HEOS 1

Description

HEOS 1 was an earth-orbiting, spin-stabilized satellite that was launched by ESA. It was basically cylindrical with an axial boom supporting the antennas and the magnetometers. The spin-axis attitude and spin rate were changed by onboard gas jets. The spacecraft objectives were to study interplanetary magnetic fields, cosmic rays, the solar wind, and the magnetosheath. The spacecraft operation was fully satisfactory for 16 months, after which intermittent loss of some solar gate pulses (attitude reference) occurred. By 1974, spacecraft telemetry coverage was 50% and only the magnetic field experiment was operational. The spacecraft reentered the earth's atmosphere on October 28, 1975.