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How to Describe the Image of a Star Which is 10 Light Years Away

-- | December 13, 2018

Question: When I see a star that is, let’s say, 10 light years away; can I say that what I’ve seen is the image of that star 10 light years ago? — Joseph

Answer: Better to say that you have seen that star as it was 10 years ago, since a “light year” is a measure of distance, not time.

Jeff Mangum

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