#astronomy
3 article(s)
How Big Is the Universe, Really?
The numbers are so large they stop meaning anything. So let's build up to them one impossible step at a time.
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What Is a Light-Year — and Why You're Seeing the Past Right Now
A light-year isn't a measure of time, and the night sky isn't a live picture. Every star you see is a message from history.
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Why Is the Night Sky Dark? The Puzzle Called Olbers' Paradox
It sounds like a silly question with an obvious answer. It isn't — and taking it seriously helped reveal the nature of the entire universe.
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