Denpa

Launch data: Designation 06152 / 72064A Launch date 19 Aug 1972 - 11:40 JST Launch site Kagoshima Space Center Launch vehicle Mu-4S (#4) Mission Scientific: ionosphere study Elliptical Earth orbit on: Perigee / Apogee  250 x 6570 km Eccentricity   Inclination  31 deg Period  157.4 min

Credit: JAXA

Spacecraft data: Prime contractor   Platform   Operator   Mass at launch  75 kg Dry Mass   kg Basic shape  Octagonal cylinder Dimension (m)  dia= 0.712m height= 0.685m Equipment   Solar array   Stabilization   Propulsion   DC power

Credit: JAXA

Scientific Instruments:

• Electromagnetic wave and plasma wave monitor, etc

Decay:

Mission details:

• Objectives: Conduct observation of plasma waves, plasma density, electron flux, electromagnetic waves, geomagnetism, etc. to study plasma filling the entire solar system.
• After the satellite’s insertion into orbit, the antennas for scientific observation, magnetometers and electron temperature sensor were confirmed to be extended. All the observation instruments and onboard systems were operable and power output of the solar cells was also as planned. At 09:04 (JST) on August 22, three days after launch, ground commands were transmitted but no response from the satellite was received. It was thought that the satellite's power-supply circuit malfunctioned causing discharge that eventually damaged semiconductor components such as transistors vulnerable to overvoltage.
• Results:Until loss of communication with the satellite, data reception was as planned. We obtained data on the plasma density of the ionosphere and magnetosphere, electron temperature, the intensity spectrum of VLF-electromagnetic wave, LF radio emission, geomagnetic field distribution, etc.