Discoverer 39Rocket launchby USALaunch time18 Apr 196200:54 UTCsuccessOrbit: LEOSerial number: Thor 331MissionRocketPayloadsRocket ThorDM-21 Agena-Blaunched from Vandenberg AFB, LC-75-3-5USAPayloadsNamePurposeMassCommentDiscoverer 39Reconnaissance--