NavList:

Hi George

Lost in the flurry of backsight conversation was this choice nugget, of 21Mar2010. You wrote:

To what purpose? As I explained, David's account "reports that Wales and
Bayley , the astronomers of the expedition, measured Sun lunars of up to
155º!"

With the usual caution to not observe objects below 10 degrees due to refraction, we can then assign the greatest inter-object angle observe-able at 160 degrees. Why? Because 160 + 10 + 10 = 180. In other words, the lunar you wrote about is near to the extreme of possible measurement! Even if we let both objects rise to equal altitudes, neither is above 13 degrees. Clearly, this is a near full moon - sun lunar.

I would like to hear more about this lunar. Were the altitudes computed or observed? Were the Nautical Alamac tables of the day providing angular values in this range? How well did the computation work for them? How does it compare to Bruce Starks result? Frank Reed's result? Do the equations hold at this extreme or do they break down?

My curiosity has been engaged!

Best Regards
Brad

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