Role of lunar laser ranging in realization of terrestrial, lunar, and ephemeris reference frames

Dmitry Pavlov

Journal of Geodesy, 94 (2020)

DOI: 10.1007/s00190-019-01333-y

Keywords: Lunar laser ranging, Planetary-ICRF tie, Lunar orientation parameters, Earth orientation parameters, Lunar dynamical model

Abstract

Three possible applications of lunar laser ranging to space geodesy are studied. First, the determination of daily Earth orientation parameters (UT0 and variation of latitude) is rarely used nowadays in the presence of all-year VLBI, SLR, and GNSS data. The second application is the determination of two (out of three) lunar orientation parameters, i.e., daily corrections to the rotational ephemeris of the Moon. It may be of importance for future lunar satellite-based navigational systems. The third application is the tie of the ephemeris frame to the ICRF. It has been studied before, though in this work it is extensively compared to another realization of the same tie, obtained by spacecraft VLBI observations; also, two different EOP series and two different models of tidal variations in geopotential are applied, with different outcomes on the tie. The EPM lunar–planetary ephemeris, along with its underlying dynamical model and software, was used to obtain the presented results. All available observations were processed, since the earliest made at the end of 1969 at the McDonald observatory till the end of July 2019 (Matera, Grasse and also Wettzell observatory which began to provide data in 2018). The results and some open questions are discussed.