Friday, August 06, 2010

Fat Man and Little Boy


Remember when we were kids and in school they told us all about how the Bomb was going to kill us all, in fact, wipe out all life on planet earth down to the microbial level?

Remember when "If you love this planet" was sent round to all the high schools and we would go on ban the bomb rallies as part of our civics classes?

When "every fifteen minute period could be your last"?

They told us that the worst thing that could possibly happen was the Bomb. The end of the world, and all that.

We were told that atom bombs were "radioactive" (though I note that no one ever actually bothered to define it...we thought microwave ovens were radioactive too) and where they fell, no one and nothing could live for twenty or thirty or fifty thousand years after...

The early bombs were pretty "dirty" it is true. They caused a lot of long-term medical problems in the people who were in the vicinity and survived the first blast.

how many people live in Hiroshima today?

Just askin...

Wiki: "By 1955, the city's population had returned to pre-war levels."



Alex said...

Yeah, but aren't today's nuclear weapons more potent than Fat Man or Little Boy by an exponential factor?

Zach said...

The correct term is "by orders of magnitude" and yes, they are -- at least, if you're measuring blast power. Fat Man / Little Boy were measured in kilotons (of TNT-equivalent); modern weapons are measured in megatons. (I think that's "kilotonnes" and "megatonnes" for the Brits and Canadians in the audience...)

No idea how that translates to differences in generated fallout, although I'm sure there are some fine declassified reports from the government available for anyone who wants to dig and do the math.

BillyHW said...

I'm not an expert, but I think I read on the internet somewhere sometime waybackwhen that modern thermonuclear weapons have less fallout because they generate most of their explosive power from a fusion reaction with the fission reaction only providing the trigger.

BillyHW said...

Not sure though.