The largest, most powerful nuclear weapon ever detonated. Developed by the Soviet Union, the bomb was originally designed to have a yield of about 100 megatons of TNT; however that was reduced by half in order to limit the amount of nuclear fallout that would result.This is equivalent to ten times the amount of all the explosives used in World War II
Approximately 97% of the total energy resulted from fusion alone as such, it was one of the "cleanest" nuclear bombs ever created, generating a very low amount of fallout relative to its yield.
The fireball touched the ground, reached nearly as high as the altitude of the release plane, and was seen and felt 1,000 km away. The heat from the explosion could have caused third degree burns 100 km away from ground zero. The subsequent mushroom cloud was about 60 km high (nearly seven times higher than Mount Everest) and 30–40 km wide. The explosion could be seen and felt in Finland, even breaking windows there
Atmospheric focusing caused blast damage up to 1,000 km away. The seismic shock created by the detonation was measurable even on its third passage around the Earth. Its Richter magnitude was about 5 to 5.25