History Today: When Oppenheimer tested the first atomic bomb  

FP Explainers July 16, 2025, 09:05:07 IST

The first atomic bomb, nicknamed ‘The Gadget’, was launched at the Trinity test site in Alamogordo, New Mexico, on July 16, 1945. Led by physicist J Robert Oppenheimer, the launch ushered in a new era - the nuclear age. The test was part of the Manhattan Project, which brought together some of the greatest scientific minds of the time, including Enrico Fermi, Richard Feynman and Niels Bohr

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World's first atomic bomb was detonated in New Mexico on July 16, 1945. Image Courtesy: nps.gov
World's first atomic bomb was detonated in New Mexico on July 16, 1945. Image Courtesy: nps.gov

The world entered the nuclear age on July 16, 1945, with the detonation of the first atomic bomb, which was tested in the New Mexico desert. Code-named Trinity, it was part of the Manhattan Project, a massive scientific and military effort by the United States to develop nuclear weapons during World War II.

If you are a history geek who loves to learn about important events from the past, Firstpost Explainers’ ongoing series, History Today , will be your one-stop destination to explore key events.

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On this day in 1951, JD Salinger’s iconic novel, The Catcher in the Rye, was published. The book introduced the world to the unforgettable teenage protagonist, Holden Caulfield.

Here is all that took place on this day across the world.

The first atomic bomb exploded

One of most important events of the 20th Century took place on July 16, 1945. The first atomic bomb was successfully tested by the United States in Alamogordo, New Mexico. And with this, the world entered the nuclear age.

The bomb, nicknamed “The Gadget,” used plutonium-239 and was detonated at 5:29 am. The explosion created a blinding flash, a fireball that reached temperatures hotter than the surface of the sun and a mushroom cloud that rose over seven miles (11 kilometres) into the sky. It produced an energy equivalent of about 21 kilotons of TNT.

A man sits next to The Gadget, the nuclear device created by scientists to test the world’s atomic bomb, at the Trinity Site in Alamogordo, New Mexico. Wikimedia Commons

Led by physicist J Robert Oppenheimer, the Manhattan Project brought together some of the greatest scientific minds of the time, including Enrico Fermi, Richard Feynman and Niels Bohr. The successful test confirmed that nuclear fission could be weaponised, changing the course of history.

After witnessing the explosion, Oppenheimer famously quoted the Bhagavad Gita, “Now I am become Death, the destroyer of worlds.”

Just three weeks later, the US dropped atomic bombs on Hiroshima on August 6 and Nagasaki on August 9, leading to Japan’s surrender and the end of World War II. The Trinity test not only marked the dawn of nuclear warfare but also triggered decades of arms races, Cold War tensions and ethical debates about the use of such destructive technology.

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Catcher in the Rye published

JD Salinger’s only full-length novel, The Catcher in the Rye, was published by Little, Brown and Company on this day in 1951. With the launch of the book, the world was introduced to the unforgettable teenage protagonist, Holden Caulfield.

Set in post-World War II America, the novel follows Holden over the course of three days in New York City after being expelled from prep school. Disillusioned by the “phoniness” of the adult world and struggling with grief over the death of his younger brother, Holden narrates his journey in a raw, confessional tone that was both controversial and groundbreaking at the time.

JD Salinger’s classic novel, which gave life to Holden Caulfield. File image/AP

While initial reviews were mixed, the book quickly gained popularity among young readers and became a bestseller. Its honest portrayal of teenage alienation, mental health, and rebellion struck a chord with postwar youth and sparked widespread debate.

Salinger, who became famously reclusive after the novel’s publication, never allowed a film adaptation and published little afterward. Yet his lone novel became a literary icon and has sold over 65 million copies worldwide.

This Day, That Year

  • Chicago officially opened its Millennium Park on this day in 2004.

  • In 1979, Saddam Hussein became president of Iraq.

  • Apollo 11 lifted off from Nasa’s John F Kennedy Space Center in Florida on this day in 1969.

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