Category
page 11951 in the Soviet Union
Operation North
mass deportation of Jehovah's Witnesses to Siberia

1951 Polish–Soviet territorial exchange
largest peaceful territorial exchange in history
RDS-3
RDS-3 () was the third atomic bomb developed by the Soviet Union in 1951, after the RDS-1 and RDS-2. It was called Marya in the military. The bomb had a composite design with a plutonium core inside a uranium shell, providing an explosive power of 41.2 kilotons. The RDS-3T () was a modernized version and the first mass-produced nuclear weapon by the Soviet Union. It was assigned to Long Range Aviation in 1953.
RDS-2
The RDS-2 (Russian: РДС-2) was a second nuclear bomb developed by the Soviet Union as an improved version of the RDS-1. It included new explosive lenses along with a new core design to decrease the probability of pre-detonation or 'fizzle'. The levitated core increased implosion efficiency by allowing for an empty space between the "flying layer" and the core, thereby allowing rapid acceleration of the shock wave before it impacted the core.
1951 anti-Chechen pogrom in Kazakhstan
Pogrom
Dezik and Tsygan
two Soviet dogs, first higher animals to survive a spaceflight
Operation Osen
1951 mass deportation from Lithuania
Mingrelian affair