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One-Gyro Operations FGS Observations. Tips Feb 21, 2008 Ed Nelan. One Gyro Science - FGS. One-Gyro test included 5 orbits of FGS “astrometry” FGS2r & FGS3 guided FGS1r observed a bright star in POS mode for the duration of the orbit. provides an independent check of PCS performance.
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One-Gyro OperationsFGS Observations Tips Feb 21, 2008 Ed Nelan
One Gyro Science - FGS • One-Gyro test included 5 orbits of FGS “astrometry” • FGS2r & FGS3 guided • FGS1r observed a bright star in POS mode for the duration of the orbit. • provides an independent check of PCS performance. • One of the orbits used FGS2r in “single guide star” mode (no roll star). • This orbit used two targets in FGS1r to detect roll changes. • Merle Reinhart scripted the phase2 proposal (11078).
Visit 01 V=13.9 V=13.0 Upgren69 V=9.6
Visit 02 V=14.2 Upgren69 V=9.6 V=13.7
Visit 03 V=14.0 Upgren69 V=9.6 V=13.7
Visit 04 star1 V=9.6 guide star V=13.3 Star2 V=13.1
Visit 6 V=14.2 star1 V=9.6 V=12.9
One Gyro Science:observed jitter in FGS1r * This is the standard deviation of the FGS1r centroids
One Gyro Mode:astrometry summary • FGS1r observations under 1-gyro mode suggests that PCS performance is not degraded relative to 2-gyro (or 3-gyro) operations. • Visit 04 (single guider) did not exhibit any roll changes greater than what is observed under single guider in 2-gyro & 3-gyro operations. • Single FGS guiding appears to be “fine” in 1-gyro operations. • There appears to be no reason to avoid using faint guide stars (V~14) in 1-gyro operations.