Wise Observatory Calendar &
Short Description of the Algorithm
The Sun position is calculated using a few first terms of the Bretagnon & Francou VSOP87.
The VSOP87 theory allowing high accuracy in calculating the Sun
position between the years -2000 and +6000.
The Moon position is calculated using a few first terms from the Chapront ELP-2000/82
In the current version, only one iteration is done in
calculating the moon rise and set. Therefore, the moon
rise and set could be with an offset of up to two minutes.
Since the Sun and Moon position calculations are done in the TT time scale.
The calendar generator uses an estimate of
T between the years 1620
and 2010. For years before or after this period,
T = 0 is taken!
A good reference and general information on calendars is available from: http://astro.nmsu.edu/~lhuber/leaphist.html
Constructed: April 1998, by: Eran Ofek
Created: August 1998