Spacecraft design and flight status of HAYABUSA asteroid explorer propelled by microwave discharge ion engines

The microwave discharge ion engines 'micro10s' are devoted to the main propulsion on 'HAYABUSA' asteroid explorer. In the development program various kinds of tests and assessments were applied to the ion engines and the spacecraft; the endurance test, the EMI susceptibility test, the interference test between plasma and communication microwave, the beam exhaust test on the spacecraft, the assessment on plasma interference with solar array, so on. The spacecraft was input in the deep space by M-V rocket on May 9, 2003. After vacuum exposure and several runs of baking for reduction of residual gas the ion engine system established the continuous acceleration of the spacecraft toward the asteroid 'ITOKAWA'. On the beginning of December 2004 the ion engines reached the total number of space operational time 20,000 hour. And the spacecraft passed by the aphelion 1.7 astronautical unit on February 18, 2005 so that the microwave discharge ion engine micro10s became the electric propulsion to arrive at the furthest space from Sun. It will rendezvous with the target asteroid on September 2005.
JAXA Special Publication
宇宙航空研究開発機構特別資料