Celestial Navigation · Equation of Time — Time of LAN
The equation of time must be applied when:
- APlotting an intercept
- BReading the sextant altitude
- CPredicting the clock (mean) time of local apparent noon✓ Correct
- DIdentifying a star
Explanation
LAN occurs at 1200 apparent (sundial) time, but mean (clock) time differs by the equation of time (up to about ±16 minutes). To predict the watch time of LAN — so the navigator is ready for the noon sight — the equation of time is applied to the mean time of meridian passage.
Authority: Nautical Almanac; Bowditch (Pub. No. 9)
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