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Re: Lewis and Clark lunars: more 1803 Almanac data
From: Frank Reed CT
Date: 2004 Apr 19, 04:38 EDT
From: Frank Reed CT
Date: 2004 Apr 19, 04:38 EDT
cfuhb-etc. wrote:
"How much error would be introduced by simply
plotting in a modern atlas, disregarding precession since 1803? I
don't know."
Not much. As you note (I think), precession doesn't affect "lunar distances". Proper motions of the stars, though, must be taken into account, especially for relatively nearby stars like Aldebaran and Regulus. Fortunately, there are web sites that do these calculations accurately and with minimal fuss. But if you choose to "roll your own", that's not so difficult either....
Frank E. Reed
[ ] Mystic, Connecticut
[X] Chicago, Illinois
"How much error would be introduced by simply
plotting in a modern atlas, disregarding precession since 1803? I
don't know."
Not much. As you note (I think), precession doesn't affect "lunar distances". Proper motions of the stars, though, must be taken into account, especially for relatively nearby stars like Aldebaran and Regulus. Fortunately, there are web sites that do these calculations accurately and with minimal fuss. But if you choose to "roll your own", that's not so difficult either....
Frank E. Reed
[ ] Mystic, Connecticut
[X] Chicago, Illinois
