OSCAR 2 is the second amateur radio satellite launched by Project OSCAR into Low Earth orbit. OSCAR 2 was launched June 2, 1962, by a Thor-DM21 Agena B launcher from Vandenberg Air Force Base, Lompoc, California. The satellite, a rectangular box weighing 10 kg (22 lb), was launched as a secondary payload (ballast) for Corona 43, the fifth launch of a KH-4 satellite.