Spiral Galaxy Spins the Wrong Way 51
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."
Wrong way? (Score:2, Interesting)
Space can be tricky, there is more there than meets the eye.
Re:Wrong way? (Score:2, Funny)
Re:Wrong way? (Score:3, Insightful)
Re:Wrong way? (Score:3, Insightful)
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.
Re:Wrong way? (Score:2, Interesting)
Re:Wrong way? (Score:5, Informative)
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.
Re:Wrong way? (Score:1)
Re:Wrong way? (Score:2, Informative)
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.
Re:Wrong way? (Score:4, Informative)
CNN Article (Score:4, Informative)
Re:CNN Article (Score:3, Insightful)
Re:CNN Article (Score:1)
alright (Score:4, Funny)
Re:alright (Score:1)
... (Score:4, Funny)
Reverse Time (Score:1, Interesting)
Re:Reverse Time (Score:1)
Re:Reverse Time (Score:1)
just jabbering...
Article in The Sun Newspaper Online (Score:2, Informative)
Is it that weird? (Score:3, Informative)
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.
More math is needed (Score:3, Informative)
Re:More math is needed (Score:2, Interesting)
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.
Re:More math is needed (Score:2)
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.
Re:More math is needed (Score:1)
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.
How do we know? (Score:1)
upside down? (Score:1)
What this shows.... (Score:1, Interesting)
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
Re:What this shows.... (Score:3, Informative)
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.
Re:What this shows.... (Score:1)
Re:What this shows.... (Score:1)
Jaysyn
Time (Score:2, Interesting)
New Scientist Retraction (Score:1)
Re:New Scientist Retraction (Score:1)
An upside down spiral is still a same arm direction spiral.
Bizarro Galaxy! (Score:2, Funny)
antimatter (Score:1)
Junk food for thought (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?