Asteroid, Comet, and Satellite Catalogs

After learning to program with PyEphem, you will probably want to download the orbital elements of comets or asteroids that interest you, or perhaps coordinates for stars and other fixed objects. Here are a few sources from which such data may be obtained:

Orbital elements for man-made earth satellites are available from NORAD, whose Two-Line Element format can be understood by PyEphem’s readtle() function.

This page has elements in ephem format for several of our longer-lived space probes.

If you need more information about the XEphem database format itself, here is the link where the format is defined in XEphem’s own documentation.