Discoverer 36 (1961 Alpha Kappa 1) was launched December 12, 1961, by the U.S. Air Force Space Systems Division into a polar orbit (perigee 148 miles, apogee 280 miles, inclination 81.2 deg) with a period of 91.5 min. The program objectives consisted of testing various space vehicle components, continuing evaluation of the Agena vehicle and recovery system, conducting experiments in radio propagation and radiation effects, and testing of instrumentation for nuclear explosion detection. The re-entry capsule was recovered from the ocean after four days and 64 orbits. The Discoverer 36 spacecraft re-entered March 8, 1962 (86 days after launch). The spacecraft weighed about 2100 lbs including 300 lb for the capsule, retrorocket, and recovery aids. Discoverer 36 carried, in addition to the capsule intended for recovery, a 10 lb piggyback satellite 'OSCAR' (Orbiting Satellite Carrying Amateur Radio) to beam signals to ham radio operators.