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Re: Sun sights during an eclipse: "bad limb" calculation
From: David Pike
Date: 2023 Oct 5, 14:09 -0700
From: David Pike
Date: 2023 Oct 5, 14:09 -0700
Frank Reed you wrote: “Similarly with Alt/Azm (altitude and azimuth or "horizontal") coordinates on the sky, for small enough differences in coordinates:
dy = dAlt,
dx = cos(Alt) × dAzm. [because azimuth lines converge at higher altitudes]”
At first, I thought “Ah the master stroke.” But then I started to think about it a bit more, and now I’m confused. We’re certain the Sun and the Moon are near enough to perfect spheres. Wouldn’t your suggestion mean they should start to look thinner and thinner as their altitude increases? DaveP
