Space Telescope Motion Limitations for Fine Guidance Sensor Astrometry

Basic Fine Guidance Sensor data have been simulated to correlate the Power Spectrum Densities (PSD) of the Space Telescope motion disturbances with the “seeing” of an astrometric target. The goal of this study is to describe whether a complete identification of the jitter of the line of sight during an astrometric observation is required to improve the precision of this observation. The present preliminary results indicate that the performance in Astrometry are close to the predictions.