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Referring to the Wikipedia entry which read-

"[edit] Theory
If there are two people, one at Greenwich and one 15 degrees West, the time
by the sun will be one hour later at 15 degrees West. So, if the person
observes the position of the moon at Greenwich at noon and another person
observes the moon 15 degrees west of Greenwich at their locally determined
noon, then due to the one hour difference, although the sun is at its
zenith, the moon would have moved approximately its own diameter across the
sky."

Fred Hebard wrote-

| I read that to mean they are determining the time of local apparent
| noon, and that it will be one hour later 15 degrees west.

Well, the time of local apparent noon is always noon.

=================

| Would you or Frank expand on what was wrong with the use of the word
| zenith?

Fred's question is easy to answer.

The zenith is the point that's directly overhead to the observer. But (on a
particular day), there's only one latitude at which the Sun passes overhead.

What the Wikipedia entry is referring to is the time when the Sun reaches
its highest point, which will not in general be overhead, at the zenith, but
somewhat lower.

However, we can all guess what he really means.

George.

contact George Huxtable at george@huxtable.u-net.com
or at +44 1865 820222 (from UK, 01865 820222)
or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.


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