Fifty years ago today — August 23, 1961 — Ranger-1 launched from Cape Canaveral on an Atlas-Agena rocket.
(Ranger-1 spacecraft. NASA image.)
Ranger-1 was designed as a pathfinder mission to test components for future lunar and planetary missions. It also carried scientific instruments such as telescopes, particle detectors, a magnetometer, etc., to “study the nature of particles and fields in interplanetary space.”
The Atlas rocket put Ranger-1 in a “parking orbit,” but the Agena upper stage did not restart. Ranger-1 separated from the Agena and ended up tumbling in a low Earth orbit, re-entering the atmosphere a week after it was launched. Thus the mission was counted a partial success: “much of the primary objective of flight testing the equipment was accomplished but little scientific data was returned.”
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