On the morning of July 16, 1945, a young man named Jack Aeby snapped one of history’s most important and famous photographs: the only color picture of the first test of the atom bomb. Aeby was a 21-year-old amateur photographer. He was working as a technician on the Manhattan Project in Los Alamos, when he was granted permission to photograph a top-secret test, code named Trinity.

Recorded in Honolulu, HI. Premiered July 15, 2005, on All Things Considered.

Atomic History Timeline

September 1, 1939
Germany invades Poland: beginning of WWII.

September 23, 1942
The U.S. begins its effort to develop a nuclear weapon. This is code-named the “Manhattan Project,” and Colonel Leslie Groves is put in charge.

December 7, 1941
Japanese bomb Pearl Harbor.

December 8, 1941
U.S. enters WWII.

November 1942
Los Alamos, New Mexico selected as bomb development site, and J. Robert Oppenheimer is made director. Listen to newsreel [MP3, 506 KB].

May 5, 1943
Japan becomes the primary target for any future atomic bomb, according to the Military Policy Committee of the Manhattan Project.

May 8, 1945
Nazi Germany surrenders to the Allies.

July 16, 1945
The first atomic bomb is exploded at 5:29 AM Mountain War Time in the New Mexico desert. This is known as the “Trinity Test.” Listen to newsreel [MP3, 506 KB].

July 21, 1945
President Truman authorizes use of atomic bombs.

July 26, 1945
The U.S., Great Britain, and China issue the Potsdam Declaration, calling for the complete surrender of Japan. Listen to newsreel [MP3, 300 KB].

August 6, 1945
The atomic bomb, nicknamed “Little Boy,” is dropped on Hiroshima, Japan.

August 9, 1945
A second atomic bomb, nicknamed “Fat Man,” is dropped on Nagasaki, Japan.

August 14, 1945
Japan surrenders.

Information for time-line courtesy of the Los Alamos National Laboratory and the Los Alamos Historical Museum.

Trinity Scientists’ Oral Histories

Hans Bethe

Hans Bethe joined the team of scientists at Los Alamos in the summer of 1942. He was put in charge of organizing the theoretical division of the project. Mr. Bethe was a recent immigrant from Germany, whose family had escaped the Nazis.

We were terribly devoted to the project. We were convinced that it could be done. We had done lots of experiments in the experimental nuclear division showing that fission occurs immediately. We had done a lot of experiments on the implosion, which looked all right, but if it had not worked we would have tried again and we certainly would have kept at it, and we certainly would have dropped the bomb on Hiroshima.

I think everybody, after the test, felt he had made history and we were aware this would [be] world history from now on. We felt very accomplished. We felt we had done our job and we went on waiting for the actual drop on Japan.

I believed then and believe even more today, that the use of the atomic bomb, in that particular case was not only justified, but necessary. On the other hand ten years later it was totally different. Both the United States and the Soviet Union had hundreds, and then thousands of nuclear weapons, and so if a war had broken out between these two superpowers nuclear weapons would have been used from the beginning. They would not have been used to finish a war, but to start a war. And that makes all the difference.

Phillip Morrison

Scientists had been working at Los Alamos for over two years when Phillip Morrison arrived in August of 1944. Using models, he worked on measuring the reactivity of the bomb core. He rode in the car that carried the core of the bomb to the Trinity test site, and watched the explosion from Base Camp. After the bombs were dropped on Hiroshima and Nagasaki, Mr. Morrison traveled to Japan as a public relations liaison, and to measure the radioactivity on the ground.

It was a cool desert morning, the sun had not quite come up, the air was still, it had that curious chill of a hot place, which is the coolest hour of the day. And suddenly on that cold background the heat of the sun came to me before the sun rose. It was the heat of the bomb…not the light…but the heat was the first thing that I could feel: as though the sun had suddenly risen. But that was an unforgettable experience, because what you feel, I think, is deeper in the memory than what you just see. And so the notion that it was…some way, in the most elementary human way, competitive with the full sun, that was the time I got the sense of the power of the bomb more than anything else. It was unforgettable.

I think it opened the door to a dreadful corridor down which we never finally went, despite being very close to it. I always felt one small nuclear war was all that anyone could tolerate. We can’t have a second one. I think the main thing I want to say is it has to stop, and its not stopping yet.

Edward Teller

Edward Teller, a European immigrant, arrived at Los Alamos in 1942. There, he worked on calculating the power of a nuclear fission reaction. Mr. Teller witnessed the Trinity explosion with a group of fellow scientists gathered ten miles from the test site.

For minus 30-seconds on we heard nothing. That was an eternity and I was sure that there has been a failure. Then there appeared a very small point of light, and my first impression was, I very distinctly remember, “Is that all?” I started to see the point rising and spreading…[and] by that time I knew it was big. Then I was impressed. We knew that in a short time this would be used and it would be the real thing.

The bomb was dropped, and we saw the effects. I at once had a strong feeling of regret. Even today, I believe had we dropped the first bomb at an altitude of 30-thousand feet over Tokyo Bay that 10-million Japanese would have seen it and heard the thunderclash, including the emperor; probably it would have ended the war without a single person being hurt. And had that happened, we today would not be afraid of radioactivity. We today, would be much more reasonable about the simple fact that we ought to have the strengths, but we ought to be very careful before using it.

Oral histories courtesy of John Bass at the Los Alamos National Laboratory.

Aeby’s color photo of the Trinity explosion on Wikipedia.

Video stills of the Trinity explosion, taken by Berlyn Brixner, the government’s official videographer

This documentary comes from Sound Portraits Productions, a mission-driven independent production company that was created by Dave Isay in 1994. Sound Portraits was the predecessor to StoryCorps and was dedicated to telling stories that brought neglected American voices to a national audience.