At around 8 a.m. on August 6, 1945, the sky over Hiroshima changed forever. The U.S. bomber Enola Gay dropped a devastating atomic bomb called “Little Boy,” which weighed 9,700 pounds. The bomb detonated 600 meters above the city, creating a fireball with temperatures reaching 7,000°C. It also released shockwaves that traveled faster than the speed of sound. Hiroshima, a city with a population of approximately 350,000, predominantly composed of civilians, became the epicenter of the atomic age.

The Bomb Behind the Blast

• “Little Boy” was a uranium-based gun-type bomb.
• Developed under the top-secret Manhattan Project, it was the first nuclear weapon used in warfare.
• The bomb’s 15-kiloton yield equaled the power of 15,000 tons of TNT.

The U.S. aimed to force Japan’s surrender and end World War II. But the method was unlike any the world had seen.

Destruction on a New Scale

• The blast flattened nearly everything within a 2-kilometer radius.
• Fires spread instantly, fed by wooden homes and dry summer air.
• Black rain fell afterward—radioactive, sticky, and deadly.

By year’s end, the death toll reached an estimated 140,000. Half died instantly. Many others succumbed to burns, radiation sickness, and injuries. Most were civilians.

Voices of Survival

Each year, Japan commemorates the survivors, known as hibakusha, at the Hiroshima Peace Memorial Park. The Atomic Bomb Dome is a part of the Peace Garden and is the only structure that remained standing, serving as a haunting silhouette and a reminder of that fateful morning.

Why Hiroshima?

Hiroshima was a key military hub and transportation center. Its relatively untouched condition made it a prime target to showcase the bomb’s power. U.S. officials believed a swift, shocking blow might end the war without invading Japan.

But critics later asked: was it necessary?

Legacy of the Blast

• On August 9, a second bomb—”Fat Man”—fell on Nagasaki.
• Japan surrendered on August 15, marking the end of World War II.

The Hiroshima and Nagasaki bombings remain the only use of nuclear weapons in war.