Celestial Navigation · Meridian Altitude
Local apparent noon (LAN) occurs at the instant the Sun:
- ARises above the visible horizon
- BCrosses the observer's meridian, reaching its maximum altitude✓ Correct
- CBears due east of the observer
- DIs 6° below the horizon
Explanation
At LAN the Sun is on the observer's meridian (LHA = 0°) at its highest altitude of the day. The meridian altitude gives latitude directly without sight-reduction tables, and the time of LAN can be used to check longitude.
Authority: Bowditch (Pub. No. 9)
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