Category

Stars

Angular Measurements of the Sky

In Astronomy, and more so, in the subfield of Astrometry, you will often refer to measurements on the sky in a fashion that you are not used to.

On Earth, we talk about separations and distances in the Imperial system (inches, feet, etc) or the Metric system (meters, km, etc).

In Astronomy, you have to remember that we are viewing the night sky on the celestial sphere. Therefore, we refer to separations in spherical terms.

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