DESCRIPTION AND ANALYSIS OF AN ALGORITHM FOR STAR IDENTIFICATION, POINTING, AND TRACKING-SYSTEMS

Software for star field identification and star pointing and tracking is described. The software will be implemented in the guiding system of UVSTAR, a spectrograph/telescope system for UV astronomy and planetary physics that will operate as a Hitchhiker payload on the Shuttle. The software work with the wide-field CCD camera and an on-board stellar catalog. It is capable of (1) providing high accuracy (better than 2 arcsec) attitude determination from coarse (+/- 3 deg) initial knowledge of the pointing direction and (2) pointing toward the target. It is capable of tracking at the same high accuracy with a processing time of less.than a few hundredths of a second. Simulation of observations and various types of tests are also discussed.