how can we see billions of light years away?

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Like surley it would take billions of light years to receive the images? How else could we see everything else in the universe?

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Anonymous 0 Comments

>Like surley it would take billions of light years to receive the images?

You bet! When we get an image of a star or whatever that is 1 billion light years away, we are receiving photons emitted 1 billion years ago, and we are getting a picture of what it looked like 1 billion years ago. We have _no idea_ what it actually looks like today because the photos emitted today aren’t going to arrive for another billion years. Every picture we have of anything in space is a picture from the distant past.

>How else could we see everything else in the universe?

We can’t! We can only see things that where the light has had enough time to reach us. There is an edge to the observable universe, where the universe simply isn’t old enough for the light to have had time to reach us. We have _no idea_ what is beyond the edge of the observable universe.

Anonymous 0 Comments

Our sight does not “see” any distance whatsoever. Anything we see is because the the light has come to our eyes. Same applies to cameras.

In other words, our eyes are severely limited as to what they see because they rely on light either being emitted by a distant object or light being reflected off a distant object and arriving at at our eyeballs.

We don’t see “away”. The “away” comes to us.

We definitely can NOT see everything else in the universe. There is an unknown amount of the universe that we will never see because of the expansion of the universe being faster than the speed of light in some areas. In the far future, less of the universe will be visible due to expansion. We are lucky that we can see as much as we can.

Anonymous 0 Comments

Yep! It has! The universe is about 13 to 14 billion years old and the oldest light we can see is only a little bit younger! That means that that light has been travelling to us almost as long as the universe has existed!