West: GHA 212°23.4′, DR N 41°12′, W 064°33′.

AP latitude N 41°. AP longitude W 064°23.4′ (same minutes as the GHA, 9.6′ from the DR).

LHA = 212°23.4′ − 64°23.4′ = 148°.

East: GHA 212°23.4′, DR S 33°47′, E 015°10′.

AP latitude S 34°. AP longitude E 015°36.6′ (60′ − 23.4′ = 36.6′; 26.6′ from the DR, nearer than E 014°36.6′).

LHA = 212°23.4′ + 15°36.6′ = 228°.

Wrapping: GHA 30°10.0′, DR W 064°02′. AP longitude W 064°10.0′.

30°10.0′ − 64°10.0′ = −34°; add 360°: LHA = 326°.

For a star, find its GHA first: GHA Aries (hour + increment from the Aries column) + SHA. Then the AP and LHA work exactly the same way.

Worked examples