How did we get 13.2 billion light years from the faraway galaxies being discovered with Hubble?

If we all started near each other at the Big Bang, and we all travelled slower than the speed of light, and the universe is about 13.9 billion years old, how could we possibly be 13.2 billion light years away from recently discovered galaxies?

I know "inflation" was supposedly superluminal, but I bet no one thinks that matter dispersed several billion light years apart during that operation.

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    $\begingroup$ Not only are objects such as galaxies moving in space, but space itself expanded. At the Big Bang, or as close to it as can be modelled, everything was incredibly close together. And by everything I mean space, time and energy - all compressed. Since then, energy condensed to mass, eventually leading to galaxies, and space has continued to expand. Your final sentence is the bit you have wrong - galaxies could easily travel slower than light, and still now be farther apart than the speed of light would allow, because space itself has moved farther apart. $\endgroup$
    – Rory Alsop
    Aug 12, 2015 at 6:50
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    $\begingroup$ I voted you up cause I don't think it's a bad question, though it's perhaps poorly researched. There's no shortage of explanations on the expanding universe available to a quick Google search. Here's a rather simple video on the subject: youtube.com/watch?v=th_9ZR2I0_w There's also, no reason that the big bang couldn't send 2 galaxies 13.2 billion light years apart in 13.9 billion years cause that's less than the speed of light. The mind bender is that those galaxies that we see 13.2 billion light years away are now about 44 billion light years away. :-) True story. $\endgroup$
    – userLTK
    Aug 12, 2015 at 7:00
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    $\begingroup$ @userLTK: Why don't you make this an answer? I agree that it's a good question. It may be poorly researched, but this may be difficult if you have no idea where to start. If the question doesn't get an answer (the one already given does not answer), then I suppose it should be closed. $\endgroup$
    – pela
    Aug 12, 2015 at 7:47
  • $\begingroup$ The Big Bang did not happen at a point. $\endgroup$
    – HDE 226868
    Aug 15, 2015 at 23:58

2 Answers 2


The distance you are referring to is the "light travel distance". It is the length of time that light has been travelling from the distant galaxy to us.

When the light was emitted, our Galaxy was much closer to that distant galaxy. What has happened in the meantime is that the space between the galaxies has expanded.

Furthermore we can ask where is that galaxy right now (where now is a time measure since the big bang) and it turns out that the galaxy would be much further away than 13.2 billion light years - more like 40 billion light years if you were to somehow measure that distance with a very long ruler.


Don't think of inflation as super luminal movement of our galaxy from others. Think about the 'stuff' that makes space-time between the galaxies simply increasing (this is inflation). This causes the light to travel through more and more 'stuff' as time is passing by.

Imagine a clump of space-time A, and another B, next to each other at the start of the Big Bang. Then add some more clumps of space-time between them. You wouldn't think that the objects within space-time A and B have actually moved. A really basic analogy would be two pool balls next to each other with an ant on each. The ants can only travel to the next ball by walking on the the balls (ignore the ground). Then imagine the same scenario, but you add another ball between them. The ants haven't moved on the balls, but they would have to travel further now to get to the ball the other ant is on. The balls in the example would represent space-time, and the ants any galaxy/star.


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