Alex Wellerstein writes: On 6 August 1945, the first atomic bomb to be used in anger detonated over the city of Hiroshima, Japan. Three days later, it was Nagasaki’s turn. That was the last such attack. Despite the worst of the cold war’s close calls, like the Cuban missile crisis, no other nuclear weapons have ever been used outside of testing. Seven decades later, it is worth asking: could it happen again? Here are five possible nuclear use scenarios. [Continue reading…]

The Washington Post: At 8:15 a.m., Little Boy dropped. The fall to the burst altitude of 1,968 feet lasted 43 seconds. At that moment, Little Boy was moving faster than the speed of sound.

The bomb exploded with a blinding flash above the center of the city.

The burst temperature was estimated at more than 1 million degrees Celsius. It ignited the surrounding air, forming a fireball about 900 feet in diameter.

Thirty seconds after the explosion, the Enola Gay circled to get a better look at what was happening. The city itself was engulfed in black smoke and, although the bomber was flying at 30,000 feet, the mushroom cloud had already risen above it, eventually reaching almost 56,000 feet.

The bomb, which exploded near its target over the center of the city, leveled two square miles. A firestorm incinerated everything within 6,000 feet of ground zero.

The blast wave shattered windows within 10 miles and was felt as far away as 37 miles. More than two-thirds of Hiroshima’s buildings were demolished. The heat ignited fires as far as two miles from ground zero.

The nuclear fireball and the ensuing blast killed 60,000 to 80,000 people in the time it has taken you to read this paragraph, and mortally wounded or seriously injured an estimated 50,000 more. [Continue reading…]