On-orbit performance of the Far Ultraviolet Spectroscopic Explorer satellite

The launch of the Far Ultraviolet Spectroscopic Explorer (FUSE) has been fo llowed by an extensive period of calibration and characterization as part o f the preparation for normal satellite operations. Major tasks carried out during this period include the initial coalignment, focusing, and character ization of the four instrument channels and a preliminary measurement of th e resolution and throughput performance of the instrument. We describe the results from this test program and present preliminary estimates of the on- orbit performance of the FUSE satellite based on a combination of these dat a and prelaunch laboratory measurements.