Re: Today in History
Also; in the category of "near misses" here's what DIDN'T happen:
On February 26, 1942, a few months after his return from Copenhagen, Heisenberg delivered a lecture at the House of German Research in which he had the following to say about element 94—plutonium:
"As soon as such a machine [reactor] is on operation, the question of how to obtain explosive material, according to an idea of von Weizsacker, takes a new turn. In the transmutation of the uranium in the machine, a new substance comes into existence, element 94, which very probably—just like 235 92U [uranium 235—the fissionable isotope]—is an explosive of equally unimaginable force. This substance is much easier to obtain from uranium than 235 92U, however, since it can be separated from uranium by chemical means."
None of this did he tell Bohr. We can only conjecture what might have happened in the German program if Heisenberg had been able to make a functioning nuclear reactor capable of producing plutonium.
Whew!