Astronomers explain.I am confused, if the universe is expanding faster than the

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Aqua99

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speed of light, but then also ? Okay, faster than the speed of light, but also the sun used to be closer in to the center of the universe(so to speak, as the universe expands) why can't we intersect, or see old light from our sun? (see back in time,kinda) It's hard to visualize all the different motions involved,and light paths, to make it easier.
 
The Universe isn't expanding faster than light speed. However..... The most distant objects we can see are traveling away from us at relativistic speeds great enough that the light from them is red-shifted far down into the microwave (and longer) wavelengths. This does put an ultimate limit on how far we can 'see' into the Universe. In fact, what is called 'background radiation' is simply the remnants of the Big Bang.
As the Universe expands everything in it moves (generally) away from everything else. The example I always used was raisins in a cake as it bakes. All of them move apart from one another so that each raisin 'sees' all of the others receding. But note that there is also a lot of 'swirling' type(s) of motion taking place in the Universe as well. It is for this reason that galaxies can sometimes collide.

Doug
 
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