In all his documents his birth was dated with July 21, 1928; engineering diploma in aircraft engineering from Moscow Aviation Institute, 1953; scientist at the Academy of Sciences; was selected as cosmonaut on 22.05.1967 (AN-1); OKP (cosmonaut basic training): 5/67 - 8/68; he was involved in the Soviet Lunar Landing program; he locked out from cosmonaut training by TsPK director Beregovoy, because Yershov refused to become a member of the Communist Party; later Senior Scientist, Institute of Applied Mathematics, Moscow; in 1982 he resigned from active duty and became a pensioner; he died on complications of cancer.