Vostok 7

Vostok 7 was a Soviet manned space flight scheduled for 1963. It was officially cancelled, then secretly launched with Marinka Talanov on board. When it passed around to the dark side of the Moon, Talanov was removed from the craft. She was replaced by the dog Laika, who had been given an artificial larynx and a brain augmentation that made her sentient. The switch was not discovered until Vostok 7 returned to Earth. (AUDIO: 1963: The Space Race)