Detailed Modeling of Acceleration Noise in a Simplified Gravitational Reference Sensor for Future Earth Geodesy Missions
Abstract
The desire for increased sensitivity in satellite-based Earth geodesy has led to a motivation for improved measurement of non-gravitational forces acting on the spacecraft. Current geodesy missions use Accelerometers to quantify acceleration with a sensitivity around 10-10 m/s2/Hz1/2, but recent success with a GRS (Gravitational Reference Sensor), as proven on LISA Pathfinder (LPF), has motivated the development of a Simplified-GRS (S-GRS) for Earth geodesy targeting performance < 10-12 m/s2/Hz1/2. We used simulations and noise-models from LPF to quantify the acceleration noise performance of a S-GRS in a future Earth geodesy mission. Using environmental data from the GRACE-FO mission, simulations have been developed to determine acceleration noise contributions from gravitational, thermal, electrostatic and magnetic effects. Magnetic disturbances depend on both the internal spacecraft and Earth field. In order allow for relaxed magnetic cleanliness requirements, the performance of a magnetic shield for the S-GRS has also been investigated. This study shows that an acceleration noise less than 10-12 m/s2/Hz1/2 is feasible in a GRACE-FO like mission and on a drag compensated platform at lower altitudes.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.G15A0341K