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David

Darling

hour angle (HA)

An hour angle (HA) is the angle between the hour circle of a celestial object and the observer's meridian, measured anticlockwise along the celestial equator. It is sometimes used as a coordinate in place of right ascension. See also equatorial coordinates.

 

The local hour angle (LHA) is the hour angle of a celestial object measured with respect to the observer's local meridian.