The Day That Changed the World Forever

By Abby Pokraka, Program Assistant

On July 16, 1945, scientists conducted the Trinity Test. The world would never be the same.

That test ushered in a new era dominated by the most immensely destructive weapons ever created. It led to a Cold War which saw, at its peak, more than 70,000 nuclear weapons on the planet. It changed the way leaders negotiate, and their considerations for entering into military conflict. The Trinity Test’s countless effects continue to shape the world today, so it is important to remember and reflect on the day that changed the course of history.

Nine months prior to the beginning of World War II, German radiochemists Otto Hahn and Fritz Strassmann accidentally discovered nuclear fission. As news of this spread to France, the Soviet Union, the United Kingdom and the United States, physicists rushed to demonstrate nuclear fission in their laboratories, as well.

In the summer of 1939, a group of physicists, including Leo Szilard, wrote a letter for Albert Einstein to sign and deliver to President Franklin D. Roosevelt. The letter described how a nuclear chain reaction could lead to the construction of bombs of enormous destructive power. Having been the first to discover nuclear fission, there was a fear that Nazi Germany was quickly building the foundation for an atomic weapons program, and the race to build the first atomic bomb began.

In the United States, the research and development efforts to create an atomic bomb was called The Manhattan Project. The first controlled nuclear chain reaction took place under the grandstands at Stagg Field, University of Chicago. With continued research, the nuclear facility at Los Alamos was ready to test an atomic weapon by early summer 1945.

Preparation for the Trinity Test faced many setbacks. As the Gadget (the nickname for the bomb) was raised into position, the bomb became partially unhinged and began dangerously swaying from the 100-foot tower. Workers froze at the possibility of the bomb accidentally falling and detonating, but eventually the device was righted and brought to the top of the tower without further incident.

Due to unsuccessful practice tests without nuclear materials, scientists began an informal pool, betting on the likelihood the test would produce an explosion. J. Robert Oppenheimer, Director of the Los Alamos Laboratory and father of the atomic bomb, actually bet George Kistiakowsky, a physical chemist working at the site, that the test would fail.

As the test date approached, many scientists grew increasingly anxious. Edward Teller, a theoretical physicist, and the man who would later become the father of the hydrogen bomb, feared an atomic explosion would accidentally ignite the atmosphere, and cause global destruction.

The night before the Trinity test, wind and rain worried the scientists so much that Oppenheimer decided someone needed to sit with the bomb until the test occurred. Donald Hornig, the explosives expert at the site, sat with the live bomb during a violent lightning storm, and contemplated what the “monster” beside him would do to the world if it worked. The test was scheduled for July 16, 1945 at 4 a.m., but due to thunderstorms, the scientists waited. They were prepared to cancel the test when the weather began to improve, pushing the test to 5:29 a.m.

When the atomic bomb was finally detonated, the tower that held it was vaporized and the ground around the tower turned to trinitite, a green glassy substance forged from the heat of the test. Immediately following the flash of the explosion, a huge shock and heat wave went searing across the desert. A fireball rose high into the air, with a second, thinner column rising and flattening into a mushroom shape. That mushroom cloud became etched onto our collective consciousness—a symbol of both our capacity for scientific achievement and our capacity for destruction.

Immediate reactions to the successful test were joy, surprise and relief. Hans Bethe, director of the Theoretical Division at Los Alamos, was completely blinded for almost 30 seconds from looking directly at the explosion. George Kistiakowsky, standing more than five miles away from the test site, was knocked to the ground from the blast. He jumped back up, turned to Oppenheimer, and said “Oppie, you owe me ten dollars.”

After the feeling of success wore off, the creators began to reflect on what they just created. The most chilling reaction was that of Oppenheimer who years later stated “I remembered the line from the Hindu scripture, the Bhagavad Gita. […] ‘Now I am become Death, the destroyer of worlds.’ I suppose we all thought that, one way or another.” Many of the Manhattan Project scientists were haunted by their role in creating the atomic bomb for the rest of their lives.  

Immediately in the wake of the test, Szilard morally objected to the use of an atomic bomb in warfare and drafted a petition for President Truman demanding the Japanese be warned before the atomic bomb was used. Szilard’s letter was never received by the President and the 12 signatories were criticized by Manhattan Project leadership.

On August 6, 1945, the United States dropped an atomic bomb on Hiroshima. Three days later, the United States dropped another — the kind tested at Trinity — on Nagasaki. Debate over this action continues today, as do the effects of this momentous test.

Thankfully, nuclear tests have all but ended—only North Korea has tested in this century. Knowledge of the dangers posed by explosive nuclear testing resulted in the creation of agreements like the Limited Test Ban Treaty and the Comprehensive Test Ban Treaty. Still, the ill effects of nuclear testing persist today.

Cancer clusters and other health problems can be seen near test sites in the Marshall Islands, French Polynesia, Kazakhstan, Australia and beyond. They can also be found here in the United States. Wind carried radioactive elements across borders and continents, contaminating the Earth. Today, humans carry radioactive substances in their bones, and tests that occurred decades ago have increased the risk of cancer.

In addition to these effects on living organisms, nuclear testing may have brought the world into a new geological period — the Anthropocene Epoch — which refers to an age of widespread human influence over the planet. A group of scientists argue that we moved away from the Holocene Epoch when we began testing nuclear weapons. Radioactive isotopes from atomic weapon tests have been embedded in sediments, ice and glacial rock, becoming part of the geologic record. Not only has nuclear testing affected the future of human life, it has created a new chapter in the history of our planet.

With the whispers and rumors about possibility of resumed nuclear tests by the United States and others, we should look to the past and learn from our actions. Given the concerns and reservations of so many of the scientists who enabled the Trinity test, and the physical proof we have of the damage caused by nuclear testing, it is difficult to understand why anyone would want to repeat history. Seventy-four years after Trinity, it’s not hard to imagine that many of the scientists who made that test happen would be cheering on a new generation of scientists and policymakers working to end explosive testing once and for all.