cloud, the little galaxies are arranged in a very loose flattened bunch.

    Now, all this depends, of course, on the particular distribution of density perturbations in the early universe. All we astronomers can do is pick some particular model and follow it to see how it evolves. I'm not aware of good reasons for requiring any particular distribution from first principles; people just pick reasonable models that are somewhat easy to describe.

    --
    Michael Richmond "This is the heart that broke my finger."
    mwrsps@rit.edu http://stupendous.rit.edu
  38. Re:Before anyone thinks of putting dark matter syr by Greyfox · · Score: 1
    Well figuring out how to pour syrup on a galaxy sized pancake certainly WOULD be innovative...

    Mmm... pancakes...

    --

    I'm trying to teach myself to set people on fire with my mind... Is it hot in here?

  39. Did anyone else notice... by -kertrats- · · Score: 1

    Anyone else notice that their picture of the Milky Way galaxy has 5 arms? If this is coming from the crack team of scientists, I'm a bit suspicious.

    --
    The Braying and Neighing of Barnyard Animals Follows.
    1. Re:Did anyone else notice... by Anonymous Coward · · Score: 0

      Considering that no one (we know of) has gotten a chance to look at the galaxy from the OUTSIDE, and that there is so much dust obscuring our view from INSIDE, not to mention the difficulty in getting accurate distance data beyond about 10-20 parsecs (the galaxy is like 30,000 parsecs across), then I'd say they're as close to the truth as you are, if not more so.

      We can be pretty sure from what we've seen so far that there are SEVERAL arms, many of which are just small "sub-arms". Add to that the fact that the galaxy is spinning, and that the arms we have today may not be the same arms we'll have in a billion years, nevermind what assorted dwarf galaxies crashing into us will do, or when Andromeda eats us a few more billion years down the road, just before the sun collapses.

      So how many arms did you think it was supposed to have? 2? 100? The answer is (probably) somewhere in the middle.

    2. Re:Did anyone else notice... by Anonymous Coward · · Score: 0

      Actually, recent studies (in the last decade or so) show the Milky Way will eat the Andromeda, and that the Milky Way is actually bigger than the Andromeda (has to do with new studies into the actual size of the galactic disc, which turned out to be missing the edges due to weird dark matter effects and things like that). Go home team! :)

      Right on with the "outside the galaxy" bit, though. I don't think they're actually using a picture of the Milky Way, they're just saying "this is a picture of a spiral galaxy, which the Milky Way might look like". Incidentally, we do have rough partial pictures of the Milky Way developed from radar mapping of various spectral lines, and I think someone even managed to get some light reflected off dust clouds for spectroscopic purposes, but nothing photographic like the "you are here" T-shirts you sometimes see.

  40. Which supercomputer? by rice_burners_suck · · Score: 1

    Does anyone know which supercomputer they used? I am interested to know because I thought that one that was composed of I don't know how many dual G5s was supposed to be used for astronomy research and the like...

  41. Ob. Simpsons Quote by adyus · · Score: 0

    "mmm...paancakes...."

    Brought to you by Galaxy Simpsons

  42. Here in Western Australia... by leonbrooks · · Score: 1

    ...they do guided tours, rent out the names of stars, and get most of their ancilliary equipment donated to them and off the books.

    I do wish some of the PHB industrialists funding the pork-barrelling would wake up to the incredible industrial potential of space, and decide that they have to take a risk and get a piece of pie in the sky right now rather than when they die (and they've got a rude shock coming at that point, along the lines of: "Oi! I left you lot with a perfectly good planet, and now look at it!").

    --
    Got time? Spend some of it coding or testing
  43. "(not) Solved" by Penguinoflight · · Score: 1

    The problem here, is that in all likelyhood a galaxy shouldn't be shaped like a pancake, that is unless someone put it together specifically to look that way.

    Argueing there's a logical complex reason why the milky way is a pancake is like arguing there's a complex reason that only 6 cookies remain in the jar, when your mother placed 20 there.

    Try as you might, you're not going to convice your mother that you didn't eat 14 (choak) cookies. The explanation is simple enough, and without solid evidence that someone else ate them, or they came into contact with antimatter cookies, your left withthe simple explanation.

    False assumptions (ie, all matter "spawned" from one central location) have no more credibilty if you come up with an unbelievable story of how this might have happend. Simplicity rules here, and if we're really going to use the scientific method, we should be looking back at what most likely did happen, not looking for cop-outs to explain poor assumptions and bias.

    --
    "And we have seen and do testify that the Father sent the Son to be the Savior of the World"
    1 John 4:14
  44. I, for one, welcome... by dacaldar · · Score: 1

    our new yummy buttermilk-flavoured overlords!