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J Kalivoda, you wrote:
"These details are  VERY important"

:-) Importance is a relative thing. I'm sure you agree,  that these little
things are important to us lunars addicts. I have finally,  just this evening,
gotten over my "WrapPDF" addiction. I don't think I could  have typed "1-50",
"51-100" many more times without going mad.

So here's  a miniscule detail that the ECCO collection you pointed us to has
finally  resolved for me; when did the "tenth lunars star" expire?

The tenth  lunars star was Beta Capricorni, as you may recall (I brought this
up on the  list a few years ago). For about a decade in the 18th century,
starting with the  very first edition in 1767, lunar distances were included in
the Nautical  Almanac for this star along with the usual nine (that list of
nine lasted for  well over a century). Pre-computed geocentric LDs were available
for Beta Cap  from March through December usually. Since Beta Cap is faint,
these distances  are more or less useless in practice, and their days in the
almanac were  numbered.

I would have supposed that LDs for Beta Cap would end with  some specific
year of the Nautical Almanac. In fact, they were dropped from the  summer months
of the Nautical Almanac for 1777 and then dropped for good  starting in the
almanac pages for August of 1778 (the last day with a Beta  Capricorni LD was
July 15, 1778 --how's that for trivia). This pattern makes at  least a little
sense because both these almanacs were being computed  simultaneously to some
extent. The one for 1777 was completed in January, 1776  and the one for 1778
was finished in June, 1776. So the order, probably from  Maskelyne himself, to
stop computing distances for Beta Cap must have been given  sometime during the
latter half of 1775 leaving the summer months of 1777  unfinished as well as
the second half of 1778. Since these distances were almost  certainly useless
in practice, there would have been no good reason to finish  them out for the
year.

-FER
42.0N 87.7W, or 41.4N  72.1W.
www.HistoricalAtlas.com/lunars

   

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