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Astronomy

Why Comet Tails Always Point Away from the Sun

Quick fact

A comet's tail can be millions of kilometers long, and it always points away from the Sun, no matter which direction the comet is moving.

Why this is interesting

Ever seen a comet with a tail pointing away from the Sun? It's not trailing behind like a fluffy dog's tail—it's always pointing outward. Why does it behave so contrary to what you'd expect?