The Night Sky, Explainedby Dmitry Shteynbuk
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Beyond the SunDefinedTerm

Redshift

The stretching of light to longer wavelengths as an object moves away.

Used to measure recession velocities of galaxies and, via Hubble's law, their distances.

Used in these guides

  • The Milky Way: Reading Our Own Galaxy from Inside ItBeyond the Sun
  • How Far Is Far: The Cosmic Distance LadderBeyond 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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