GRACE/GRACE-FO and LAGEOS/LARES in Geodesy, Earth Observation and Relativity

GRACE, launched in 2002, and its continuation GRACE-FO, to be launched end of 2017, are dedicated missions for the measurement of the time variable gravity field. We will briefly summarize the major achievements of GRACE in Earth observation so far. In 2004 the early GRACE static gravity field models firstly allowed to measure frame-dragging or the Lense-Thirring (LT) effect by Satellite Laser Ranging (SLR) observations to the LAGEOS satellites with an accuracy of 10%. In 2012 the LARES satellite was launched to complement the LAGEOS constellation, goal of the mission is to improve the accuracy of the LT measurement by one order of magnitude. We will briefly summarize the impact of LARES into geodesy before we focus on the relativity aspect. First results on the LT measurements with LARES are published reporting an accuracy of about 5%. We will independently repeat the LT analysis with a longer data span based on a suite of new gravity field models.