5 ms·
One of the main differences is what the tamper is made out of (the casing). You need a material that is reflective to the X-rays used to compress the fusion fue
by Teknoman117 5y ago
One of the main differences is what the tamper is made out of (the casing). You need a material that is reflective to the X-rays used to compress the fusion fuel. In Castle Bravo, this was made out of uranium-238, in the Tsar bomb, it was made from lead. Using uranium boosted the power output by about 2x, at the expense of making the bombs far, far dirtier. The extreme heat and the high neutron radiation from the primary (a fission device) detonating would cause the uranium to decay into more unstable isotopes (U-235, Pu-239, etc.) which would then fission themselves.
The ideology at the time was that a larger blast was more important, since at the time nuclear weapons were still to be dropped by bombers (No ICBMs for another decade). You wanted the bomb to take out the target even if you couldn't quite reach it.
The Soviets estimated that using the same technique would have produced a yield of 100 Mt, but for testing, lead was used to limit the fallout to something they deemed manageable.
- corty 5y agoThere are multiple effects, tamper material is only one of them. Ground bursts also increase the overall amount and concentration of fallout: First, with the explosion closer to ground, more neutrons can reach the ground and activate material there, producing radioactive isotopes from previously harmless earth. The "fireball" is a shell of expanding lower-density plasma which doesn't dampen neutrons as much as gas (especially water vapour) in non-plasma air. So that fireball touching ground produces more activated elements increasing overall fallout. Second, all newly created active elements and more fusion/fission products get bound to ground particles like dust, coral or water droplets if the explosion stirs up more of that. Those particles are larger and heavier, producing a more concentrated fallout closer to ground zero, whereas unbound products would be dispersed higher in the atmosphere without producing too much of a distinctive fallout pattern.
- LorenPechtel 5y agoAnd note that when the particles are small they stay up longer--and a lot of the hottest stuff decays before it ever reaches the ground.
- fifilura 5y agoThe most evil invention here is the cobalt bomb. https://en.wikipedia.org/wiki/Cobalt_bomb https://en.wikipedia.org/wiki/Cobalt_bomb A theme for example in Nevil Shute's On the Beach. Where people in Australia spent their last days waiting for the cloud to eventually reach them.
- lgl 5y agoThe doomsday device on Stanley Kubrick's Dr Strangelove is also a fictional cobalt type bomb, or as quoted [0] in the movie: "If you take, say, fifty H-bombs in the hundred megaton range and jacket them with Cobalt-Thorium G, when they are exploded they will produce a doomsday shroud. A lethal cloud of radioactivity which will encircle the earth for ninety-three years!" It's a fantastic movie that I highly recommend to anybody that hasn't seen it yet. [0] https://en.wikipedia.org/wiki/Cobalt_bomb#In_popular_culture https://en.wikipedia.org/wiki/Cobalt_bomb#In_popular_culture
- Teknoman117 5y agoAnother evil intention I can recall along this thread is the "neutron" bomb. The idea being, produce a nuclear weapon that has a extreme radiation pulse during detonation but generates no long lived nuclides. Detonate over enemy territory, everyone dies from radiation sickness from the detonation, then you can move in and all the infrastructure is still in place. Not much development ever took place, considering such a thing could only ever be an offensive/invasion weapon.