A new gravity satellite constellation plan for enhancement in mid-low latitude regions

The launch of the GRACE (Gravity Recovery and Climate Experiment) polar-orbiting gravity satellite in 2002 opened a new perspective on the mass distribution and redistribution in the Earth system, together with its successor launched in 2018, providing valuable gravity data for more than two decades. Taking its value, two established GRACE-like missions are expected to be launched and operated before 2030. Nonetheless, the high cost and insufficient spatial resolution for a GRACE-like mission continue to limit current geophysical applications, requiring an investigation into gravity satellite constellation optimization. To do so, we propose a novel gravity star network covering mid-low latitudes and put a comparison in a closed-loop simulation with the Bender constellation, showing that the new low-cost constellation may have the potential to improve the accuracy and spatiotemporal resolution of gravity field observation, opening up a new way for satellite gravity observation.