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Re: Sun sights during an eclipse: "bad limb" calculation
From: Antoine Couëtte
Date: 2023 Oct 19, 02:21 -0700
From: Antoine Couëtte
Date: 2023 Oct 19, 02:21 -0700
Dear Lars,
QUOTE
I have difficulties to understand why refraction does not modify times of contact.
UNQUOTE
It is absolutely true that, as you mention it "the semidiameters are different with and without refraction".
Nonetheless, this is only part of the picture because the refracted distances between centers are also different with and without refraction.
Hence "no refraction" increases not only the SD's, but also and in the same proportion the Sun Center to Moon Center distances. See here (4.1) and (4.2) .
Best Regards,
Kermit
