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

Dark Matter

Quick fact

Dark matter accounts for roughly 85% of all matter in the universe, but we have never directly detected it.

Why this is interesting

You know those graceful spiral galaxies like the Milky Way? Their outer stars orbit way too fast – as if some invisible mass is holding them together. What could it be?