The Atomic Bombings of Hiroshima and Nagasaki

Surveillance image of Hiroshima prior to August 6, 1945.

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Hiroshima August 6, 1945

Times are in Tinian Time Unless Otherwise Noted, One Hour Ahead of Hiroshima

0245 Early morning on Tinian, the B-29 Superfortress Enola Gay and her crew of 12 lift off with the uranium bomb Little Boy aboard. The Enola Gay is accompanied by two observation aircraft, The Great Artiste and Necessary Evil.

0320 Little Boy is armed.

0730 Enola Gay Captain Paul Tibbets announces to the crew: “We are carrying the world’s first atomic bomb”.

Hiroshima, August 6, 1945.

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0809 Air raid sirens begin in Hiroshima.

0912 Enola Gay bombardier Thomas Ferebee takes control of the aircraft as the bombing run begins.

0914:17 Hiroshima’s Aioi Bridge, the target point, comes into view. A 60-second timer commences.

0915:15 (8:15 am in Hiroshima) Ferebee announces “Bomb away” as Little Boy is released from 31,060 feet (9467m).

0916:02 (8:16:02 am in Hiroshima) After falling from the Enola Gay for 43 seconds, the Little Boy atomic bomb detonates 1,968 feet above Hiroshima, 550 feet (167.64 m) from the Aioi Bridge. Nuclear fission begins in 0.15 microseconds.

The aftermath of the atomic bombing of Hiroshima.

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0916:03 (8:16:03 am in Hiroshima, one second after detonation). The fireball reaches maximum size, 900 feet (274.32m) in diameter. The mushroom cloud begins to form. As temperatures on the ground reach 7,000 degrees Fahrenheit (3871 Celsius), buildings melt and fuse together, human and animal tissue is vaporized. The blast wave travels at 984 miles per hour (1583.59 kph) in all directions, demolishing over two-thirds of Hiroshima’s buildings in a massive, expanding firestorm. Eighty thousand people are instantly killed or grievously wounded. Over 100,000 more will die from the bomb’s effects in the coming months.

1055 The U.S. intercepts a Japanese message: “a violent, large special-type bomb, giving the appearance of magnesium.”

1458 The Enola Gay lands at Tinian. The mission has lasted twelve hours.

1500 Tokyo news agencies report an attack on Hiroshima. Very few details are given.

Hiroshima, five days after the bombing.

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Nagasaki after the atomic bombing.

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Nagasaki August 9, 1945

Times are in Tinian Time Unless Otherwise Noted, One Hour Ahead of Nagasaki

0347 The B-29 Superfortress Bockscar lifts off from Tinian with the plutonium bomb Fat Man aboard. The target is the Japanese city of Kokura.

0351 and 0353 Support planes the Great Artiste and Big Stink lift off from Tinian. Two weather-spotting aircraft, the Enola Gay and Laggin’ Dragon are already airborne.

0400 Cmdr. Fred Ashworth arms Fat Man atomic bomb.

1044 Bockscar arrives at Kokura. Haze makes it too difficult to locate the drop point.

1132 Major Charles Sweeney, Bockscar’s pilot, makes the decision to turn for the secondary target, Nagasaki, 95 miles south of Kokura.

1158 Upon arrival over Nagasaki, cloud cover allows for only one drop point, several miles from the intended target. Bombardier Kermit Beahan releases the Fat Man atomic bomb.

1202 (11:02am in Nagasaki) Fat Man explodes 1,650 feet (502.92m) above the city. Between 40,000-75,000 people die instantly. The bomb creates a blast radius one mile wide (1609.34m) . The geography of Nagasaki prevents destruction on the same scale as Hiroshima, yet nearly half the city is obliterated.

2230 All aircraft return to Tinian.

Bibliography

• “Hiroshima and Nagasaki Bombing Timeline”, Atomic Heritage Foundation, accessed August 4, 2020, https://www.atomicheritage.org/history/hiroshima-and-nagasaki-bombing-timeline