"Jerry Martes" wrote in
news:QFxTi.27907$DX.11271@trnddc06:

does not charge for his program. He is an amateur, interested in
providing good data, and I consider you to be a good critic.

Hi Jerry,

That is flattering, but undeserved I am sure.

There are a lot of calculators on the 'net for giving the Sun's position
at a place and time, and they use varying algorithms for more or less
accuracy.

The routines I used in the spreadsheet were unashamedly the work of some
one else, the chap who converted them to VBA and the original NOAA
javascript routines behind their page at
http://www.srrb.noaa.gov/highlights/sunrise/azel.html . I have accepted
they were good enough for my application, and they seemed quite close to
another navigator application that I have.

Owen