Dropping the First Atomic Bomb
At 2:45 A.M. local time, the Enola Gay, a B-29 bomber loaded with an atomic bomb, took off from the US air base on Tinian Island in the western
Pacific. Six and a half hours later, at 8:15 A.M. Japan time, the bomb was dropped and it exploded a minute later at an estimated altitude of 580 +-
20 meters over central Hiroshima.
The Hiroshima Bomb
Size: length - 3 meters, diameter - 0.7 meters.
Weight: 4 tons.
Nuclear material: Uranium 235.
Energy released: equivalent to 12.5 kilotons of TNT.
Code name: "Little Boy".
Initial Explosive Conditions
Maximum temperature at burst point: several million degrees centigrade. A fireball of 15-meters radius formed in 0.1 millisecond, with a temperature
of 300,000 degrees centigrade, and expanded to its huge maximum size in one second. The top of the atomic cloud reached an altitude of 17,000 meters.
Radioactive debris was deposited by "black rain" that fell heavily for over an hour over a wide area.
Demaging Effects of the Atomic Bomb
Thermal Hear. Intense thermal heat emitted by the fireball caused severe burns and loss of eyesight. Thermal burns of bare skin occurred as far as 3.5
kilometers from ground zero (directly below the burst point). Most people exposed to thermal rays within 1-kilometer radius of ground zero died. Tile
and glass melted; all combustible materials were consumed.
Blast. An atomic explosion causes an enormous shock wave followed instanteneously by a rapid expansion of air called the blast; these represent
roughtly half the explosion's released energy. Maximum wind pressure of the blast: 35 tons per square meter. Maximum wind velocity: 440 meters per
second. Wooden houses within 2.3 kilometers of ground zero collapsed. Concrete buildings near ground zero (thus hit by the blast from above) had
ceilings crushed and windows and doors blown off. Many people were trapped under fallen strunctures and burned to death.
Radiation. People exposure within 500 meters of ground zero was fatal. People exposed at distances of 3 to 5 kilometers later showed symptoms of
aftereffects, including radiation-induced cancers.
Acute symptoms. Symptoms appearing in the first four months were called acute. Besides burns and wounds, they included: general malaise, fatigue,
headaches, loss of appetite, nausea, vomiting, diarrhea, fever, abnormally low white blood cell count, bloody discharge, anemia, loss of hair.
Aftereffects. Prolonged injuries were associated with aftereffects. The most serious in this category were: keloids (massive scar tissue on burned
areas), cataracts, leukemia and other cancers.
Population. The estimated pre-bomb population was 300,000 to 400,000. Because official documents were burned, the exact population is uncertain.
Deaths. With an uncertain population figure, the death toll could only be estimated. According to data submitted to the United Nations by Hiroshima
City in 1976, the death count reached 140,000 (plus or minus 10,000) by the end of December, 1945.
Health Card Holders. Persons qualifying for treatment under the A-bomb Victims Medical Care law of 1957 received Health Cards; holders as of March 31,
1990, numbered 352,550.
Nagasaki. The atomic bomb dropped on Nagasaki exploded at 11:02 A.M. on August 9. Using plutonium with an explosive power of 20 kilotons of
TNT-equivalent, it left an estimated 70,000 dead by the end of 1945, although both population and the deaths are uncertain.
If we had not dropped the bomb Americans would be eating fishhead soup if even that.
All's fair in love and war, too bad we didn't drop more!