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Due to the scale of the universe, when we observe a star in the night sky, we are seeing it?

Answer 1

All stars we see with the naked eye are within our Milky Way. We cannot see stars from other galaxies, and we are seeing the light it emitted many years ago.

As light takes 30 years to travel from a star to Earth, when you observe a star that is 30 light years away, you are seeing the star as it was thirty years ago, not as it is now.

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Answer 2

Luca de

We are seeing the star as it appeared in the past, due to the finite speed of light and the vast distances involved in interstellar space.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.