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mjtolsma
2008-Apr-22, 08:36 PM
I would like to post the following question. I'm not a physicist, so forgive any grave errors :)

We can see light from billions of lightyears away. It is possible to look at a moment in which the galaxy was very young.
However, it is a scene which we view billions of years later. How can we view this? You would think that the light would have "past" us by now.

Can this be explained by the relativity-theory?
Kind regards, Martijn

dcl
2008-Apr-22, 09:21 PM
The following responds to mjtolsma.

Light comes to us continuously from any given distant object in the universe. We see that object only by light that is arriving from that object at the present instant. Ten minutes from now, we'll see that object by light that left it ten minutes later than did the light by which we saw it ten minutes ago. The time between when light left the object and when we see it depends on how long it takes the light to pass from the object to us,.