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From: Bill (no email)
Date: Sat Apr 09 2005 - 21:48:26 EDT
> Bill wrote
> "Moon was approx. 53d, and dim against the sky. Given the Sun was lower, it
> might have made sense to us it in the horizon glass instead of the Moon, but
> it seemed easier to have the Moon in the glass as it was difficult to see."
> Frank Replied
> This is probably another reason why navigators in the 19th century seem to
> have avoided lunars when the Moon's elongation was less than about 50 to 60
> degrees. The contrast against the sky is just too darn low. Of course, they
> could have waited until dark and used stars if really necessary.
Popped out to do a lunar April 4 at noon EST, Long 86d 56.' Moon should
have had an Hc about 20.5d, and bearing of approx. 217d. Blue sky, bit of
haze on the horizon. For the life of me could not see it. Rechecked my
calculations against Omar's Navigator Star Finder,
http://www.tecepe.com.br/cgi-win/cgiasvis.exe
and went out with binoculars. True I was dodging trees but changed my
vantage point often, and checked the azimuth with a compass corrected for
magnetic declination. Finally hiked to where the tree line was not behind
me. Still nothing! Just walked away scratching my head,
> Frank added
> By the way, that mystery angle you were wondering about... it's the
> difference in azimuth between the two bodies.
Thank you. Admit I have not done due diligence on the "Easy Lunars"
formulas to track the the suspect, but that is the last place I would have
guessed based on angular separation and refraction correction for two
bodies.
Bill
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