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From: Bruce Stark (no email)
Date: Fri Jan 06 2006 - 13:49:11 EST
Frank and Doug,
No, I haven't seen the Green Flash, but if I happened to I'd probably count
seconds until picking up time from the watch, so as to have the Greenwich time
of the event. The flash itself would give local time, thus longitude. It would
be an interesting stunt, nothing more.
Dip, refraction and semidiameter, plus 90 degrees, would give the sun's
zenith distance. You could work it either as a time sight or LOP. Azimuth for the
LOP could be had by adding or subtracting the amplitude from 270 degrees, maybe
allowing a bit for the sun's change of azimuth between the time it was on the
celestial horizon and the time of sunset.
Considering how inaccurate the method could be, due to uncertain refraction,
it might do to get local time simply by interpolating the times of sunset
given in the Almanac.
Unfortunately I can't recall reading anything about getting longitude from
the Green Flash, but it's hard to believe it hasn't been proposed at various
times, at least as a curiosity.
Bruce
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