Space-based visible metric accuracy

In April 1996 the Midcourse Space Experiment satellite, sponsored by the Ba llistic Missile Defense Organization, was launched into an 898-km altitude, nearly sun synchronous orbit. One of the principal sensors onboard the spa cecraft is the Space-Based Visible, a visible-band electrooptical camera us ed for space surveillance. The instrument is equipped with four adjacent 42 0 x 420 pixel charge-couple devices and was designed with high off-axis str ay light rejection characteristics for observing near the earthlimb, As the first space-based space surveillance sensor, the Space-Based Visible's pri ncipal role is to gather metric and photometric information on a wide varie ty of resident space objects. To assess the metric performance of the senso r, routine on-orbit metric calibration is performed. In addition, a complet e error assessment was made using actual Eight data. The goal of producing 4-arc-s (1-sigma) observations of resident space objects was set during des ign, and early results show that this goal is being reached. The analysis o f each of the error sources within the Space-Based Visible error budget is presented and results from both calibration and routine surveillance data c ollection events are shown, Error sources such as those associated with the sensor boresight pointing, including star catalog errors, spacecraft jitte r, star centroiding, and optical distortion, along with the Midcourse Space Experiment ephemeris and the streak endpoint determination are discussed. The principal finding, as revealed through the discrepency between the theo retical error assessment and on-orbit metric calibration, spawned the ident ification of an unmodeled metric error source for the Space-Based Visible. With the identification and modeling of this error source, a 50% reduction in the metric error budget of the sensor is possible.