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Mission Profile

International Designation Code 1970-011A
Objectives To study satellite launch technologies by M (Mu) rocket and perform an engineering experiment on the satellite.
Launch Date 13:25, February 11, 1970 (JST)
Location Kagoshima Space Center (Uchinoura)
Launch Vehicle
Configuration Weight 24 kg (after combustion of the 4th motor)
Shape Overall length 1,000mm
Max. diameter 480mm (at 4th motor of rocket)
Equipped with two hook-type antennas and four beryllium-copper whip-type antennas (circular polarization)

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Orbit Altitude Perigee 350 km, Apogee 5,140 km
Inclination 31°
Type of Orbit Elliptical
Period 145 min
Scientific Instruments Longitudinal precise accelerometer
Longitudinal accelerometer
Strain guage-type thermometer
Telemetry transmitter
Beacon transmitter
Pilot transmitter
Installed silver oxide-zinc battery with capacity 5AH as power supply
End of Operation February 12, 1970
Reentered Date August 2, 2003
Operation From 15:56:10 to 16:06:54, about two and a half hours after the launch, a radio signal from OHSUMI was received at Uchinoura to confirm its first revolution around the earth. The radio signal level gradually fell and the next day, February 12, during its 6th revolution, it became very faint. The signal could no longer be detected during the 7th revolution. It is believed that the signal of OHSUMI was lost 14 to 15 hours after launch, probably caused by rapid reduction of power capacity because of higher than expected temperatures. The satellite continued to orbit the earth, and at 05:45 on August 2, 2003 (JST) it reentered the atmosphere and was melted. The reentry location was around Lat. 30°3' N, Long. 25°0' E, over North Africa (border between Egypt and Libya).