“A one-thousand-megaton device exploded in outer space could devastate an area the size of six western states.” Caldicott, Helen. Nuclear Madness. New York: Bantam Books, 1980, p.65.
NUCLEAR FACT: “As the weapon yield increases by a factor of ten, the danger radius increases by a factor of approximately two.”
First of all, there would be no blast effect at all on the ground. Except for the EMP effect killing the power grid, people on the ground would not know that a weapon was detonated at all. Secondly, there are no one-thousand-megaton (MT) weapons or even a one-hundred-MT weapon. It is not that they could not be built, but we cannot change the laws of physics, which dictate that, as the weapon yield increases by a factor of ten, the danger radius increases by a factor of approximately two. So, a one-hundred-MT weapon would not have a danger radius of ten times a ten-MT weapon but only twice. A one-thousand-MT weapon would have a danger radius of approximately four times that of a ten-MT weapon or eight times that of a one-MT weapon. It would make no economic sense to produce a one-hundred-MT weapon that would inflict 1/100th the damage that one hundred one-MT weapons would inflict and yet cost the same amount of money and hit one hundred different targets. For this reason, the trend by all nations is toward smaller kiloton weapons. More accurate smaller weapons in the kiloton range are replacing the large megaton weapons of the Soviets. Thirdly, except for a very small breeze (approx. 25 mph), a one-thousand-MT weapon detonated in outer space would produce no blast effect on the ground at all.11