Preparing for GRACE Follow-On: will we benefit from higher precision inter-satellite range measurements?

The twin satellites of NASA’s Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission launched on May 22 and will soon be producing data for the continuation of gravity field studies. Within the GRACE framework, solutions of the Earth’s gravity field are generated from high precision measurements of the inter-satellite range, which were measured with a microwave interferometer in the original GRACE mission. GRACE-FO houses both an evolved version of this microwave interferometer and an experimental laser ranging interferometer (LRI), which has the potential of increasing the precision of inter-satellite range measurements by an order of magnitude. Previous modelling studies have made pessimistic conclusions regarding the capacity for the LRI to improve the accuracy of gravity field solutions, claiming the inter-satellite range measurement is not the limiting factor of accuracy. 


This talk will present the results of an undergraduate research course in which I assessed the effect of numerical post-processing errors and on-board accelerometer errors on gravity field solutions. These results paint a more optimistic picture of the possibilities of LRI on GRACE.