Celestial Navigation · Sight Reduction — Declination Name
In sight reduction, the latitude/declination relationship is described as 'same name' or 'contrary name.' What does 'same name' mean?
- ALatitude and declination have the same numerical value
- BLatitude and declination are both north, or both south✓ Correct
- CThe body and observer are on the same meridian
- DThe LHA equals the SHA
Explanation
'Same name' means the latitude and declination are both N or both S; 'contrary name' means one is N and the other S. The sight reduction tables have separate 'same name' and 'contrary name' entries because the geometry of the navigational triangle differs.
Authority: Pub. No. 229 / Pub. No. 249; Bowditch (Pub. No. 9), sight reduction
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