Next message: Jan Kalivoda: "Re: Lunars on Sep 20th. (was Re: Perpendicularity check)"
A couple of weeks ago, regarding the quadratic correction in series solutions
of lunars, I wrote:
"The quadratic correction was small enough and simple enough that it did
not seem to generate much variation in method. But Bowditch did change things
a little bit in later years. Instead of using the double look-up procedure
that you're familiar with from Norie's table XXXV, Bowditch printed tables
that
simply listed all possible values for each minute of the Moon's HP. To avoid
dealing with negative numbers, he added 18 arcseconds to all these values and
subtracted 18 arcseconds from the Moon's correction table. "
Correction: there is only one table in Bowditch for the quadratic correction.
It's calculated for a mean value of the Moon's HP, namely 57'30". This can
lead to small errors, as Bowditch notes in a footnote.
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois
