Follow your curiosity

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FACTREE gives you something interesting to discover every day — and something worth talking about together.

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Astronomy

Cosmic Expansion

Quick fact

The expansion of the universe is not like an explosion sending galaxies outward through space; rather, space itself is stretching, carrying galaxies along as if they were dots on an inflating balloon.

Why this is interesting

You look up at the stars and they seem fixed in place, yet every distant galaxy is racing away from us. Why is the entire universe stretching like a rubber band?