But the Nautical Almanac, now continuing as a separate publication addressed largely to navigators, continued to give tabulations based on mean solar time ( UT ).
32.
The modern molad moments match the mean solar times of the lunar conjunction moments near the meridian of Kandahar, Afghanistan, more than 30?east of Jerusalem.
33.
It is indispensable to know precisely the difference between true solar time of sundials, and mean solar time clocks, especially since the advent of clocks seconds.
34.
In the unusual case that the mean solar time of an observation was needed, one would apply the equation of time to " apparent " solar time.
35.
In the issues since 1834, all times have been in mean solar time, because by then the time aboard ship was increasingly often determined by marine chronometers.
36.
The need for strict timekeeping led the companies to settle on one standard, and civil authorities eventually abandoned local mean solar time in favor of that standard.
37.
Arguments against the proposal include the unknown expense of such a major change and the fact that universal time will no longer correspond to mean solar time.
38.
Analemmas ( as they are known today ) have been used in conjunction with sundials since the 18th century to convert between apparent and mean solar time.
39.
The apparent solar time is a measure of the Earth's rotation and the difference between it and the mean solar time is known as the equation of time.
40.
This compensates for the slight eccentricity in the Earth's orbit and the tilt of the Earth's axis that causes up to a 15-minute variation from mean solar time.
