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What do the abbreviations R.A. and Dec. mean, and how do you use them to find objects in the sky?

Michael Stefik, Orland Park, Illinois
RELATED TOPICS: OBSERVING
Sky coordinates
R.A. means “right ascension” and Dec. means “declination”; these are the two parts of the equatorial coordinate system. Astronomers developed it to correspond to longitude and latitude on Earth.

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