Photo of the entire Universe

[car]

Originally posted by arian_ma
Something cool for ya'll to think about.

It is estimated that our universe is 13.7 billion years old.
It is also estimated that our universe is 156 billion light years across.

If the speed of light is the fastest speed anything can travel at, how did matter travel 78 billion light years in just 13.7 billion years?

Ahha, finally, something I ACTUALLY did learn in class.
Yes, nothing can travel within the fabric of space faster than the speed of light. But the universe can expand faster than the speed of light. Imagine the lines on your graphing paper expanding, the relative speed of the lines going away from each other is faster than the speed of light, but nothing is TRAVELLING on the paper faster than speed of light.

[car]

...and its because of this phenomenon that eventually we will no longer be able to see stars outside our local cluster, the space between us is expanding faster than light can travel.

sad

[freshprince1]

Originally posted by msommers
I'm probably not understanding it fully, but wouldn't it take millions of years for light to reach the scanner to even recognize that something is there?

That's true. And as mentioned, the light has already been travelling for that amount of time to just get here. So what that means is that what we see in space (depending on how far we are looking) we are looking into the past. So we could be looking at stars that have already supernova'd, but we don't know that yet because that has yet to reach us. Make sense?

[msommers]

Ya thanks man. It makes sense from a mathematical standpoint, in practice the idea of looking back in time essentially is just fuckin weird.