Thursday, August 6, 2009

August 6, 1945


Sixty four years ago today and atomic bomb as dropped on Hiroshima.

The bomb was released at 08:15 (Hiroshima time). The gravity bomb known as "Little Boy", a gun-type fission weapon with 60 kilograms of uranium-235, took 57 seconds to fall from the aircraft to the predetermined detonation height about 600 metres above the city.

Due to crosswind, it missed the aiming point, the Aioi Bridge, by almost 240 m and detonated directly over Shima Surgical Clinic.

It created a blast equivalent to about 13 kilotons of TNT. (The U-235 weapon was considered very inefficient, with only 1.38% of its material fissioning.)
The radius of total destruction was about 1.6 km, with resulting fires across 11 km2. Americans estimated that 12 km2 of the city were destroyed. Japanese officials determined that 69% of Hiroshima's buildings were destroyed and another 6–7% damaged.

70,000–80,000 people, or some 30% of the population of Hiroshima were killed immediately, and another 70,000 injured. Over 90% of the doctors and 93% of the nurses in Hiroshima were killed or injured; most had been in the downtown area which had been greatly damaged.

2 comments:

Bert said...

Yep, and it's a good thing it was dropped too. Had it not been dropped, and the Allies gone ahead with the Invasion of Japan, the resulting death toll would have been MUCH higher.

Cari said...

That is what gets me..... this was bad enough, and knowing the horrors of that, why do countries insist on having bigger bombs now.?