History: Atomic Bombing Of Hiroshima, Japan

At 11:01, a last minute break in the clouds over Nagasaki allowed Bockscar's bombardier, Captain Kermit Beahan, to visually sight the target as ordered. The "Fat Man" weapon, containing a core of ~6.4 kg (14.1 lbs.) of plutonium-239, was dropped over the city's industrial valley. It exploded 43 seconds later at 469 meters (1,540 ft) above the ground exactly halfway between the Mitsubishi Steel and Arms Works in the south and the Mitsubishi-Urakami Ordnance Works (Torpedo Works) in the north. This was nearly 3 kilometers (2 mi) northwest of the planned hypocenter; the blast was confined to the Urakami Valley and a major portion of the city was protected by the intervening hills. The resulting explosion had a blast yield equivalent to 21 kilotons of TNT (88 TJ). The explosion generated heat estimated at 3,900 degrees Celsius (4,200 K, 7,000 °F) and winds that were estimated at 1005 km/h (624 mph).
Casualty estimates for immediate deaths range from 40,000 to 75,000. Total deaths by the end of 1945 may have reached 80,000. At least eight known POWs died from the bombing and as many as 13 POWs may have died:
- One British Commonwealth citizen died in the bombing.
- Seven Dutch POWs (two names known) died in the bombing.