RDS-1 (Russian: РДС-1), also known as Izdeliye 501 (device 501) and First Lightning (Первая молния) was USSR's first nuclear bomb. The United States named the bomb Joe-1, in reference to Joseph Stalin. It was a plutonium implosion-device, like The Gadget (Trinity) and Fat Man, and it had a similar yield. The bomb designers had a more sophisticated design, but it was rejected due to the known reliability of the Fat Man type design, and was later tested on RDS-2. Houses, a bridge and a metro were constructed to test the effects of the weapon. Also, 1.500 animals were brought, as well as 50 aircraft. The resulting data showed that the explosion was 50% more destructive than the estimation by the engineers. The bomb surprised the west powers. The US estimated that the USSR would not have atomic devices until 1953, and the UK estimated until 1954. The bomb was detonated on a tower at Semipalatinsk Test Site, Kazakh SSR, Soviet Union (Now Kazakhstan).
Yield: 22 kt.
Date: 00:00 UTC 29 August 1949
