In the early morning hours of July 16 1945, a truck driver in New Mexico reported that he saw the sun about to rise at 4 am. The sun decided it was too early, he said, so it went down again and came up an hour later.
[p206, Victor Weisskopf (1989) The Privilege of Being a Physicist].
What the truck driver had witnessed was the test of world’s first nuclear bomb, code-named Trinity. At a remote location in New Mexico, the explosion melted desert sand leaving a crater of radioactive glass over 300 m in diameter. Its blast smashed windows as distant as 120 miles away.
This historic event marked the successful outcome of a top-secret American Army project, started 3 years earlier in 1942. The scientists referred to their bomb – the first-ever nuclear bomb - as “the gadget”. Many of the talented scientists working on the Manhattan project later became famous – people like Hans Bethe, Neils Bohr, Enrico Fermi, Richard Feynman, Robert Oppenheimer, Isidor Rabi, and Edward Teller. The experience was life changing for many, see the story of Jo Rotblat for a detailed study of how one Manhattan Project scientist went on to receive the Nobel Peace Prize.
Developing the bomb meant pushing back frontiers in science and engineering. Solving challenging technical problems had motivated these scientists. But many of them were stunned by the explosive power of the weapon they had produced.
Hiroshima and Nagasaki - a watershed