Next message: Jim Thompson: "Re: Sextant optics"
I wrote earlier:
" This would require an almanac with heliocentric coordinates for all of the
planets, but that's no problem (the Nautical Almanac from the 1780s included
heliocentric latitudes and longitudes, for some odd reason, but not
distances)."
Ken M replied:
"I think the longitudes and latitudes were to calculate the lunar distances
using the approximate formula..."
That would make sense for the geocentric celestial (ecliptic) latitude
s and longitudes in the almanac, but I'm talking about *heliocentric* lats
and lons. They're labeled as such and just scanning quickly they do indeed
appear to be heliocentric. I can't think of any practical purpose for them. The
Nautical Almanac seemed to have various experimental sections in this early
period. Maybe they were included for astronomers' use...
Frank E. Reed
[ ] Mystic, Connecticut
[X] Chicago, Illinois
