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Everyday science

Little Boy was a little girl

By Hamish Johnston

Sorry for the delay on this entry, but the 15 December issue of the New Yorker just landed on our doormat about a week late.

In that issue there is an article by David Samuels about an American truck driver called John Coster-Mullen, who has spent the past 15 years or so trying to understand how Little Boy worked.

Little Boy was the atomic bomb that destroyed much of Hiroshima in 1945 — and not surprisingly, its design has remained a secret.

Coster-Mullen, who is 60, described his quest as “nuclear archeology,” and doesn’t seem too concerned that his book, Atom Bombs: The Top Secret Inside Story of Little Boy and Fat Man could be of interest to those intent on wreaking mayhem. Defending Coster-Mullen, Samuels writes “Surely, hostile powers could easily obtain the kind of information that Coster-Mullen has acquired, however painstakingly, in his spare time”.

Indeed, after reading the New Yorker piece, I was left with the chilling thought that just about anyone with about 60 kilograms of uranium-235 could build a bomb like Little Boy. And the key to success, according to Coster-Mullen, is realising that the bomb was “female” in design rather than “male” — something that previous historians had missed completely.

The New Yorker also has a slide show called Secrets of the Bomb

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