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Dark matter: How does it explain a star's speed? - Don Lincoln

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The physics of the universe

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All the stars in a spiral galaxy rotate around a center -- but to astronomers, the speed that each star travels wasn't making sense. Why didn't stars slow down toward the edges as expected? Don Lincoln explains how a mysterious force called dark matter is (possibly) the answer -- and why the search for an answer matters.

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The fact that we can see so many spiral galaxies using our telescopes tells us that they are both ____.
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Space Ed helps you untangle the mysteries of space with the universe’s best videos on everything from Einstein's theory of relativity to what it would take to live on Mars. Brush up on the science, philosophy and mystery of space, because the fabric of the universe is the same fabric that connects us all.

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  • Narrator Don Lincoln
  • Director Gatze Zonneveld

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