This site contains low precision formulas, algorithms and some code for calculating the equatorial, ecliptic and horizon coordinates and the rise, transit and set times of the Sun, Moon and the planets. You will also find some information on plotting star charts, horizon charts and planispheres; all based on the polar and equatorial stereographic projection.
Disclaimer: The methods in this Web site are low precision and are not suitable for celestial navigation, occultation prediction, eclipse prediction or similar circumstances where high accuracy is needed. Thanks to people who have pointed out errors - some are bound to remain so check results against known sources before trusting the methods here.
Latest Addition | VBA module that defines 'user functions' for finding the sunrise/set and times of the three twilights for any latitude. - Added 2nd Jan 2003
| Alt Az from Ra and DEC
| Precession | Sidereal time
Charts | Plotting a planisphere | Plotting an horizon sky chart | Plotting a star chart
Planets | Finder tables | charts ( corrected! ) | Circular orbits | Elliptical orbits | QBASIC elliptical | Kepler's equation
Other satellites | Galilean | Saturn rings
Tools | VBA | Euler | Excel spreadsheet with examples of most methods (no VBA)
About these pages | Who for | How made | Author
Feedback | form: make comments and suggestions |
Latest link | Excel spreadsheets by Thomas Kraus. Thomas has implemented a superb range of Excel spreadsheets that include excellent diagrams and the full planetary series.- added 17th Dec 2002