Course / Glossary

Celestial navigation glossary

Celestial meridian

The hour circle through your zenith; LHA is measured west from it.

Where the course teaches it

LHA on the celestial sphere, in the module The assumed position and LHA. Choose the assumed position the tables need, and find LHA for any body.

Taught alongside it

Local hour angle (LHA)
The GP’s angle west of your meridian: GHA plus east longitude, or minus west.
Assumed position (AP)
A position near the DR chosen to give whole degrees of latitude and LHA, to enter the tables.