Tsar Bomba(s) 1080p ᴴᴰ Novaya Zemlya Russia equal to about 58 megatons of TNT [Mt] (240 PJ)

Tsar Bomba(s) 1080p ᴴᴰ Novaya Zemlya Russia equal to about 58 megatons of TNT [Mt] (240 PJ); The initial three-stage design (coded A620EN, not tested) was capable of yielding approximately 100 Mt (420 PJ) through fast fission, 3,000 times the size of the Hiroshima and Nagasaki bombs, but it was thought that it would have caused too much nuclear fallout, and the aircraft delivering the bomb would not have had enough time to escape the explosion. To limit the amount of fallout, the third stage and possibly the second stage had a lead tamper instead of a uranium-238 fusion tamper (which greatly amplifies the reaction by fissioning uranium atoms with fast neutrons from the fusion reaction). This eliminated fast fission by the fusion-stage neutrons so that approximately 97% of the total yield resulted from thermonuclear 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). There was a strong incentive for this modification since most of the fallout from a test of the bomb would likely have descended on populated Soviet territory. Although simplistic fireball calculations predicted the fireball would hit the ground, the bomb’s own shock wave reflected back and prevented this. The 8-kilometre-wide (5.0 mi) fireball reached nearly as high as the altitude of the release plane and was visible at almost 1,000 km (620 mi) away from where it ascended. The mushroom cloud was about 67 km (42 mi) high (over seven times the height of Mount Everest), which meant that the cloud was above the stratosphere and well inside the mesosphere when it peaked. The cap of the mushroom cloud had a peak width of 95 km (59 mi) and its base was 40 km (25 mi) wide.