It's been 74 years since Hiroshima — the moment the US deployed the most powerful weapon known to man

US Army via Hiroshima Peace Memorial MuseumA mushroom cloud billows into the sky about an hour after an atomic bomb was dropped on Hiroshima, Japan.
  • August 6, is the 74th anniversary of the use of the first atomic bomb, dropped by the US on the Japanese city of Hiroshima.
  • 5-ton nuclear bomb, named “Little Boy,” fell for 44.4 seconds before detonating, ultimately killing 140,000 people and destroying 90% of the city.
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On August 6, 1945, at 8:15 a.m. local time, the world entered the atomic age.

The Enola Gay, a B-29 Superfortress bomber, dropped the most powerful weapon then known to man over Hiroshima.

The southern Japanese city was “an important army depot and port of embarkation,” but its location and population also appealed to US officials who wanted to showcase their new weapon’s destructive power.

Tuesday is the 74th anniversary of the bombing of Hiroshima, ordered by President Harry Truman in the final days of the war.

Hiroshima bombing gifPlay GIFYouTube/Amanda Macias/Business InsiderBird’s-eye-view footage of the ‘Little Boy’ attack.

In 2016, just a few months before the 71st anniversary, then-President Barack Obama became the first sitting president to visit the city – a trip to, in his words, “ponder a terrible force unleashed in a not-so-distant past.”

President Donald Trump, then a presidential candidate, was critical of Obama’s remarks.

The 5-ton nuclear bomb, named “Little Boy,” emerged from the Einstein-inspiredManhattan Project. The Enola Gay released it some 30,000 feet above the city, and the bomb fell for 44.4 seconds before detonating in a blast that would ultimately kill 140,000 people and destroy 90% of the city.

Three days later, the US dropped another bomb farther south, on the Japanese city of Nagasaki. That blast killed about 40,000 people instantly – thousands more would die of radiation poisoning.

Japan announced its surrender to Allied forces on August 15. On September 2, Japanese leaders signed the formal instrument of surrender aboard the USS Missouri, anchored in Tokyo Bay, formally ending World War II.

Hiroshima japanAPA huge expanse of ruins left from the explosion of the atomic bomb on Hiroshima, August 6, 1945.

Amanda Macias composed an earlier version of this post

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