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Similar physics - it's a fusion bomb, hence the low residual radiation. Wikipedia claims, BTW, that the energy released by this explosion was about 16.6 times a

by m0zg 6y ago

Similar physics - it's a fusion bomb, hence the low residual radiation. Wikipedia claims, BTW, that the energy released by this explosion was about 16.6 times all explosive energy released in WW2, and about 1/10th of all energy released by all nuclear testing.

lmilcin 6y ago
There exists no purely fusion bomb. All thermonuclear bombs are lighted by a fission stage and bomb of such size would definitely have more than one.
- m0zg 6y ago
  Yes, but the initial nuclear charge is comparatively small (1.5MT), and dispersed over a large area, since the bomb is detonated pretty high above the ground. To my knowledge there is only one such charge in this bomb. If its yield weren't limited to 50MT, there'd be two such stages. Andrei Sakharov suggested not using U238, replacing it with some passive material in the secondary module. The yield was limited because if it weren't, there _would_ be a lot of radioactive contamination, and the fireball would touch the ground, exacerbating the problem. https://ru.wikipedia.org/wiki/%D0%A6%D0%B0%D1%80%D1%8C-%D0%B1%D0%BE%D0%BC%D0%B1%D0%B0#%D0%98%D0%B7%D0%B4%D0%B5%D0%BB%D0%B8%D0%B5_602 https://ru.wikipedia.org/wiki/%D0%A6%D0%B0%D1%80%D1%8C-%D0%B... https://www.atomic-energy.ru/files/books/Ukroschenie%20yadra%20(2005).pdf https://www.atomic-energy.ru/files/books/Ukroschenie%20yadra...
  - DennisP 6y ago
    Wow, I never realized Tsar Bomba was scaled down. Wiki link says with U238 it would have yielded over 100MT. Also confirms that it was a very clean bomb, with over 97% of the energy coming from fusion.
    - lmilcin 6y ago
      97% energy coming from fusion is in no way proof of this being clean bomb. 3% from fission is still many times more than Hiroshima or Nagasaki bomb. We also don't know how much fissile material there was (and how much was dispersed in environment). Because the bomb was detonated high up there wouldn't be hotspots on the ground but the release was still there, dispersed for all humanity for decades to come. Calling the bomb clean would be like calling somebody's vomit clean because it was diluted in large amount of water and then sprayed on all walls so there are no large concentrations of it.
      - m0zg 6y ago
        Well, that lake your city draws their drinking water from? I guarantee someone vomited, peed and shat into it. The issue is the concentration. Remember that because this was 4KM above ground, the resulting fallout was spread over tens of thousands of square kilometers.
      - DennisP 6y ago
        Everything's relative. Of course it generated more radioactivity than Hiroshima's measly fifteen kilotons, but for a fifty megaton bomb it was pretty darn clean.
      - sudosysgen 6y ago
        Sure, but that radiation is dispersed over much, much greater distances and you need less radiation to give the effect intended. The end result is that the explosion zone is not nearly as radioactive as either Hiroshima or Nagasaki. Also, there is vomit all over the pavements and walls of your city. Just in low concentrations.

by m0zg 6y ago

lmilcin 6y ago

There exists no purely fusion bomb. All thermonuclear bombs are lighted by a fission stage and bomb of such size would definitely have more than one.

m0zg 6y ago
Yes, but the initial nuclear charge is comparatively small (1.5MT), and dispersed over a large area, since the bomb is detonated pretty high above the ground. To my knowledge there is only one such charge in this bomb. If its yield weren't limited to 50MT, there'd be two such stages. Andrei Sakharov suggested not using U238, replacing it with some passive material in the secondary module. The yield was limited because if it weren't, there _would_ be a lot of radioactive contamination, and the fireball would touch the ground, exacerbating the problem. https://ru.wikipedia.org/wiki/%D0%A6%D0%B0%D1%80%D1%8C-%D0%B1%D0%BE%D0%BC%D0%B1%D0%B0#%D0%98%D0%B7%D0%B4%D0%B5%D0%BB%D0%B8%D0%B5_602 https://ru.wikipedia.org/wiki/%D0%A6%D0%B0%D1%80%D1%8C-%D0%B... https://www.atomic-energy.ru/files/books/Ukroschenie%20yadra%20(2005).pdf https://www.atomic-energy.ru/files/books/Ukroschenie%20yadra...
- DennisP 6y ago
  Wow, I never realized Tsar Bomba was scaled down. Wiki link says with U238 it would have yielded over 100MT. Also confirms that it was a very clean bomb, with over 97% of the energy coming from fusion.
  - lmilcin 6y ago
    97% energy coming from fusion is in no way proof of this being clean bomb. 3% from fission is still many times more than Hiroshima or Nagasaki bomb. We also don't know how much fissile material there was (and how much was dispersed in environment). Because the bomb was detonated high up there wouldn't be hotspots on the ground but the release was still there, dispersed for all humanity for decades to come. Calling the bomb clean would be like calling somebody's vomit clean because it was diluted in large amount of water and then sprayed on all walls so there are no large concentrations of it.
    - m0zg 6y ago
      Well, that lake your city draws their drinking water from? I guarantee someone vomited, peed and shat into it. The issue is the concentration. Remember that because this was 4KM above ground, the resulting fallout was spread over tens of thousands of square kilometers.
    - DennisP 6y ago
      Everything's relative. Of course it generated more radioactivity than Hiroshima's measly fifteen kilotons, but for a fifty megaton bomb it was pretty darn clean.
    - sudosysgen 6y ago
      Sure, but that radiation is dispersed over much, much greater distances and you need less radiation to give the effect intended. The end result is that the explosion zone is not nearly as radioactive as either Hiroshima or Nagasaki. Also, there is vomit all over the pavements and walls of your city. Just in low concentrations.