There are more ways than ever to listen to History Daily ad-free.

Listen with Wondry Plus in the Wondry app.

As a member of NoisorPlus at noisor.com or in Apple Podcasts,

or you can get all of History Daily plus other fantastic history podcasts at IntoH30 a.m. on July 16th, 1945, at the Alamigordo bombing range in rural New Mexico.

41-year-old Dr. Robert Oppenheimer strikes a match, lights a cigarette, peers out at the pale sky from behind the concrete walls of a bunker.

Even though it's early, Robert and dozens of fellow scientists have been in position for hours.

Robert is nervous, smoking cigarette after cigarette as he waits for a break in the weather.

Persistent rain has threatened to delay the

culmination of years of work, but the clouds have finally cleared, and a little over five miles away,

the first ever atomic bomb is about to explode. America has been embroiled in World War II

for more than three years. Nazi Germany surrendered two months ago,

but their Japanese allies continue the fight.

So if this atomic bomb works,

many in the U.S. government believe it could finally bring Japanese resistance to an end.

Robert puts out his cigarette and checks his pocket watch

as the last few seconds ticked down before detonation.

Through a narrow slit in the bunker wall, he watches the horizon.

Then, as the countdown reaches zero, a silent, bright flash signals that the bomb has been detonated.

After a few seconds, a fiery ball swells into the sky.

And then the sound of the explosion hits, growing louder and louder, like a storm rolling in.

The scientists and observers in the bunker applaud and shake hands.

They've been working on the bomb for years, and they're relieved that the test seems to have been a success.

...