Celestial Sphere
- Precession of the Equinoxes is westwards.
Local Standard Time = Grenwitch Sidereal Time + Longitude LST = GST + α
Hour Angle = Local Sidereal Time - Right Ascention (i.e. westwards) HA = LST - RA
// Right Ascention = Local Sidereal Time - Hour Angle RA = LST - HA
