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The Universe Within 12.5 Light Years

(www.atlasoftheuniverse.com)
266 points algorithmista | 2 comments | 05 Sep 25 22:20 UTC | HN request time: 0s | source
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arkaic ◴[06 Sep 25 02:14 UTC] No.45145988[source]▶
For getting the feel of the milky way, I think there's nothing that is better able to simulate it than a video game, ala Elite Dangerous. I loved to navigate its galaxy map. The size of the Milky Way, the numbers of stars and distances between them are of scale in there if I recall correctly.
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1. codesnik ◴[06 Sep 25 12:32 UTC] No.45148725[source]▶
I recently contemplated about a thing: on a galaxy scale, the speed of gravity (or gravity change) should have a somewhat noticeable effect. There's a slight pull towards a star on the other side which is not there anymore for 50000 years! Of course there's some other star in that place, but I wonder how minuscule that effect is. Would it speed up or slow down rotation of outer regions of galaxy?
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2. baq ◴[06 Sep 25 13:48 UTC] No.45149243[source]▶
Gravity works the same as light - if you see it somewhere, it pulls you in that direction. The fact that it’s somewhere else now is irrelevant, because the now is tightly coupled to the where thanks to relativity.