The question is that if they drop atomic bomb the radiation from some radioactive isotopes has a really long half-life, and not sure if you can create a bomb only with isotopes who have short half-life. I am definitely not an expert and now I am curious if someone managed to achieve that.

For perspective, and don't tell me that dropping nuclear bombs over civilians was the necessary evil to do during WWII. Because if it was, how would you explain this:

The atomic bomb that detonated over Hiroshima used Uranium-235, while the Nagasaki bomb had Plutonium-239. The half-life of U-235 is 700 million years, while that of Pu-239 is 24,000 years. In other words, once on the ground, they will be there for a very long time.

[–] Orygin@sh.itjust.works 4 points 9 months ago* (last edited 9 months ago) (1 children)

These atomic weapons are not used anymore. We use thermonuclear fusion weapons which do not irradiate the area as much: Fusion, unlike fission, is relatively "clean"—it releases energy but no harmful radioactive products or large amounts of nuclear fallout. https://en.m.wikipedia.org/wiki/Thermonuclear_weapon#:~:text=Fusion%2C%20unlike%20fission%2C%20is%20relatively,of%20fission%20products%20and%20fallout.

Edit: I am a bit wrong, a fusion bomb by itself is relatively clean, but these damn bastards make them with extra fissile material for extra boom. Making it still quite radioactive when exploding

[–] Quereller@lemmy.one 3 points 9 months ago

To start a fusion reaction you need the energy of a fission bomb. (At least for bombs and stuff)