Dr. John Ries
RESEARCH INTERESTS
Precision Orbit Determination, Space Geodesy, Global Reference Frames, Satellite Laser Ranging (SLR), Relativity.
CURRENT RESEARCH THRUSTS (August 2026)
- Satellite Geodesy
- Precision orbit determination in support of mm-level positioning with SLR
- Determine reliable estimates of geocenter motion from SLR
- Investigate limitations to the determination of the Earth’s gravitational constant from SLR
- Global gravity model determination from space from GRACE and GRACE-FO, with additional emphasis on the variations in the lowest degree coefficients from SLR
- Relativity
- Continue to improve the test of the General Relativity prediction of the Lense-Thirring effect on satellite orbits using SLR and GRACE gravity models
ACTIVE CONTRACT/GRANTS
McDonald Space Geodesy Services and Data Analysis Follow-On (https://csr.utexas.edu/mgo/) – This effort focuses on the management and quality of geodetic instrumentation, including Very Long Baseline Interferometry (VLBI) and Space Geodesy Satellite Laser Ranging (SGSLR) stations.
GRACE Extended Mission (https://csr.utexas.edu/missions/grace/) – A complete reprocessing of the entire GRACE mission data with updated models and processes is the goal of this effort.
Gravity Recovery and Climate Experiment Follow-on (https://csr.utexas.edu/missions/grace-fo/) – This project carries on the extremely successful work of its predecessor while testing a new technology, laser interferometry, designed to dramatically improve the already remarkable precision of the intersatellite ranging system.