XZ Catalog of
Zodiacal Stars

Name: XZ Catalog of Zodiacal Stars
Contributor: Jeff Medkeff (
Date submitted: Feb 6, 1998

The XZ catalog was created at the U. S. Naval Observatory in 1977 by Richard Schmidt and Tom Van Flandern, primarily for the purpose of generating predictions of lunar occultations, and for analyzing timings of these events. It was designed to include all stars from Robertson's Zodiacal Catalog (ZC), the SAO catalog, and the AGK3 catalog that are within 6d 40' of the ecliptic, which is as far as the Moon's limb can ever get as seen from anywhere on the Earth's surface, leaving some margin for stellar proper motions and change in the obliquity of the ecliptic over the course of three centuries. The original version contained 32,221 entries. Since that time, a number of changes have been made in succeeding versions, including better positions and proper motions, and the elimination and addition of stars. The catalog contains visual magnitudes and radial velocities as well as astrometric data.