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Your linked site for some reason doesn't include fallout by default, nor does it seem to factor casualties from it. Turn on fallout + surface burst, and a 100MT bomb's deadly fallout range goes from the center of France (where the label is on their map) to the center of Germany and I suspect that's an extreme underestimation, especially the conic they give.

It's also possible that the NYTimes is conflating facts by accident. Your demo link only accounts for single big-blast effects but the way you optimize damage with nukes is lots of smaller bombs, often in a single bomb - MIRV is one name for this. The reason is pretty simple. We approximate the explosive range as a sphere and the volume of that sphere is proportional to the cube (^1/3) of the yield.

So if you increase the yield by 10x you only increase the explosive radius by something like 2.15x. On the other hand, detonate 10 bombs side by side and you increase the radius by 10x. This not only maximizes damage, but also works to further nullify any sort of anti-missile defense. And 100MT would be well more than enough to obliterate France.

You can also kind of intuit this by thinking about 100MT means. That's 100,000,000 TONS of TNT explosive capacity. That's about 1.5 tons of TNT for each and every person in France. That's just a stupidly massive absurd amount of destruction.

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05 19 hours ago | parent | next [-]

> detonate 10 bombs side by side and you increase the radius by 10x

By 10**.5~=3.2x

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lostlogin 17 hours ago | parent [-]

It’s not very tidy phrasing, but I think the meaning is that 10 detonations next to each other (blast diameters touching) is 10x the diameter?

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somenameforme 16 hours ago | parent [-]

He's right. You'd want to arrange them in a square for comparable coverage so it'd be sqrt(10) = ~3.2.

It feels somehow nice and correct that an effort to reduce a 3d problem (basically a lot of our boom goes up or down, which is not necessary in most cases) to a 2d one changes it from a gain of x^(1/3) to x^(1/2).

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lostlogin 15 hours ago | parent [-]

The OP presumably meant a line of blasts though? That would possibly be the least efficient orientation after blasting the same spot 10x.

	▲	TheOtherHobbes 13 hours ago \| parent [-]
		Depends on your goal, the nature of the target, and how much damage you want to do. At one extreme there are precision attacks in silos and airfields. At the other are genocide attacks where you want to kill as many people as possible and leave as much of the land uninhabitable for as long as possible. In the middle are precision strategic attacks, where you want to leave infrastructure and buildings so you have the option to invade and take over.

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pfdietz 11 hours ago | parent | prev [-]

The fallout from a bomb is going to depend on its design.

In a typical thermonuclear bomb, most of the yield is still from fission, so there are lots of fission products. The purpose of the fusion is to generate neutrons to more thoroughly fission the fissionable material.

However, it's possible to design thermonuclear bombs with greatly reduced fission fraction. The extreme example of that were the Ripple tests, which the US conducted shortly before atmospheric tests were banned. These involve a secondary without a fission "spark plug", where carefully tailored implosion cause the density/temperature at the core of the secondary to reach conditions for fusion ignition, in a way very similar to how inertial confinement fusion reactors are imagined to work. The most extreme of these has been reported to derive 99% of its yield from fusion reactions. If the neutrons from these are absorbed in something with low activation the fallout could be greatly reduced.