Greenwich hour angle

Greenwich hour angle

(grin -ij, -ich, gren -,) (GHA) The hour angle of a celestial body or point on the Greenwich meridian. It is equal to the Greenwich sidereal time minus the right ascension (in hours) of the body or point.

Greenwich hour angle

[′gren·ich ′au̇r ¦aŋ·gəl] (astronomy) Angular distance west of the Greenwich celestial meridian; the arc of the celestial equator, or the angle at the celestial pole, between the upper branch of the Greenwich celestial meridian and the hour circle of a point on the celestial sphere, measured westward from the Greenwich celestial meridian through 360°. Abbreviated GHA.

Greenwich hour angle

The arc of the equatorial westward through 360° and measured from the celestial meridian of the Greenwich to the hour circle of the body.