The impact of accelerometer calibration approach on estimation of thermospheric density variations

The environmental non-gravitational accelerations observed by ultra-precise electro-static accelerometers onboard Low Earth Orbiters (LEOs) such as GRACE (FO) and Swarm missions provide a unique opportunity to estimate and monitor the neutral thermospheric density variations. One of main challenge in using such ultra-precise accelerometer observations for thermospheric density application is the calibration approach which delivers the realistic non-gravitational forces acting on satellite surface. The realistic scale factor and bias of accelerometers are estimated during retrieval of Earth’s monthly gravity field solutions.

In this contribution, a realistic accelerometer calibration approach based on Earth’s gravity solutions and precise satellite orbits is introduced and its impacts on neutral thermoshperic density variations for some special periods are investigated. This approach demonstrates the potential of using realistic calibrated ultra-prcise accelerometers for neutral thermospheric density studies.