Determination of Center-of-Mass of Gravity Recovery and Climate Experiment Satellites

作者：Wang Furun^*; Bettadpur Srinivas; Save Himanshu; Kruizinga Gerhard

来源：Journal of Spacecraft and Rockets, 2010, 47(2): 371-379.

DOI：10.2514/1.46086

The Gravity Recovery and Climate Experiment (GRACE) mission, launched on 17 March 2002, uses radiometric tracking between twin, coorbiting satellites in a polar 500-km-alt orbit, in order to make detailed measurements of Earth's gravity field. These measurements have led to significant, new insights into climate-driven mass transport in the Earth system. A key element of the GRACE scientific measurement suite is the high-precision accelerometer required to measure the nongravitational accelerations acting on the GRACE satellites. To avoid contamination of nongravitational acceleration measurements, the GRACE mission requires the proof mass of the accelerometer to be positioned within 100 mu m (0.1 mm) of the center-of-mass of satellite. This is accomplished using a dedicated center-of-mass calibration maneuver every few months. This paper describes the GRACE center-of-mass calibration maneuver design and implementation details and presents the data analysis used to routinely measure the center-of-mass offset. Using external validation and internal consistency checks, we show that the GRACE satellite center-of-mass offset is being measured routinely to approximately 25 to 40 mu m precision along the three satellite axes.

• 出版日期2010-4