These pages are for providing formulae and programs to calculate the approximate positions of solar system objects. I would welcome feedback on these pages, and any hints or tips you have accumulated. I can be contacted at .
My main focus will be on simple calculations which can be programmed on a cheap programmable calculator. You don't have to boot up a PC (or gently rouse your Mac) just to find the position of Venus, or to work out the phase of the Moon this evening!
These pages are not designed to replace books and reference
works. I make reference to the sources of my material on each
page, with links to the publisher's home page for the book where
possible. I also provide a page with links to other resources for
planetary positions, including some theory and some software.
Most of the software operates under the
The calculations, routines and results given here are approximate! The methods are not suitable for calculating eclipses or occultations, or for long times in the future or past.
Each calculation and program is checked for accuracy over a period of time. I use various 'standard' programs and ephemerides for producing accurate positions, including;
I am adding material to this site on a regular basis - and as some of the pages grow very long, I shall split them down into a series of smaller pages. You are welcome to make links to any page or section of a page in this site - but be aware that the arrangement of the information within each page may change.
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