If we are at point A in the universe and something is say 13 billion light years away, wouldn’t we have to travel wayyyy faster than the speed of light from the Big Bang in order to turn around from point A and “look back in time” that far? I don’t know if I’m making any sense here, but how did we get “here”, 13 billion years before even the light from those galaxies got here?
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$\begingroup$ I guess you are asking this question inspired from"How JWST could see 13 billion years back in time" $\endgroup$– Kavin IshwaranCommented Jan 22, 2022 at 4:02
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1$\begingroup$ Does this answer your question? astronomy.stackexchange.com/questions/6397/… $\endgroup$– Dave GremlinCommented Jan 22, 2022 at 7:53
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3$\begingroup$ Your question has a different title, but its the same as the one about the centre of the universe. You assume the "big bang" was an explosion that happened at one place (the centre) and we travelled away from it. That's not correct. The big bang happened everywhere. $\endgroup$– James KCommented Jan 22, 2022 at 8:02
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$\begingroup$ Also astronomy.stackexchange.com/questions/874/… You've actually asked the same question before. astronomy.stackexchange.com/questions/25710/… $\endgroup$– James KCommented Jan 22, 2022 at 8:03
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1 Answer
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Thirteen billion years ago, the universe was already much larger than 13 billion light years across. It may in fact be infinite.
At that point, our galaxy may not have existed (I'm not sure), but the hydrogen that is now in it did exist. Let's pick one such hydrogen atom for reference. At that point in time, light left a galaxy that was 13 billion light-years from our reference hydrogen atom. Over the following 13 billion years, our galaxy and then our solar system formed. Meanwhile, the light from the other early galaxy was approaching us, and the galaxy the light came from was getting farther away. Finally, this year, the light is reaching us. Meanwhile, by now, that galaxy is even farther away from us.
