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James Webb Space Telescope reveals that most galaxies rotate clockwise

smithsonianmag.com

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Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#111

Post by tomr_stargazer »

like_any_other wrote: post #19

> Due to an effect called the Doppler shift, astronomers expect galaxies rotating opposite to the Milky Way’s motion to appear brighter How does this work? The page it links to doesn't explain why rotation would matter. Edit: To clarify - one side of the galaxy would be moving towards us, and one away from us, no matter which direction it spins in, so this should not affect the average brightness of the entire galaxy…

I think this may be a subtle reference to what is usually called "relativistic beaming" or "Doppler beaming" [0], though I normally associate this effect with matter that is moving quite close to the speed of light.

[0]: https://en.wikipedia.org/wiki/Relativistic_beaming

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#112

Post by mapt »

Fascinating.

Did it require JWST to notice this, or did we just _not check_ until now?

Is there a notable asymmetry in, say, the spin directions of galaxies contained in the Hubble XDF?

EDIT:

This doesn't make a lot of sense. Lior Shamir has written that a lot of unrelated sky surveys recently have shown an asymmetry in the past few years, but only down around ~2%.

https://www.mdpi.com/2073-8994/16/10/1389

https://aas.org/sites/default/files/2020-05/lior_aas236.pdf

JWST's asymmetry in both early work and more recent deep fields is more than an order of magnitude stronger.

EDIT2: Notably they show anisotropic asymmetry: The galaxies are different rotations when you look in different directions, with something like +6% in one direction and -5% in another. But still nothing like the +50% now being reported as a general feature.

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#113

Post by Ygg2 »

over_bridge wrote: post #35

Seems like we've got a few of these imbalances now where you'd expect 50:50 but instead it's skewed to one side where nature had a different idea Matter-antimatter ratio Left vs right handed molecules Now galaxy spin directions Maybe there are others I missed too

> Left vs right handed molecules

Organic chemistry found on meteors shows that non-terrestrial sources are equally left vs right-handed.

However, the rest might be caused by one or more errors in our premise. The most likely culprit being cosmological principle.

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#114

Post by perihelions »

tomrod wrote: post #110
perihelions wrote: post #18

Earlier quoted context omitted.

I don't understand how the 1e-16 Hz rotation of the Milky Way affects how we perceive other spiral galaxies' orientations.

Relative motion to the center. 230 km/s is fast.

Then how does linear motion do it?

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#115

Post by stainablesteel »

so i guess the underlying assumption is that this looks out from out perspective in a single static orientation, because this says nothing to me about their orientation which i think is what they're trying to convey by saying clockwise?

or i suppose this is clockwise/counterclockwise in regards to the direction they're moving in?

2/3 doesn't seem that significant if they think it should be a 50/50 split, we might just not be seeing enough

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#116

Post by stainablesteel »

over_bridge wrote: post #35

Seems like we've got a few of these imbalances now where you'd expect 50:50 but instead it's skewed to one side where nature had a different idea Matter-antimatter ratio Left vs right handed molecules Now galaxy spin directions Maybe there are others I missed too

there's also that famous experiment by Chien-Shiung Wu, veritasium did a video on it somewhere

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#117

Post by lupusreal »

askonomm wrote: post #85
thunder-blue-3 wrote: post #75

Earlier quoted context omitted.

I've been following this news for the past couple of weeks-- in essence your statement is what they are hypothesizing, and that the "something at the center that unites the two poles" might be that we are within a black hole. https://en.wikipedia.org/wiki/Black_hole_cosmology for the curious.

It was my understanding that if two black holes collide, they just form a bigger black hole, but we know there's a black hole in our universe, which then would mean that there's a black hole inside of a black hole that did not merge with the parent black hole, right? Is that something that is considered possible?

I'm under the impression that we really have no clue what's going on inside of black holes, so the most we can really say with confidence is that when two black holes collide they appear from the outside to now be a single black hole.

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#118

Post by lupusreal »

Is this a robust finding? I heard something about this apparent discrepancy a week or so ago, and it was dismissed as probably just an artifact of dodgy classification and the paper's author was a bit of a kook, a computer scientist who was delving into cosmology to find evidence of the simulation hypothesis.

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#119

Post by wruza »

floatrock wrote: post #82
Patient0 wrote: post #70

Earlier quoted context omitted.

The actual paper makes more sense: "the number of galaxies in that field that rotate in the opposite direction relative to the Milky Way galaxy is ∼50 per cent higher than the number of galaxies that rotate in the same direction relative to the Milky Way."

So 1/3 MilkyWay-Wise, 2/3 Counter-MWW? Or is it? I hate these percent-relative word games things... - Let x = "num MWW" - then "num CMWW" = 1.5x ("50% higher than x") - x + 1.5x = 1 - x = 0.4 So 40% is MWW, 60% CMMW?

Correct, I guess. 40/100 x 1.5 = 60/100. For 1/3 and 2/3 it must have been 100% higher.

Re: James Webb Space Telescope reveals that most galaxies rotate clockwise

#120

Post by worldsayshi »

deepsun wrote: post #60
worldsayshi wrote: post #42

Earlier quoted context omitted.

> relative to our viewpoint That would seem way more surprising than relative to a arbitrarily selected common upwards direction and it would imply that we are somehow at the center/top of the universe.

You are correct, we are indeed at the center of the universe. Hence the farther we observe stuff, the earlier in time it happens. And if an observer moves to a different location, they will still be at the center of the universe (aka light cone).

> And if an observer moves to a different location, they will still be at the center of the universe (aka light cone).

That doesn't make sense for this particular context though. The direction of "up" of another galaxy doesn't change depending on where you are as an observer...

Then again, it's only two-thirds of the galaxies that have "up" facing us - which isn't that surprising. If something like 99% of their "up" was facing us it would seem more special.

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