Local Hour Angle

Local Hour Angle, abbreviated LHA, is calculated from your assumed longitude, adjusted by the GHA. It is theĀ angle between the meridian of your Assumed Position and the meridian of the geographical position of the celestial body. As this is one of the values used in Section IV to calculate a Line of Position using the Sight Reduction Tables, which handles whole degrees only, the LHA needs to have no arcminutes nor arcseconds, accounted for when we choose an Assumed Position.

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