MGO Instrumentation
MGO employs three main techniques used in space geodesy research:
- Space Geodesy Satellite Laser Ranging (SGSLR)
- Global Navigation Satellite System (GNSS),
- Geodetic Very Long Baseline Interferometry (Geodetic VLBI)
To meet requirements for characterizing the Terrestrial Reference Frame (TRF) at 1 mm accuracy and 0.1 mm/year stability, these colocated systems are “tied” together through (a) a precise initial site survey and (b) several ongoing local motion monitoring techniques.
Why multi-technique core sites?
- VLBI orients the TRF to the celestial sources (quasars) and constrains the scale of the TRF.
- SLR provides absolute scale and connects the TRF to the center of mass of the Earth System.
- GNSS provides spatio-temporal densification and dissemination of the TRF.
Gravity measurements are added to integrate geometry and dynamics – Geoid-based height systems are the basis for US National Spatial Reference System
Research is being carried out by the University of Texas at Austin to help reduce the km-scale network of instruments to mm-precision (virtual) fiducial point.
- Signal propagation and environmental effects – measurement and modeling
- Inter-technique ties, needed for synthesis
- Instrument system characterization (bias, drift, etc)