Diapason

Diapason was a small cylindrical satellite, 20 cm long and 50 cm in diameter which was used for geodetic measurements. Observations consisted of doppler delay of radio signals, plus photography of the satellite against the star field. Satellite performance was satisfactory with useful observations occurring for over 5 years. The satellite, with a mass of 18,5 kg, carries a scientific payload composed of two radio transmitters into low earth orbit. The stable frequency emissions of these radios are what gave the satellite its name. Ground stations measure the Doppler effect of these emissions and deduce the position of the satellites. The satellite carries a technological experiment to measure the effect of radiation on the photovoltaic cells that supply the satellite.