WHY CAN PEOPLE LIVE IN HIROSHIMA AND NAGASAKI BUT NOT THE CHERNOBYL EXCLUSION ZONE?
Today, Hiroshima and Nagasaki are thriving cities inhabited by a total of 1.6 million people, and the background levels of radiation there are no different from elsewhere in the world. Meanwhile, scientists estimate that many areas within the immediate vicinity of the Chernobyl nuclear power plant, most within a 10km area, may be uninhabitable for hundreds to thousands of years. The main reason for the difference in outcomes is that Little Boy and Fat Man, the bombs that hit Hiroshima and Nagasaki, exploded at heights of around 450 to 600 metres, allowing the radioactivity to disperse soon after. Meanwhile, the bulk of the massive release of radioactive material in Chernobyl occurred at ground level. Another difference was the efficiency of fission reaction in the two bombs. Researchers estimate that just 1 per cent of the uranium carried by Little Boy and plutonium carried by
Fat Man actually detonated — only about 0.9kg. On the other hand, some 190 tonnes of fuel are thought to have been vaporised in the Chernobyl accident.