From the Associated Press:WASHINGTON (AP) - U.S. and Russian officials announced agreement Monday on how to safely dispose of 34 metric tons of Russian weapons-grade plutonium, overcoming a major hurdle in a joint nuclear nonproliferation effort that at times has been close to falling apart.First, let's do some math:1 metric ton = 1,000 kilograms = 2,200 lbs. Approximately 22 lbs. of fissile plutonium is required for one fission (not thermonuclear) "bare" warhead weapon. (34 x 2,200)/22 = enough "stuff" for about 3,400 sizeable bangs.(For additional information on the amount of fissile material required for various types and designs of weapons, as well as a brief discussion of the nuclear reactions associated with reactors and weapons, see this.)Preferred by nuclear states worldwide for its rapid fission rate, the 94Pu239 isotope of plutonium has a half-life of around 24,000 years.  (94 is the number of protons in the nucleus and...(Read Full Post)