NavList:

Dave,

It took me some time to figure out that in [NavList 12638] you were (still :-)) ) working on the 04 Aug Example, while we had been so actively busy since on the 7-11 September example.

You layout is very instructive. And thank you very much for sharing it with us.

You then mentioned :

QUOTE

Attached shows my values of lat plotted vs height of eye with Antoine's; agreement to a mile or so. As said, variation likely due to refraction model differences. (Also, just to get going quicker, I neglected flattening and oblateness.)

UNQUOTE

Well, although both bodies are low, i.e. refraction is high, I am just surprised that the diffrence is so high "a mile or so" just because of different refraction algoritms. At low altiudes and especially for the Moon, flattening and oblatenes can become significant. Since I am always computing for both, to-morrow I will rework this example on Frank's On Line Computer which has the options of "no flattening" and/or "no oblateness" and see the importance of both effects in this specific case. They may not reach a full mile, but I woulf be surprised should their combined effect stay under 0.3' to 0.4'.

We will see to-morrow ...

Best Regards till then

Antoine M. "Kermit" Couëtte
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