Eli5 When we look at a star 10 LY away, are we seeing 10 LY away or are we just seeing the light when it reaches us, or is it a mix?

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Title pretty much covers the question.

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Anonymous 0 Comments

We’re seeing the light as it reaches us, and it’s been travelling for 10 years from our perspective.

Fun fact; given the expansion of the universe, by the time we see the light that came from 10LY away, the actual distance to the star now is more than 10LY (not by much, but the further you go, the more pronounced the effect).

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