Diameter of Universe
Name: Thomas P.
What is the diameter of the Universe?
This is a tricky question to answer because the term "diameter" implies that there is
"something" on the "other side", but there is no "other side" so when an astronomer
observes a more distant object (s)he is looking back in time rather more than in space,
actually space-time. The further an object appears, it actually means the older it is.
Recent observations suggest that the expansion of the Universe, in which everything is
receding from every other thing, is actually accelerating. The Universe expansion does
not appear to be slowing down! Sound confusing? It is. It is difficult but inescapable --
how the Universe is behaving is not well understood.
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Update: June 2012