This zip file contains some data files useful for use with the orekit library (http://www.orekit.org/). In order to use this file, simply unzip it anywhere you want, note the path of the orekit-data folder that will be created and add the following lines at the start of your program: File orekitData = new File("/path/to/the/folder/orekit-data"); DataProvidersManager manager = DataProvidersManager.getInstance(); manager.addProvider(new DirectoryCrawler(orekitData)); This zip file contains JPL DE 430 ephemerides from 1990 to 2069, IERS Earth orientation parameters from 1973 to June 2016 with predicted date to fall 2016 (both IAU-1980 and IAU-2000), UTC-TAI history from 1972 to mid of 2017, Marshall Solar Activity Futur Estimation from 1999 to mid 2016, the Eigen 06S gravity field and the FES 2004 ocean tides model.