On the morning of August 6, 1945, the world’s first deployed atomic bomb was dropped by a U.S. aircraft over the Japanese city Hiroshima. A desperate but devastating attempt to bring the relentless Second World War to a close, the act destroyed 90% of the city. Sixty-four kilograms (141 pounds) of uranium-235 were loaded into the “Little Boy” bomb, resulting in the deaths of an estimated 66,000 individuals, and injuring a further 69,000.

Just three days later, following refusal to relinquish, Nagasaki suffered a similar fate, this time to 6.2 kilograms (13.7 pounds) of plutonium-239. Named "Fat Man," the bomb was the second and final time that nuclear weapons were used during warfare. Although estimated figures of casualties vary widely for both events, in part due to discrepancies over the pre-bombing city populations, it is thought that the second bombing racked up a smaller yet still significant death toll of 39,000, alongside 25,000 injuries.

Blasting through windows, reducing buildings to piles of rubble and ash, exposing thousands to deadly radiation, triggering fires and general destruction, it’s hard to truly imagine the consequences of these war-ending bombings. But to mark the 70th anniversary of the Hiroshima event and prevent it from fading from our minds, Kuang Keng Kuek Ser and colleagues at Public Radio International have developed an interactive application that allows you to visualize the destruction Little Boy would cause today.

^{Public Radio International}

Using data from several reports, the application creates an estimate of the damage and fatalities that would result if the Hiroshima atomic bomb hit a modern day city. For example, if detonated above London, U.K., damage would ensue within a 12-mile radius of ground zero. For those 0.5 miles around the target spot, highlighted by the dark red bullseye, an estimated 90% of people would die as a result of fire and destructive blast pressures. Up to a mile around ground zero, all buildings and other city features would be destroyed.

Taking this one step further, Stevens Institute of Technology nuclear historian Alex Wellerstein has come up with a similar idea, but his simulator “NukeMap” allows you to select different bombs and provides a more detailed explanation of the estimated effects on today’s cities.

[H/T: Washington Post]