The Night Sky, Explainedby Dmitry Shteynbuk
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How stars workDefinedTerm

Light-year

The distance light travels in one year — about 9.46 trillion kilometers.

Not a unit of time. Proxima Centauri is 4.24 light-years away.

Used in these guides

  • The Milky Way: Reading Our Own Galaxy from Inside ItBeyond the Sun
  • Hubble, Leavitt, and the Night the Universe Got BiggerHow we learned where we are
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The Night Sky, Explained — by Dmitry Shteynbuk, Miami, Florida

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