OSO 3

Description

The objectives of the OSO satellite series were to perform solar physics experiments above the atmosphere during a complete solar cycle and to map the celestial sphere for direction and intensity of UV light, X-ray, and gamma radiation. The OSO 3 platform consisted of a sail section, which pointed two experiments continually toward the sun, and a wheel section, which spun about an axis perpendicular to the pointing direction of the sail and carried seven experiments. Attitude adjustment was performed by gas jets and a magnetic torquing coil. Data were simultaneously recorded on tape and transmitted by PCM/PM telemetry. A command system provided for 94 ground-based commands. The spacecraft performed normally until the second onboard tape recorder failed in July 1968. The spacecraft was put in standby condition on November 10, 1969, and became inoperable shortly thereafter. For more details, see J. C. Brandt, Solar Phy., v. 6, p. 171, 1969.