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[–] PraiseIPU 0 points 0 points (+0|-0) ago 

So earth is 4.5 bilkion years.

Something intelligent evolved on earth in the first billion years and sent out a signal.

They are just returning our call.

[–] B3bomber 0 points 0 points (+0|-0) ago 

This would be a 6 billion year round trip response time. This solar system formed from a star nearby going supernova (about 4.5 billion years ago). Likely they were replying to them.

[–] PraiseIPU 0 points 0 points (+0|-0) ago 

dammmit now I'm thinking about the expansion of the universe and how that effects the signal time.

is the signal currently 3 billion years away. or was it 3 billion years away when it was sent?

so the universe has expanded 3 billion light years in that time. so roll it back. was that galaxy 3 billion years closer then?