Celestial Navigation · Time
The Nautical Almanac tabulates the positions of celestial bodies against which time standard?
- AUniversal Time (UT1), formerly called Greenwich Mean Time✓ Correct
- BLocal apparent time at the observer's meridian
- CZone time of the vessel's time zone
- DLocal mean time at 180° longitude
Explanation
The Almanac is entered with UT (UT1, the modern successor to GMT). The navigator must convert the watch/zone time of an observation to UT before extracting GHA and declination.
Authority: Bowditch (Pub. No. 9)
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