The mushroom cloud became the image of ultimate destruction which the advancement of science had made available to man -- the latest in a long line of tools of war.
Today marks the 64th anniversary of the dropping of the bomb "Little Boy" from the B-29 bomber Enola Gay on the Japanese city of Hiroshima.
Shortly after 8:15 am, August 5, 1945, looking back at the growing "mushroom" cloud above Hiroshima. When a portion of the uranium in the bomb underwent fission, and was transformed instantly into an energy of about 15 kilotons of TNT (about 6.3 × 1013 joules), heating a massive fireball to a temperature of 3,980 C (7,200 F). The superheated air and smoke rapidly rose through the atmosphere like a giant bubble, dragging a column of smoke up with it. By the time this photo was made, smoke had billowed 20,000 feet above Hiroshima while smoke from the burst of the first atomic bomb had spread over 10,000 feet on the target at the base of the column. (U.S. National Archives)From yesterday's Boston Globe:
The U.S. B-29 Superfortress bomber "Enola Gay" took off from Tinian Island very early on the morning of August 6th, carrying a single 4,000 kg (8,900 lb) uranium bomb codenamed "Little Boy". At 8:15 am, Little Boy was dropped from 9,400 m (31,000 ft) above the city, freefalling for 57 seconds while a complicated series of fuse triggers looked for a target height of 600 m (2,000 ft) above the ground. At the moment of detonation, a small explosive initiated a super-critical mass in 64 kg (141 lbs) of uranium. Of that 64 kg, only .7 kg (1.5 lbs) underwent fission, and of that mass, only 600 milligrams was converted into energy - an explosive energy that seared everything within a few miles, flattened the city below with a massive shockwave, set off a raging firestorm and bathed every living thing in deadly radiation. Nearly 70,000 people are believed to have been killed immediately, with possibly another 70,000 survivors dying of injuries and radiation exposure by 1950.The article from the Boston Globe has some magnificent photos well worth viewing.
The classic little book Hiroshima by John Hersey is one of those must-reads for every age.
First published on August 31, 1946 when The New Yorker devoted an entire issue to telling of the effects of the atomic bomb dropped on Hiroshima, it
Follows the fate of six survivors and describes their experiences. The survivors were: Miss Toshiko Sasaki, a clerk in the personnel department of the East Asia Tin Works; Dr. Masakazy Fuji; Father Wilherlm Kleinsorge, a German priest of the Society of Jesus, the Rev. Kiyoshi Tanimoto, pastor of the Hiroshima Methodist Church, and a Mrs. Hatsuyo Nakimura, a tailor's widow and her three children.Forty years later John Hersey went back to Hiroshima in search of the people whose stories he had told and in 1985 the book was republished with a final chapter that provides his moving account of what he discovered.The New Yorker
Hersey's book will keep the human story of that horrific day in history alive for future generations. The first sentence illustrates the author's spare and poignant writing style.
AT EXACTLY fifteen minutes past eight in the morning, on August 6, 1945, Japanese time, at the moment when the atomic bomb flashed above Hiroshima, Miss Toshiko Sasaki, a clerk in the personnel department of the East Asia Tin Works, had just sat down at her place in the plant office and was turning her head to speak to the girl at the next desk.