A pico-satellite HAYATO (KSAT) was launched on the piggyback of HIIA 17 from Tanegashima Space Center on May 21, 2010, and put into a circular orbit of altitude of 300 km. HAYATO has a 10-cm cube structure and is the first CubeSat onboard a Ku-band transmitter. We had successfully caught telemetry signals with a ground control system at Kagoshima University after eleven days of the satellite launch. Despite of a limited operation period, we have confirmed that most of bus components, such as solar cells, a power control unit, secondary batteries, and onboard computer and a Ku-band transmitter, were survived space environment during eighteen days.
