Celestial Navigation · Meridian Altitude
At local apparent noon a navigator finds the Sun's zenith distance is 30°N (sun bore south) and the Sun's declination is 12°N. The latitude is:
- A18° N
- B42° N✓ Correct
- C30° S
- D12° N
Explanation
Latitude by meridian altitude: when zenith distance and declination have the SAME name, add them. ZD 30°N + Dec 12°N = 42°N. (Zenith distance takes the name opposite the bearing of the body; here the Sun bore south, so ZD is named north.)
Authority: Bowditch (Pub. No. 9)
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