[G03-1] Current and future satellite gravity missions

[G03-1-02] GRACE Follow-On: Overview and Current Mission Status

^○Felix Landerer¹, Frank Flechtner², Frank Webb¹, Michael Watkins¹, Christoph Dahle², Srinivas Bettadpur³ (1.Jet Propulsion Laboratory / Caltech, Pasadena, CA, USA, 2.GFZ Posdam, Germany, 3.Center for Space Research, University of Texas, Austin, TX, USA)

The GRACE Follow-On Mission has now advanced to the Assembly and Test Phase with the delivery of essentially all satellite subsystems and science instruments. The two spacecraft have been transferred to Ottobrunn near Munich for several months of operational testing in the IABG test center. The project team is conducting tests of satellite and instrument operation and performance and putting together updated simulations of expected performance on-orbit, including intersatellite ranging (both microwave and laser), accelerometer, thermal variability and deformation, and other errors. In addition, all required ground analysis software of the Science Data System is in development and testing at JPL, UTCSR, and GFZ, in preparation for fully integrated end-to-end (international) testing from Level-1 through Level-3 data within 2017. Recently, the GRACE Follow-On launch was confirmed in a rideshare agreement between GFZ and Iridium Satellite LLC. GRACE Follow-On is expected to launch in the period from December 2017 to February 2018, together with 5 Iridium-Next satellites, on a Space-X Falcon-9 from Vandenberg Air Force Base in California.
In this presentation, we will provide the detailed status of project integration and test, the latest results of expected science performance, and schedule for remaining project milestones before and after launch.