Himanshu Save, Center for Space Research, The University of Texas at Austin, USA.

The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission was launched on May 22nd 2018. GRACE-FO extends the 15 year time-variable gravity field time series established by the GRACE mission from 2002 to 2017. GRACE-FO carries a new Laser Ranging Interferometer (LRI) instrument, as a technology demonstration, in addition to the heritage K-Band microwave Ranging (KBR) instrument. LRI shows great potential for improved accuracy and precision in the estimation of the gravity field. Operating with a much shorter wavelength than the KBR instrument, the LRI allows for a significantly higher ranging precision compared to KBR. The GRACE Follow-on (GRACE-FO) mission is continuing the unprecedented measurements of mass anomaly time-series started by GRACE over 17 years ago. The interpretation of the satellite-to-satellite tracking data has improved over these years and have yielded several innovative mass anomaly products at the Center for Space Research (CSR) at the University of Texas at Austin. This paper discusses the evolution of the different gravity field and mass anomaly products developed at CSR. These include spherical harmonic solutions, regularized spherical harmonics fields, Mascon grid estimates etc. This paper presents the details on several different types of solutions which capture higher frequency signals like the regularized sliding window mascons (RSWM) and daily swath solutions that compute daily mascon estimates near daily ground tracks. The paper also describes the low latency products like the quick-look solutions from GRACE-FO, which open the possibilities for near real-time applications of GRACE-FO. The use of the higher precision LRI data opens new possibilities for GRACE-FO products. This paper also discusses the evolution and innovation of these products for the future gravity missions.