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Spiral Galaxy Spins the Wrong Way

Ant writes: "The New Scientist has an article about a galaxy in the constellation Centaurus is puzzling astronomers by spinning in the wrong direction. NGC 4622 has bright twisting arms containing newborn stars and lies 111 million light years away."

51 comments

  1. Wrong way? by SpaceLifeForm · · Score: 2, Interesting

    It could be two galaxies that happen to be lined up from our point of view.
    Space can be tricky, there is more there than meets the eye.

    --
    You are being MICROattacked, from various angles, in a SOFT manner.
    1. Re:Wrong way? by jeffy124 · · Score: 0

      i agree. what if we're looking at the galaxy from the wrong side? When you look striaght on at a clock, you see the hands move clockwise. The view from the back of the clock is counterclockwise. How do we know this isnt in the case?

      --
      The One Rule Of Chess You'll Ever Need: Don't play someone who carries a kit in their bookbag.
    2. Re:Wrong way? by orangesquid · · Score: 2, Funny

      Yeah! Or, they might just have the photograph upside-down.... ;)

      --
      --TheOrangeSquid Is it any wonder things seem so awry? We swim in a sea of confusion and don't have to think to survive
    3. Re:Wrong way? by taion · · Score: 3, Insightful

      You should read the article more carefully before you comment next time.

      If you did, you'd clearly have noticed that the article said that the outer spiral arms pointed in the direction that they were rotating, and that was the peculiar aspect of this galaxy, not the actual direction of rotation itself.

      --

      ----------
      Floccinaucinihilipilification - the action or habit of judging something to be worthless
    4. Re:Wrong way? by ASCIIMan · · Score: 3, Insightful

      I think the oddity here is that it appears to be spinning counter to the direction its arms are swept, although its rotation could possibly be explained by a collision or combination with another galaxy.

    5. Re:Wrong way? by SpaceLifeForm · · Score: 2, Interesting

      I read the article carefully. My point was that it appears to be strange. If one galaxy is rotating clockwise (from our perspective), and another (either in front or behind but lined up with the first) is rotating counter-clockwise (from our perspective), and at the large distance involved, and the lack of accuracy in measuring such distances, there actually may be nothing strange going on at all. The spiral arms that appear to moving in the unexpected direction may actually belong to the other galaxy than the one that was apparently observed. The article infers that the two galaxies have collided, but they actually could just be close enough to each other to give the observed results. 111,000,000 lightyears is a long way away. I'll not go into gravitational lensing which can throw any galactic observation into doubt.

      --
      You are being MICROattacked, from various angles, in a SOFT manner.
    6. Re:Wrong way? by taion · · Score: 5, Informative

      You're continuing to misinterpret the article. The statement was that, for normal galaxies, the spiral arms trail the direction of rotation. That is, if the galaxy itself is rotating "clockwise", the spiral arms trail behind in a "counterclockwise" fashion.

      However, in this case, the spiral arms lead in FRONT of the galaxy's rotation. That is, if the galaxy is rotating "clockwise", the arms stretch forward in the "clockwise" direction; if the galaxy is rotating ccw, the arms also stretch forward ccw!

      The actual direction of rotation of the galaxy is irrelevant, the unexpected fact was the orientation of the spiral arms of the galaxy relative to the galaxy itself. Even in the event of an overlay, the rotation of the spiral arms in the unexpected direction could still be clearly observed.

      In your given case, with two galaxies possessing "normal" behaviour, the arms on both galaxies would trail in the direction of the rotation. If they were spinning in opposite directions, then which arm belonged to which galaxy would be entirely evident through the direction in which the spiral arms were rotating.

      Your objections, then, are entirely groundless.

      But I suppose we can just blame the editors for the vague title.

      --

      ----------
      Floccinaucinihilipilification - the action or habit of judging something to be worthless
    7. Re:Wrong way? by SpaceLifeForm · · Score: 0, Troll
      Me thinks you doth protest too much.

      I was not attempting to 'interpret' the article, just pointing out that the 'apparent observations' could have alternative interpretations.

      Want another? How about, lets speculate wildly here, that the arrow of time in that region has somehow reversed from 'normal' (our centric view) and that the processes the galaxy is apparently undergoing are actually happening in reverse!

      The point is, my 'objections' are not really objections, just 'alternative interpretations'.

      It does not matter whose interpretation is correct or not, we can never be sure anyway.

      It is a cool picture though!

      --
      You are being MICROattacked, from various angles, in a SOFT manner.
    8. Re:Wrong way? by kittenslietome · · Score: 4, Informative

      Here is a link to the guy's site--much more information and should be read before anybody starts making-up explanations.

    9. Re:Wrong way? by CheshireCatCO · · Score: 2, Informative

      There is a legitimate question here, and it's the subject of some tricky observing and analysis. You can get the Doppler map of the galaxy, by you need to work out which it is tipping towards you in order to work out if it is a leading or trailing arm spiral. It's hard to say if the "top" of the galaxy is nearer or us or the "bottom" is. If you can't tell that, you can't tell which way it is spinning.

      The usual way of guessing at this it to look for globular clusters. The side that is nearer us will have fewer gobulars in front of it than the farther side. But this is a guess, of course. With a nearly face-on galaxy, this difference is harder to pick out.

    10. Re:Wrong way? by panthro · · Score: 1

      I don't mean to nitpick, but I must point out that time is in no way fixed in direction or absolute (indeed, nothing is), and we perceive everything in our universe as a linear function of time from any given reference point. Therefore we can only see the end result of a distortion or reversal of time from our perspective, which implies that if time were "reversed" in a particular volume of space we would not see anything at all. Light emitted by the stars in the galaxy would by their own frame of reference be moving outward through this reversed space-time, but could not possibly coexist with light travelling subject to our frame of reference (as it would appear to be moving back to the source) and would therefore cease to exist or be trapped on the boundary and we would certainly never see it. To say nothing of many other inconsistencies, I think this is the simplest to understand.

      --
      If you're not part of the solution, you're part of the precipitate.
  2. CNN Article by Eigenray · · Score: 4, Informative

    CNN has an article with more information.

    1. Re:CNN Article by Telemakhos · · Score: 3, Insightful

      Someone should shoot the CNN editor who came up with the headline: "Goofy galaxy spins the wrong way"

    2. Re:CNN Article by ryusen · · Score: 1

      well we have a planet named "pluto" why not a galaxy named "goofy?" but then again... disney might start suing...

      --

      I believe sex is highly over rated... unless it involves me
  3. alright by nomadic · · Score: 4, Funny

    I think it's time we wrote our local congresspeople to get this remedied.

    1. Re:alright by dankjones · · Score: 1
      Yes, this is obviously a law enforcement issue, this galaxy needs to be imprisoned and reformed.

  4. ... by questionlp · · Score: 4, Funny

    That galaxy must be in the southern hemisphere of the universe?

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

      Assuming how it spins in northern hemispere is the "right" direction.???

  5. Spins wrong way by Anonymous Coward · · Score: 0

    Is this like the Simpsons episode where the water spins the wrong way in the toilet?

  6. Reverse Time by Anonymous Coward · · Score: 1, Interesting

    The flow of time in that part of the universe "backwards" to the flow of time in our part of the universe.

    1. Re:Reverse Time by PhuCknuT · · Score: 1

      If it was, would the galaxy be emiting light normally? I would think time flowing backwards would make very strange things happen optically. And what about the area in between, at what point do you leave "normal" time and enter "backwards time, and what heppens when you do? I would think it would be an impassible barrier to even light. Think about it, if light left normal space into space with backwards time, it would immediatly reverse direction wouldn't it? And as it came back into normal space it would reverse again. It would essentially be traped at the boundry. I can't think of a way that time could flow in a different directions in 2 parts of the universe without very strange easily observeable consequences.

    2. Re:Reverse Time by z)bandito(_X · · Score: 1

      your assuming that time is either forwards or backwards, yes or no, one or zero. what if the intermediate boundary was like a gradient? or analog as opposed to digital.

      just jabbering...

  7. Article in The Sun Newspaper Online by Anonymous Coward · · Score: 2, Informative

    The Sun Newspaper Online has a worth and informative article about this discovery in its Science section.

    1. Re:Article in The Sun Newspaper Online by Anonymous Coward · · Score: 0

      Hey, moderators!

      How about you follow the like before moderating.

  8. Is it that weird? by CheshireCatCO · · Score: 3, Informative

    I'm a bit confused at why anyone this that this is so bizzaire. Sure, most galaxies are trailing spirals, but there are enough leading spirals to make them not freakish. I'd suspect that it is the spin put on the story by the media, but one astronomer is quoted calling leading-arm spirals extremely rare.

    My take on this is that the real news is the evidence of disruption/interaction. We've seen that before (M51, the Whirlpool, is a good example), but it's still a damned cool thing to see.

  9. More math is needed by Daniel+Dvorkin · · Score: 3, Informative

    Says the math geek, I think this is as much of a mathematical problem as an astronomical one -- i.e., we really don't have a good grasp of the dynamics of galaxy formation, and we won't until the math is there. Classical Newtonian orbital mechanics doesn't do it, of course, since it's an n-body problem with a very, very large value of n. Some new kind of analytical technique needs to be invented before we can say we know much about why galaxies look and move the way they do.

    --
    The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
    1. Re:More math is needed by CheshireCatCO · · Score: 2, Interesting

      The 3-Body problem cannot, in general, be tackle analytically (Poincare showed this). So I am hesitant to believe that we will ever have an analtical technique to directly handle a billion-body problem, like galaxies.

      That said, we *do* have analtic techniques to examine galactic dynamics. Lots of 'em, ranging from fluid discriptions to wave approximations. But stunning coinidence, I was just reading Binney and Tremaine, a whole text on galactic dynamics. (The physics is pretty much the same as in planetary rings.) So lots of math exists to tackle these problems. As a math major in astro. grad school, I am pretty confident when I say that the mathematicians won't need to cook up new tools as much as we need to figure out how to apply the existing ones.

      The other approach is, of course, various simulation techniques, mainly N-body codes. For that we need
      a) Faster computers. We always want faster computers.
      b) Better algorithms. This is a place with the Applied Math folks would be really helpful.

    2. Re:More math is needed by alfredw · · Score: 2

      What we really need is more data. Various examinations of the winding problem have been made, and most reasonable solutions lead to very tightly wound spiral arms, if there are any at all. We don't see this, though. We now have this galaxy with arms "trailing" in the same direction as its motion...

      Hopefully we'll be able to take this and turn it into a more accurate model of what a galaxy IS so that we can then figure out why it DOES what it does.

      --
      In Soviet Russia, sig types you!
    3. Re:More math is needed by CheshireCatCO · · Score: 1

      We have data: lots of pictures of pretty spiral galaxies. You yourself point out the problem: we can't explain those data.

      Shameless plug for my own work: maybe Saturn's rings will provide a suffient analog to further our understanding. Cassini arrives in 2 years for some up-close views of what's happening.

  10. How do we know? by Phosphor3k · · Score: 1

    Maybe that Galaxy is standing still, or spinning very slowly, and we are spinning the wrong way?

  11. upside down? by rhdfhfdhfh · · Score: 1

    Maybe they're looking at it upside down? :)

  12. that's easy! by Anonymous Coward · · Score: 0

    ever been to australia? their toilets spin the wrong way- that must be on the underside of the universe!

    /me goes out and mugs steven hawkings and steals his phd.

  13. What this shows.... by Anonymous Coward · · Score: 1, Interesting

    is that there is more to a galaxy than what we can see, i.e. dark matter. Have you noticed that the time it takes the outside of the galaxy to orbit the core is the same as the inside? Normal physics, assuming what's lit is what we can see, would say that the outside would have to orbit much, much slower to not overpower the galaxy's gravity. But they don't, meaning some other source of mass must be both moving with the arms to keep them up, and providng the gravity necessary to keep them in. Otherwise, the core would rotate very quickly, and you would get what happens when you swirl chocolate milk mix in with milk, it'd blend. Not only does that not happen, but there are barrel-arm galaxies whose arms stick straight out, and now, galaxies whose arms point the direction they're going.

    I think this just shows even more convincing evidence for dark matter. By exemplifying this galaxy, we can show that there has to be something else there preventing the arms from "oozing" behind the rotation of the galaxy.

    Chocolate milk: explains all, even mysteries of the universe

    1. Re:What this shows.... by CheshireCatCO · · Score: 3, Informative

      You're right up until you state that the core must rotate more quickly. Dark matter has nothing to do with the core of the galaxy or its rotation. And even if the core did rotate rapidly, a la stars about a black hole, so what? There wouldn't be any radial mixing from that, as long as the orbits were Keplerian and nearly circular (which they are, as far as I've heard).

      I also fail to see why this result indicates the presence of dark matter. The direction of rotation should not depend on the dark matter content. This is about how the galaxy formed and how the spiral arms were generated, not about what the galaxy is made of.

    2. Re:What this shows.... by z)bandito(_X · · Score: 1

      wouldn't what its made of affect how its created?

    3. Re:What this shows.... by Jaysyn · · Score: 1

      hmmmm.....Dark Matter...God's invisable paper-mache'.

      Jaysyn

      --
      There is a war going on for your mind.
  14. Time by sean23007 · · Score: 2, Interesting

    Maybe they made a mistake in the measurements, and as they graphed the rotation of the galaxy time was actually going backwards in their simulation. That would yield the results we see now, in a much more humorous (in a slap-yourself-in-the-face kind of) way.

    --

    Lack of eloquence does not denote lack of intelligence, though they often coincide.
  15. New Scientist Retraction by falser · · Score: 1

    They just realized that they were looking at the photographs upside down :)

    1. Re:New Scientist Retraction by CTalkobt · · Score: 1

      Actually, if would be more accurate to say that they were looking out from the piece of paper that held the photograph to get the images they were seeing.

      An upside down spiral is still a same arm direction spiral.

      --
      There's a gorilla from Manilla whose a fella that stinks of vanilla and has salmonella.
  16. Bizarro Galaxy! by Halloween+Jack · · Score: 2, Funny

    It am Bizarro Galaxy. Everything am different in Bizarro Galaxy. For example, me am happy in job and relationship; am handsome, too.

    --
    I looked into the abyss, and the abyss looked into me--and we both winked.
  17. antimatter by gCGBD · · Score: 1

    So this is where antimatter comes from...

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    O=='=++
  18. CCW - my ass. by http101 · · Score: 0

    Yeah, so the Big Bang threw out all these Gazillions of galaxies and don't ya'll think it might be a slight bit possible this one did a 180 degree flip? It's more than likely a slow week in the news, so of course, as always, we have to make up some interesting BS that befuddles unintellectual types. Way to go guys, I'm glad to see we passed geometry class. Get a life you dumbass reporters...

    --
    -- Game Developers: Stop porting badly-textured games from crappy console systems!
  19. Junk food for thought by Merovign · · Score: 1

    For about two seconds, I thought:

    "Ooooh! Ooooh! Maybe someone engineered that as visible proof of their presence!"

    Then I thought:

    "But that would only be a slight probability if it was the only one,"

    And it wasn't. And then I thought:

    "what if several civilizations had the same idea at the same time?"

    Could you imagine how pissed you'd be if you went to all that trouble to stand out and two guys down the block did the same thing? :)

    Idle thinking, like idling at a stoplight, burns fuel and gets you no-where. But then again, stopping and starting at every stoplight wastes even more fuel and puts more wear on the engine so... I wonder where I was going with that?