Quantum gravimetry for future satellite gradiometry

The present electrostatic accelerometers (EA) drift at low frequencies. To address this problem, integrating a cold atom interferometry (CAI) accelerometer could be beneficial, as it offers the potential for superior long-term stability. The CAI-based accelerometers (CAI ACC) are accurate and stable, but they have some issues with long dead times and a relatively small dynamic range. A way to address these problems is to combine a CAI ACC with an EA in a hybrid configuration. Using CAI ACC in an upcoming satellite gradiometry mission can give stable and accurate measurements of the static Earth’s gravity field. Three scenarios have been considered in this study: first, a realistic scenario involving current-generation and realistic hybrid accelerometers; second, a semi-realistic scenario with the same accelerometers and an accurate gyroscope; and third, using highly accurate hybrid/CAI accelerometers with an optimistic gyroscope. One significant aspect was on detecting temporal gravity changes, which cannot compare to the effectiveness of the low-low satellite-to-satellite tracking (LLSST) principle. But, quantum gradiometers can significantly enhance solutions for the static gravity field, provided one has accurate observations of the satellite orientation available.