Greenwich Hour Angle (GHA): The angle measured at the pole between the meridian passing through Greenwich and the meridian passing through the celestial body.

 

Local Hour Angle (LHA):

The angle measured at the celestial pole between the meridian passing through the observerís meridian and the meridian passing through the celestial body.

 

Sidereal Hour Angle (SHA):

The angle measured at the celestial pole between the meridian passing through the first point of Aeries and the meridian passing through the celestial body, measured westwards.

 

The Almanac gives the GHA of everything but the stars because that would take up too much room, instead it gives the SHA, which we can use to convert, and worksheets help us figure the LHA by using our longitude.

 

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