Celestial Navigation · Meridian Altitude — Contrary Name
At LAN the sun's Ho is 50°00', it bears due south, and declination is S10°00'. What is your latitude?
- AS30°00'
- BN50°00'
- CN30°00'✓ Correct
- DN10°00'
Explanation
Zenith distance = 90° − 50° = 40°, toward the north (the body bears south, so the observer is north of the GP). Combine signed values (N +, S −): latitude = +40° (ZD north) + (−10°) (dec south) = +30° = N30°. (Check: at N30° a body with dec S10° culminates at 90° − (30° + 10°) = 50°.)
Authority: Bowditch (Pub. No. 9), Latitude by Meridian Altitude
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