Suppose that someone in the Andromeda galaxy had a super-telescope through which they were looking at Earth right now. They would see Earth.
Added by Ivan S.
Step 1
The Andromeda galaxy is approximately 2.5 million light-years away from Earth. This means that the light from Earth that is currently reaching the Andromeda galaxy left Earth 2.5 million years ago. If someone in the Andromeda galaxy had a super-telescope through Show more…
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