It was on this day in 1945 that the first atomic bomb was exploded at 5:30 a.m., 120 miles south of Albuquerque, New Mexico. It was the end result of the Manhattan Project, which had started in 1939. The bomb contained a ball of plutonium about the size of a baseball, surrounded by a ring of uranium and a series of detonators.
One of the physicists who was there that day said: “We were lying there, very tense, in the early dawn, and there were just a few streaks of gold in the east; you could see your neighbor very dimly. … Suddenly, there was an enormous flash of light, the brightest light I have ever seen … it bored its way right through you. It was a vision which was seen with more than the eye. It was seen to last forever. … There was an enormous ball of fire which grew and grew and it rolled as it grew; it went up into the air, in yellow flashes and into scarlet and green. It looked menacing. It seemed to come toward one.”
(From the Writer’s Almanac)