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Bruce, you asked:
"Frank do you have any idea about the type of accuracy that our Antarctic travelers could expect?  

For the sort of observation I described, timed manually, and given a standard 
lunar limb profile, you could expect an accuracy in the position of one 
nautical mile or better. With somewhat better timing and using a really good 
limb profile, you could get a fix accurate to 100 feet. Note though that part 
of this depends on the geometry. If that cylindrical shadow is striking the 
Earth's surface at a shallow angle, then the accuracy of that line of 
position is reduced. So avoid stars that are directly above/below the Moon 
when the Moon's altitude is low. If the stars are left or right of the Moon, 
the edge of the shadow intersects the Earth's surface vertically so there's 
no loss in accuracy.

"I am now looking at the moon with new eyes and trying to see some actual oculting of stars."

The best time to watch for faint star occultations is when the Moon is waxing 
and as far from full as possible. Then the leading edge of the Moon is dark. 
When the Moon is waning, there are just as many emmersions from occultation. 
You can time those, too, but it's more difficult unless you're recording a 
video.

You concluded:
"I love the smell of roasting penguin in the morning. It smells like astronavigation!"

Ha! ;-)

-FER




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