NationalTerrorAlert.com
The Pu-239 weighs 10.5 kg and is 10.1 cm across. It doesn’t take much more than a single critical mass to cause significant explosions ranging from 10-20 tons. These types of weapons can also be as big as two footlockers.
The warhead of a suitcase nuke or suitcase bomb consists of a tube with two pieces of uranium, which, when rammed together, would cause a blast. Some sort of firing unit and a device that would need to be decoded to cause detonation may be included in the “suitcase.”
Another portable weapon is a “backpack” bomb. The Soviet nuclear backpack system was made in the 1960s for use against NATO targets in time of war and consists of three “coffee can-sized” aluminum canisters in a bag. All three must be connected to make a single unit in order to explode. The detonator is about 6 inches long. It has a 3-to-5 kiloton yield, depending on the efficiency of the explosion. It’s kept powered during storage by a battery line connected to the canisters.
The largest known variants of these devices has a yield of 3-5 Kilotons.
The Hiroshima Blast, although not accurately recorded, is believed to be around 15 Kilotons.
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A nuclear blast would be a terrible, terrible thing. Of that, there is no argument. Several of them simultaneously would be an enormous blow.
I certainly hope we don't see this one come true.
