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World 5 · The Missing Mass: Dark Matter · 13 min · PRO

What could it be? And what we don't know

The evidence is strong, the identity is open

PRO · Cosmos: Big Bang to Now

World 5: The Missing Mass: Dark Matter is part of PRO

The first world of Cosmos: Big Bang to Now is free. PRO opens the other 25 lessons in 6 worlds — simulations, quizzes and all.

  • Orbits in a galaxy: how Kepler predicts the speeds
  • Rubin's flat curves
  • More evidence: clusters, lensing and the Bullet
  • Galaxies are not alone: groups and clusters
  • Tidal tails and mergers
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← More evidence: clusters, lensing and the BulletGalaxies are not alone: groups and clusters →

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