Celestial Navigation · Equation of Time
The equation of time represents the difference between:
- ASidereal time and solar time
- BGMT and zone time
- CApparent (sundial) time and mean (clock) time — used to find the time of meridian passage of the sun✓ Correct
- DChronometer time and watch time
Explanation
The equation of time is apparent solar time minus mean solar time, arising from Earth's elliptical orbit and axial tilt. It is used to predict the time of local apparent noon (sun's meridian passage) for the meridian-altitude latitude sight.
Authority: Nautical Almanac; Bowditch (Pub. No. 9), equation of time
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