Operational Anomaly of Midori-II (Advanced Earth Observing Satellite II, ADEOS-II)

The Japan Aerospace Exploration Agency (JAXA) did not receive earth observation data from its Advanced Earth Observing Satellite II, Midori-II at its Earth Observation Center in Saitama Prefecture at 7:28 a.m. on October 25, 2003 (Japan Standard Time, JST.)

At 8:49 a.m. (JST), JAXA checked the operational status of Midori-II, and found it was switched to a light load mode (the mode in which all observation equipment are automatically turned off to minimize power consumption) due to unknown anomaly.

Around 8:55 a.m. (JST), communications between the satellite and the ground stations became unstable, and telemetry was not received.

The Katsuura Tracking and Communication Station of JAXA also failed to receive telemetry data twice (9:23 and 11:05 a.m. JST.)

JAXA is currently analyzing already acquired telemetry data. The analysis result of power generation data by the solar array paddle revealed that generated power has decreased from 6kW to 1kW.
JAXA makes our best efforts to have Midori-II back to its normal operation by continuing to analyze the telemetry data and working on to understand the current condition of the satellite at our domestic and overseas tracking stations.

For anomaly cause investigation, JAXA formed the “Midori-II anomaly investigation team” led by the president of JAXA.

For inquiries:

Public Affairs Department

Tel: +81-3-3438-6107/6108/6109