Hiroshima-Nagasaki
An interactive geospatial exploration of the atomic bombings of Hiroshima and Nagasaki in August 1945. Reconstructs the hypocenters, comparative weapon yields, and concentric damage blast radii across the Japanese urban landscape.
Target Hypocenters & Peace Memorials
4 Locations • Hiroshima & Nagasaki, JapanThe Atomic Bombings of Japan (August 1945)
In August 1945, during the closing days of World War II, the United States dropped two atomic bombs over the Japanese cities of Hiroshima and Nagasaki. These operations, developed under the secretive Manhattan Project, marked the first and only instances of nuclear weapons used in warfare.
On August 6 at 08:15 JST, the B-29 bomber Enola Gay released Little Boy over Hiroshima's flat river delta, killing an estimated 140,000 residents by December 1945. Three days later, on August 9 at 11:02 JST, the B-29 Bockscar released Fat Man over Nagasaki's Urakami Valley, killing another 74,000. On August 15, Emperor Hirohito announced Japan's unconditional surrender, formally ending the Second World War.
First nuclear weapon deployed in armed conflict. Detonated 580 meters directly above Shima Hospital, triggering a catastrophic blast wave and massive firestorm that engulfed 11 km² of the city.
Fired a hollow subcritical uranium-235 projectile into a target cylinder. Only approximately 1.4% of the 64 kg payload underwent nuclear fission. Ground temperature reached 3,000°C–4,000°C within milliseconds.
Second wartime atomic detonation. Diverted from secondary target Kokura due to smoke cover, the plutonium weapon exploded over the Urakami industrial valley, devastating factories and residential districts.
Utilized a 6.2 kg delta-phase plutonium core surrounded by high-explosive lenses generating symmetrical inward shockwaves. The steep surrounding Urakami mountains channeled the shockwave north-south while partially shielding the historic harbor.
Located only 160 meters from the hypocenter, the former Prefectural Industrial Promotion Hall was one of the few structures whose vertical brick skeleton withstood the downward blast. Preserved as a monument to international peace.
A quiet park marking the exact hypocenter where the plutonium bomb burst overhead. Features the black granite cenotaph, the iconic 10-meter Peace Statue, and remnants of the destroyed Urakami Cathedral.