Mariner 2

Mariner 2 was an American space probe launched by NASA in 1962 to study the planet Venus, becoming the first robotic space probe to conduct a successful planetary encounter. The launch and tracking of early space probes required extensive global radar and telemetry networks. Anomalous radar returns or visual sightings of booster stages associated with such launches were sometimes reported to military authorities as unidentified objects.

Space probes like Mariner 2 and their associated launch vehicles are historically significant in UAP archives as they occasionally generated anomalous radar tracks or visual misidentifications.