ABOUT JTRF
Glossary of Acronyms
Below you will find a list of acronyms related to the JPL Terrestrial Reference Frame (JTRF).
For additional acronyms and definitions related to Reference Frames and Geodesy, visit the Outreach and Education section on our About page.
| Abbreviation | Meaning | Learn More |
|---|---|---|
| AR | non-normalized Residual expressed in cm | |
| CF | Center of Figure of the solid Earth surface | |
| CM | Center of Mass of the total Earth system | |
| CM-CN | Center of Mass to Center of Network | |
| CN | Center of observing Network | |
| CTRS | Conventional Terrestrial Reference System | Visit CTRS |
| DORIS | Doppler Orbitography and Radiopositioning Integrated by Satellite, Solutions Data Code: D | Visit DORIS |
| EOP | Earth Orientation Parameters | Visit NASA GSFC SGP EOP definition |
| GGOS | Global Geodetic Observing System | Visit GGOS |
| GNSS | Global Navigation Satellite System, Solutions Data Code: P | Visit GNSS |
| GPS | Global Positioning System | Visit GPS |
| GRACE | Gravity Recovery and Climate Experiment | Visit GRACE |
| GSFC | Goddard Space Flight Center | Visit NASA GSFC |
| GTRS | Geocentric Terrestrial Reference System | Visit GTRS |
| IAG | International Association of Geodesy | Visit IAG |
| IAU | International Astronomical Union | Visit IAU |
| IDS | International DORIS Service | Visit IDS |
| IERS | International Earth Rotation and Reference Systems Service | Visit IERS |
| IGS | International GNSS Service | Visit IGS |
| ILRS | International Laser Ranging Service | Visit ILRS |
| ITRF | International Terrestrial Reference Frame | Visit ITRF |
| ITRS | International Terrestrial Reference System | Visit ITRS |
| IVS | International VLBI Service for Geodesy and Astrometry | Visit IVS |
| JPL | Jet Propulsion Laboratory | Visit JPL |
| JTRF | JPL Terrestrial Reference Frame | |
| KALREF | KALman filter for Terrestrial REference Frame determination | |
| LAGEOS | Laser Geodynamics Satellite | Visit LAGEOS |
| LLR | Lunar Laser Ranging | Visit LLR |
| LOD | Length of Day | Visit LOD |
| LSIG | LOD uncertainty | |
| MJD | Modified Julian Day | Visit MJD |
| NASA | National Aeronautics and Space Administration | Visit NASA |
| NEQs or NE | Normal Equations | |
| NGA | National Geospatial-Intelligence Agency | Visit NGA |
| NNR | No-Net Rotation | |
| NNRC | No-Net Rotation Condition | |
| NNS | No-Net-Scale | |
| NNT | No-Net-Translation | |
| NR | Normalized Residual | |
| NTL | Non-tidal Loading | |
| PMX | Polar Motion X-coordinate | |
| PMY | Polar Motion Y-coordinate | |
| PSD | Post-seismic displacement | |
| RMC | Rotational Minimal Constraints | |
| RMS | Root-Mean-Square | |
| RTS Smoother | Rauch-Tung-Striebel Smoother | |
| SG | Space-Geodetic | |
| SGP | Space Geodesy Project | Visit NASA GSFC SGP |
| SINEX | Solution INdependent EXchange Format | |
| SLR | Satellite Laser Ranging, Solutions Data Code: L | Visit SLR |
| SREF | Square-root Reference frame Estimation Filter | |
| TCH | three-corner hat | |
| TCs | Technique Centres | Visit IERS TCs |
| TR | Temporal Resolution | |
| TRF | Terrestrial Reference Frame | Visit TRF |
| TS | Time span | |
| UAVSAR | Uninhabited Aerial Vehicle Synthetic Aperture Radar | |
| UniLu-GGFC | University of Luxembourg Global Geophysical Fluid Center | Visit UniLu-GGFC |
| USIG | UT1 uncertainty | |
| UT | Universal Time | |
| UT1 | principal form of Universal Time | Visit UT1 |
| UTC | Coordinated Universal Time | Visit UTC |
| VC | Variance-Covariance | |
| VLBI | Very Long Baseline Radio Interferometry, Solutions Data Code: R | Visit VLBI |
| WRMS | weighted root mean squared | |
| XDOT | Time rate-of-change of PMX | |
| XDSIG | XDOT uncertainty | |
| XSIG | PMX uncertainty | |
| YDOT | Time rate-of-change of PMY | |
| YDSIG | YDOT uncertainty | |
| YSIG | PMY uncertainty |