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Dave W wrote:
> Is it appropriate to use Local Mean Time as being
> synonymus with Zone Time?
No.
> My notion of LMT is the time when some event is
> going to occur at the prime meridian.  The
> presumption being that this event will then occur
> at every other meridian.
That is essentially true for specific cases, such as the time of
meridian passage or the time of sunrise/sunset.
>
> or
>
> LMT corrected for longitude (ARC to time) yields
> GMT.
Yes.  Also, LMT corrected for the difference in longitude between
your meridian and the zone meridian (even multiple of 15 degrees
of longitude) yields ZT (and vice versa).
>  GMT corrected for zone description (+ or -)
> gives ZT.
Yes.
> If you take a test that says "At 1945 hours,
> after passing Catalina Island and establishing an
> evening star fix..."
>
> then
>
> The next statement reads "All times on this test
> are either LMT or UT"
>
> What kind of time would you take 1945 hours to be?
I would take it to mean ZT, irrespective of the next
statement.  I think the person who wrote the test goofed.
Usually the only time you care about LMT is when computing
the time of meridian passage or the time of a solar event
such as sunrise/sunset/twilight.
Chuck Taylor
Everett, WA, USA

   

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