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Do We See Multiple Versions of a Star When Looking Back Through Spacetime?

-- Chuck | April 15, 2021

Artist impression of a galaxy during the Epoch of Reionization

Question:

Do we see multiple versions of the same star when looking back through spacetime? Let’s say our star, Bob, was born in depression-era 1930s… Do we only see Bob as an infant, or do we see Bob in primary school, on his wedding day, or even the final day when he passes to the next plane (supernova)?

-- Chuck

Answer:

No. When we look at an object in the universe we see that object as it existed when the light we observe from it was emitted. Since the speed of light is finite, it takes some time for that light to reach us, dependent upon how far away the object is. We therefore can only see what an object looked like at a given point in the past.

-- Jeff Mangum

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