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Re: Sun sights during an eclipse: "bad limb" calculation
From: Lars Bergman
Date: 2023 Oct 10, 06:10 -0700
From: Lars Bergman
Date: 2023 Oct 10, 06:10 -0700
Geoff, yes your results are interesting.
Comparing your numbers with mine (for the same UT), they generally agee to the third decimal of a degree. Now, at 18:20:40 UT the altitude of the moon's center is practically equal to that of sun's LL, and the reduced azimuth difference is equal to the moon's semidiameter. Thus any very small difference in say moon's semidiameter will have an observable impact on the exact time of contact amounting to several seconds of time, due to the slow passing of the moon relative to the sun.
We have been using different ephemeris (I used Frank's) and got slightly different results, but in my opinion we are both spot on!
Lars
