NavList:

Thanks Frank for noting the article on equation of time.

At the risk of exposing myself as a nerd, and in the hope that other peoples further comments may enlighten me, I will take exception to the content of the article.

It states

1)"What this formula represents simply is the relationship (difference) between apparent solar time and mean solar time at the observer’s position."

My understanding is that the "equation of time" (not really an equation) is the difference between mean time and apparent time not at the observers position but at Greenwich given at 0000 and 1200 for each day.

Zone times and local times take care of observers position.

2)"But this time ( the length of a solar day )is inconsistent because the Earth’s speed in its orbit is not constant, the actual sun, is not always on the celestial equator, and the speed of rotation varies.

I do not understand why one would say the sun is not always on the equator
has something to do with eq'n of time and I'm going to come down against speed of rotation also.

Frank you said " semi-annual declination effect" please explain.

Dave

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