Project Details
Projekt
Combination of ring laser with LLR and VLBI for optimal EOP determination and prediction
Applicants
Dr.-Ing. Robert Heinkelmann; Professor Dr.-Ing. Jürgen Müller; Professor Dr.-Ing. Harald Schuh
Subject Area
Geodesy, Photogrammetry, Remote Sensing, Geoinformatics, Cartography
Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
Geophysics
Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
Geophysics
Term
since 2026
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 553176123
We will exploit the enhanced ring laser (RL) data for determining Earth Orientation Parameters (EOP) by combining RL with the complementary space geodetic techniques Very Long Baseline Interferometry (VLBI) and Lunar Laser Ranging (LLR). VLBI and LLR are unique in providing the full set of EOP, including the phase of Earth rotation ΔUT1 and precession/nutation. Moreover, they provide the links to the International Celestial Reference System (ICRS) realizations - kinematically via ICRF and dynamically via the Lunar ephemeris. In contrast, RL enable the direct and near real-time measurement of variations of Earth rotation with high temporal resolution. Due to the envisaged improvements of RL measurements and the advance of VLBI and LLR technologies in the Research Unit RING, we will determine a novel set of complete and consistent EOP by rigorously integrating RL, VLBI and LLR data. These unique EOP will cover the full frequency spectrum and provide a largely improved connection between the Earth- and space-fixed reference systems with utmost accuracy. The EOP and frame tie enhanced by RL will allow the determination of the link between lunar ephemeris and the extra galactic frame and a better separation of polar motion and precession/nutation. A further research objective is the prediction of EOP that will then also give improved values at high frequencies and allow the filling of observational gaps that often occur for VLBI and LLR. The three-technique combination will benefit the understanding of all involved techniques and will strongly support a more accurate determination of the specific VLBI and LLR parameters. One example is the worldwide leading tests of Einstein's relativity theory in the Earth-Moon system and beyond that can then be carried out at the next level of accuracy thanks to the RL data. In the first funding phase, we will assess RL-based improvements for geodesy and fundamental physics through global scale simulations. The simulation of technical advance will include number and geographical distribution of the RL. In the second phase, a sufficient amount of observed RL data will be available to fully exploit their strengths.
DFG Programme
Research Units
