[G01-4] Combination and co-location of space geodetic techniques

[G01-4-02] Lunar Laser Ranging as tie between terrestrial and space reference systems

Franz Hofmann, ^○Juergen Mueller (Leibniz Universitaet Hannover, Hannover, Germany)

Lunar Laser Ranging (LLR) data has been used since 1969 to determine various physical parameters of the Earth-Moon system. LLR also acts as the connecting technique between the reference systems fixed on Earth, Moon and in space. The estimated reflector coordinates in combination with the lunar ephemeris represent the selenocentric reference frame and its orientation with respect to the barycentric reference frame. LLR can contribute to the terrestrial reference frame, e.g., with the estimation of station coordinates and velocities and long-periodic nutation coefficients with periods between 0.5 and 18.6 years. The estimated accuracy of the nutation coefficients is about 0.1 milliarcsecond. The estimated accuracy of the coordinates and velocities of the stations on Earth is in the order of 1 cm and 1 mm/yr which is up to now one order of magnitude larger than the GGOS goals for the terrestrial reference frame. The deployment of new single-corner-cube reflectors on the Moon and the recent success in infrared ranging to the Moon at the French station in Grasse can help to get more accurate LLR data per year. Based on the LLR dataset up to the end of 2016 we show the recent results for the estimated reflector and station coordinates, station velocities and nutation coefficients. With simulated future data we illustrate possible improvements for these parameters within the next years up to 2030.