CHAMP Rapid Science Orbit Determination — Status and Future Prospects

Abstract

The CHAMP Rapid Science Orbit (RSO) is produced to support the atmospheric and ionospheric occultation processors as well as the magnetic/electric field analysis system of the CHAMP Science Data System. The RSO is computed using dynamical models in a two step approach. First the orbits and clocks of the GPS satellites are estimated, then the CHAMP orbit is determined by fixing the estimated GPS orbits and clocks. For quality control external GPS orbits and CHAMP laser observations are used. The GPS orbits are delivered with 14 h latency and with an accuracy of about 10 cm in I-D position, while the CHAMP orbits are delivered with 16 h latency and an accuracy of 5 cm in 1-D position. For the future it is planned to decrease the RSO latency for use in a numerical weather prediction environment.