Item

Abstract

Numerous active Low Earth Orbiters (LEOs) including ESA Copernicus Sentinel-3/-6 satellites are equipped with Global Navigation Satellite System (GNSS) receivers and laser retroreflectors used for Satellite Laser Ranging (SLR). Commonly, the SLR is used to validate Precise Orbit Determination (POD) products based on GNSS. In 2022, the new realization of the International Terrestrial Reference Frame – ITRF2020 was published, which considers a few innovations, e.g., considering an extended model of post-seismic deformations, annual and semi-annual terms for station coordinates and range biases for the SLR stations. The increasing accuracy of laser observations to Sentinel satellites together with their high-quality GNSS-based orbits allow using space geodetic techniques for various purposes, including the modeling of systematic effects in SLR, improving the SLR-based validation of POD products. We perform the SLR validation of Sentinel-3/-6 POD products provided by ESA Copernicus Service for the entire period of the missions. We introduce the new ITRF2020 realization into the processing and compare the results with solutions incorporating the ITRF2014 realization. We consider the modeling of systematic errors in SLR residuals to Sentinel-3/-6 satellites. We test the estimation of the SLR range and tropospheric bias corrections based on LEO POD products and compare the biases with LAGEOS-based estimates. We analyze the satellite signature effect between SLR stations equipped with CSPAD and MCP detectors. We show that modeling of systematic effects in SLR to LEOs together with considering the high-quality reference frame realizations increase the consistency of SLR observations with Sentinel-3/-6 POD products.