Hiroshima: The moment the US deployed the most powerful weapon known to man

hiro

(US Army via Hiroshima Peace Memorial Museum)
A mushroom cloud billows into the sky about one hour after an atomic bomb was dropped by American B-29 bomber, the Enola Gay, detonating above Hiroshima, Japan.

On August 6, 1945 at exactly 8:15 a.m. (local time), the world entered the unprecedented atomic age with the deployment of the most powerful weapon known to man.

Nearly 71 years since US President Harry S. Truman's decision to unleash approximately 12,500 tons of TNT over the Japanese city of Hiroshima, US President Barack Obama will become the first sitting president to visit the city.

Released from B-29 Superfortress Enola Gay and born from the Einstein-inspired Manhattan Project, the 5-ton atomic bomb named "Little Boy" fell for 44.4 seconds before killing 140,000 people and destroying 90% of the city.

Three days later, the US dropped another bomb on the Japanese city of Nagasaki, killing about 40,000 people instantly; thousands more would die of radiation poisoning.

Eight days later, Japan informally surrendered to the Allied forces, effectively ending World War II.

hiroshima japan

(AP)
A huge expanse of ruins left the explosion of the atomic bomb on Aug. 6, 1945 in Hiroshima. 140,000 people died because of the disastrous explosion.

NOW WATCH: President Obama calls for the end of nuclear weapons at Hiroshima

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