Selene (kaguya) Orbit Determination Results and Lunar Gravity Field Estimation by Using 4-way Doppler Measurements

SELENE (Kaguya) is Japan’s first large lunar explorer aims to obtain the scientific data to investigate the origin and the evolution of the moon and to acquire engineering techniques for the future moon exploration and utilization. The nominal mission phase finished at the end of October 2008, and the extended mission phase started from the beginning of November 2008. In order to perform the additional scientific observation, the Kaguya spacecraft had been put into several sets of different orbits compared to the nominal mission phase. At the end of extended mission phase, Kaguya made a controlled impact to the lunar surface on 10 June 2009. The paper describe the results of the orbit determination of Kaguya from the nominal mission phase to the extended mission phase and the lunar impact analysis and its operation results. The present status of lunar gravity field estimation is also described.