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Re: Real accuracy of the method of lunar distances
From: Frank Reed CT
Date: 2004 Jan 12, 15:32 EST
From: Frank Reed CT
Date: 2004 Jan 12, 15:32 EST
Fred, you earlier wrote:
"One clear point that came out of Bolte's paper from the 1870s
referenced by Jan Kalivoda was that there's little difference in
precision between lunars taken with stars and lunars taken with the
sun. Additionally, taking two lunars, one in either direction from the
moon (and equally spaced), is more accurate than taking one. Then at
least one of the objects would need to be a star or planet. I vaguely
recall Chauvenet also making this second point. "
In this message, if I understood you correctly, you were saying that sights on both sides of the Moon would yield better results because "at least one of the objects would need to be a star or planet." (this was at the point when you were contesting my statement that Moon-Sun lunars are easier to shoot accurately than Moon-star lunars). You agree that that's not what Chauvenet was getting at, right? He was talking about eliminating errors from inadequately determined index correction and, if you're lucky enough to find objects the same distance on either side of the Sun, eccentricity error. It's interesting that Chauvenet comments that errors of eccentricity are "not readily determined". Apparently, star-to-star sights did not occur to him.
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois
"One clear point that came out of Bolte's paper from the 1870s
referenced by Jan Kalivoda was that there's little difference in
precision between lunars taken with stars and lunars taken with the
sun. Additionally, taking two lunars, one in either direction from the
moon (and equally spaced), is more accurate than taking one. Then at
least one of the objects would need to be a star or planet. I vaguely
recall Chauvenet also making this second point. "
In this message, if I understood you correctly, you were saying that sights on both sides of the Moon would yield better results because "at least one of the objects would need to be a star or planet." (this was at the point when you were contesting my statement that Moon-Sun lunars are easier to shoot accurately than Moon-star lunars). You agree that that's not what Chauvenet was getting at, right? He was talking about eliminating errors from inadequately determined index correction and, if you're lucky enough to find objects the same distance on either side of the Sun, eccentricity error. It's interesting that Chauvenet comments that errors of eccentricity are "not readily determined". Apparently, star-to-star sights did not occur to him.
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois
