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Fascinating. A related question: When we look at Andromeda, which has a diameter of 220,000 light years, we are looking at it slightly edge on. Shouldn't the st
by waynecochran 3y ago
Fascinating. A related question: When we look at Andromeda, which has a diameter of 220,000 light years, we are looking at it slightly edge on. Shouldn't the stars on the back edge be in a relatively different place in the sky than the stars on the front edge since the galaxy has moved relative to us over that 220K light years?
- Filligree 3y agoYes. And, of course, they are.
- waynecochran 3y agoThey appear as if I am looking at the front and back edge at the same point in time -- i.e. not 220K years apart.
- hughes 3y agoHow would you expect it to look that is different from its current appearance?
- tekla 3y ago/gif head exploding meme
- waynecochran 3y agoI would expect something kind of stretched out and warped like taffy. i.e. the front edge of the galaxy would be stretch out ahead of the back edge of the galaxy since the back edge is running behind time-wise.
- ahazred8ta 3y ago> stretched out ahead You have apparently not figured out (1) by how much? and (2) in which direction? - Andromeda rotates so slowly that after 220K years the far side has made only 1/1000th of a rotation. Please draw on a picture of Andromeda how far the far side moves after 1/1000th of a rotation. That's how small the image warping is.
- waynecochran 3y agoThank you. The "how much" is too small to stretch it out visually. Need a much larger spiral galaxy to see the effect I am thinking of.
- Filligree 3y agoA larger galaxy would rotate even slower. I don’t think this is a game you can win.
- mrguyorama 3y agoNever forget that the universe does not have a "preferred scale" and has fractal complexity and emergent behavior from the smallest two particle interactions to the largest black holes circling each other. Our 10 pound hunk of fat is not able to comprehend that.