Celestial Navigation · Sight Reduction — Same vs Contrary Name
If the observer's latitude is N and the body's declination is S, in sight reduction they are:
- AAlways equal
- BSame name
- CContrary name✓ Correct
- DCircumpolar
Explanation
Latitude and declination are 'same name' when both are north or both south, and 'contrary name' when one is north and the other south. The table entry and the sign rules for the altitude difference depend on this distinction.
Authority: Pub. 229 / 249; Bowditch (Pub. No. 9)
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