The Night Sky, Explainedby Dmitry Shteynbuk
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Naked-eye astronomyDefinedTerm

Right ascension

The celestial equivalent of longitude, measured in hours, minutes, and seconds.

One hour of RA equals 15 degrees. The zero point is the vernal equinox.

Used in these guides

  • The Celestial Sphere: How the Sky Is OrganizedNaked-eye astronomy
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