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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

#81

Post by like_any_other »

IsTom wrote: post #74
perihelions wrote: post #34

Earlier quoted context omitted.

- "Doppler shift, astronomers expect galaxies rotating opposite to the Milky Way’s motion to appear brighter" But how does that work?

I would assume that they're talking about redshift.

Yes, but one half of a galaxy would get redshifted, and the other blueshifted, no matter which direction it spins in. So why would that change its overall brightness?

(Though one of the papers notes that the tiny change in brightness this causes isn't enough to explain the large difference in spin directions)

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

#82

Post by floatrock »

Patient0 wrote: post #70
vincnetas wrote: post #67

But rotation direction depends on the observer. If i see galaxy spinning clockwise, this means someone observing galaxy from behind it sees it rotating counter clockwise. So are we just located so in the universe that we see 2/3 spinning clockwise and another counter?

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?

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

#83

Post by Reubachi »

permo-w wrote: post #63
keyle wrote: post #9

Potentially a very dumb question, but seeing the difference between cyclones and hurricane on earth (clock-wise, anti-clock-wise)... Does it mean that we are, potentially, on one of two poles(?) of the observable universe, if we're observing most galaxies around us rotating a certain way?

maybe this is a stupid question, but is it possible that the big bang simply had some kind of clockwise angular momentum to it? how different is that idea from the black hole cosmology concept? I don't really understand how the two fit together

I don't believe the current consensus is that motion from big bang imparted a spin on objects. Rather, that dark matter (mass) was "dropped" all over as a result of the bang, making gravitational hot spots. Millions of years of dark energy progression affects those hotspots, making a sort of ever expanding (yet perceptively slowing down) sink drain with water pouring into it.

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

#84

Post by jncfhnb »

permo-w wrote: post #79
vincnetas wrote: post #67

But rotation direction depends on the observer. If i see galaxy spinning clockwise, this means someone observing galaxy from behind it sees it rotating counter clockwise. So are we just located so in the universe that we see 2/3 spinning clockwise and another counter?

this is a hard one for me to instinctively understand spatially, so I’m imagining myself stood in a room with arrows pointing left and right. if I have 3 arrows facing left in front of me and behind me I have 3 arrows facing left -- from my perspective when I turn around -- then I step past one of the arrows and now I have 2 left facing on one side and then in front of me what was now a left arrow is a right arrow, s…

No I don’t think so

Once you have a few dimensions on a normal or other distribution there’s not a lot of content that’s in the middle.

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

#85

Post by askonomm »

thunder-blue-3 wrote: post #75
fennecfoxy wrote: post #59

Earlier quoted context omitted.

That would be super cool to find out! And then it also begs the question, is there something at the center that unites the two poles? If so then what is it! It would also imply that our whole universe is rotating - the only reason this happens on Earth is because of our planets rotation and the Coriolis effect.

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?

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

#86

Post by BubbleRings »

I was disappointed that the article only once mentioned “from our perspective” in relation to the spin of galaxies. One of the most fascinating things that you first learn about when you try to understand relativity, is the fact that there is no “still” point in the entire universe. Out in space, the point in space one foot in front of your space suit’s helmet can be called still by you, but it is just as reasonable to call a rock racing by you at a million miles an hour the central still point, where all other motion in the universe can be measured against. Because there is no absolute still anywhere. And when you understand that, that’s when all these cool concepts can then be described, related to time changes that happen between two locations when the relative speed difference between the two objects or locations approaches the speed of light. (So you can return from your trip to Alpha Centuri and meet your great great grandson who is older than you.)

And just like there is no still point in the universe, there is no up or down. So yes, it may be true that, IF you select a couple of arbitrary points in the universe to be up and down, THEN you can count how any galaxies spin left vs right. And it is way cool to find out that it doesn’t appear to be 50/50, and to wonder about why. But I think the article author did the readers a disservice by glossing over the “no up or down” fact.

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

#89

Post by layer8 »

damnitbuilds wrote: post #51

1. Are they really saying "Because we are in a universe with a preferred spin and black holes have spin, we must be inside a black hole?" Tenuous, no? 2. If we are inside a black hole, where is the singularity?

Inside a black hole just means inside its event horizon. The singularity can still be arbitrarily far away from that horizon (if the black hole is correspondingly large). The volume enclosed by the event horizon may be larger than our cosmological horizon (i.e. how far the speed of light allows us to see, given the finite age of the universe.) And the singularity of a black hole isn’t “where”, it’s “when”. The singularity of a black hole is in the future of all particle trajectories inside the event horizon.

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

#90

Post by alfiedotwtf »

Gooblebrai wrote: post #52
keyle wrote: post #9

Potentially a very dumb question, but seeing the difference between cyclones and hurricane on earth (clock-wise, anti-clock-wise)... Does it mean that we are, potentially, on one of two poles(?) of the observable universe, if we're observing most galaxies around us rotating a certain way?

Regardless of if this is the case, the idea certainly blew my mind

lol, I’m glad it wasn’t just me that thought “woah wait. wtf did you just say??!”
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