[PiriReis]

In July of 1945, the United States was in the final stages of developing a powerful and deadly new weapon - the Atomic Bomb. Here, Los Alamos director J. Robert Oppenheimer is seen in silhouette as he oversees final assembly of "The Gadget", the first nuclear device to be detonated, at the Trinity test site in New Mexico. 

The expanding fireball and shockwave of the Trinity test explosion, seen .025 seconds after detonation in the New Mexico desert on July 16, 1945.

Following the July 26 Potsdam Declaration, where Allies outlined the terms of surrender for Japan and promised "inevitable and complete destruction" of Japan if they failed to comply, preparations were secretly under way to make use of the newly-tested Atomic Bomb. Here, the first nuclear device to be used as a weapon, codenamed "Little Boy", rests on trailer cradle in a pit, ready for loading into the bomb bay of the "Enola Gay" in August of 1945.

On Monday, August 6, 1945, 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. Nearly 80,000 people are believed to have been killed immediately, with possibly another 60,000 survivors dying of injuries and radiation exposure by 1950.

A pall of smoke lingers over this scene of destruction in Hiroshima, Japan, on August 7, 1945, a day after the explosion of the atomic bomb. Nearly 80,000 people are believed to have been killed immediately, with possibly another 60,000 survivors dying of injuries and radiation exposure by 1950.

Aftermath of the nuclear bomb on Hiroshima

The searing heat from the nuclear explosion above Hiroshima scorched the roadway of this bridge across the Ota River, about a half a mile from the focal point of the bomb burst. The areas shielded by the concrete pillars and railings were left undamaged, creating permanent "shadows" on the bridge deck.

The shadow of a handle on a gasometer left an imprint after the August 6, 1945 atomic bomb explosion, two kilometers away from the hypocenter in Hiroshima. 

Only days after the bombing of Hiroshima, the second operational nuclear weapon was readied by the U.S. Called "Fat Man", the unit is seen being placed on a trailer cradle in August of 1945. When the Japanese still refused to surrender after Hiroshima, U.S. President Truman issued a statement saying in part "If they do not now accept our terms, they may expect a rain of ruin from the air, the like of which has never been seen on this earth."

"Fat Man" was dropped from the B-29 bomber Bockscar, detonating at 11:02 AM, at an altitude of about 1,650 feet (500 m) above Nagasaki. An estimated 39,000 people were killed outright by the bombing a further 25,000 were injured.

This picture made shortly after the August 9, 1945 atomic bombing, shows workers carrying away debris in a devastated area of Nagasaki, Japan. This picture obtained by the U.S. Army from files of Domei, the official Japanese news agency, was the first ground view of the nuclear destruction in Nagasaki.

The only recognizable structure remaining is a ruined Roman Catholic Cathedral in background on a destroyed hill, in Nagasaki, Japan in 1945.

Dr. Nagai, medical instructor and x-ray specialist at Nagasaki Hospital, a victim of atomic radiation caused by the nuclear bombing. A few days after this photo was made, Dr. Nagai passed away.

People walk through the charred ruins of Nagasaki, shortly after an atomic bomb destroyed much of the city. The explosion generated heat estimated at 3,900 degrees Celsius (4,200 K, 7,000 °F).

Dozens of F4U Corsair and F6F Hellcat fighter planes fly in formation over the USS Missouri, while the surrender ceremonies to end World War II take place aboard the U.S. Navy battleship, on September 2, 1945.

The scene aboard the battleship Missouri as the Japanese surrender documents were signed in Tokyo Bay, on September 2, 1945. Here, General Yoshijiro Umezu signs the Instrument of Surrender on behalf of the Armed Forces of Japan, Foreign Minister Mamoru Shigemitsu (behind him, in top hat) had earlier signed on behalf of the government. Both men were later tried and convicted of war crimes. Umezu died while in prison, Shigemitsu was paroled in 1950, and served in the Japanese government until his death in 1957.

A red globe representing the fireball above Hiroshima, at the Hiroshima Peace Memorial Museum