Celestial Navigation · Hour Angle
An LHA of 000° means the body is:
- AOn the observer's celestial horizon
- BAt its lowest altitude
- COn the observer's meridian (upper transit), at maximum altitude✓ Correct
- DBearing due east of the observer
Explanation
When LHA = 0°, the body's hour circle coincides with the observer's meridian — the body is at upper transit (culmination), its highest altitude. This is the basis of the meridian-altitude (noon) latitude sight.
Authority: Bowditch (Pub. No. 9)
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