The almanac and calender information presented on the Almanac with Sun and Moon Position and Lunar Events pages was generated by a software algorithm. It is quite accurate, so far it seems to line up well with the reality in the sky.
For the lunar months, the numbering was considered to start with the first new moon of the new calender year, this is somewhat arbitrary and there might be some better suggestions.
The time base for the calculations is UTC. Items calculated for a given day are calculated at 00:00 UTC for that day. The moon Zodiac gives the moons position exactly when it is in a given sign. The sun Zodiac follows the traditional, divide the year up into 12 equal parts method.
Glossary of abbreviations
AGE = Moons age in days since it became new.
D(AU) = The suns distance from the earth, in Astronomical Units.
D(ER) = The moons distance in Earth radii.
Exct Zodiac = Zodiac that the moon is in, exactly, no rounding to a 30 degree window.
LAT = The moons latitude along the ecliptic, in degrees.
LONG or Mn LONG = The moons longitude along the ecliptic, in degrees.
MM/DD/YYYY:HH:MM = Format in date and 24 Hour time UTC.
Sun Age = The number of days since the last spring equinox.
Sun LAT = The Suns latitude along the ecliptic, in degrees.
Sun LONG= The approximate position of the Sun in degrees latitude with reference to the earths equator.
The software to generate the calender data is built in C some of the parts of the code namely the algorithms for the moon and sun position were available on-line from observatories. SAAO- NAO Technical Note No. 46(1978) and Moonlight Cascade Observatory/BBS. Around the algorithms an interface was built that drives the program from the command line. I consider the data to be accurate, but there are no guarantees as with any software.
For more information about the software that was used to generate these calenders go to the
Software Page
Original Build Date:12-2-2007
Last updated 12-2-2007