The cobalt bomb is a theoretical modification of weapons of mass destruction, which leads to high degrees of radioactive contamination and contamination of the terrain with a relatively small explosion force. Cobalt bomb refers to radiological weapons, in which ionizing radiation acts as a damaging factor . At the same time, because of the relative weakness of the explosion, almost all the infrastructure, buildings, structures and buildings remain intact.
A cobalt bomb is a nuclear munition, the shell of which is not made from uranium-238, but from cobalt-59. During detonation, the shell is irradiated with a powerful neutron flux, which leads to the transmutation of cobalt-59 into the cobalt-60 isotope. Its half-life is a little more than 5 years. As a result of the beta decay of this nuclide, nickel-60 forms in the active state, which after a while passes into the base state.
The activity of cobalt-60 weighing one gram is estimated at 1130 Ci. To fully infect the entire surface of the planet with radiation at the level of a gram / square kilometer of cobalt-60, about 510 tons are needed. In general, the explosion of such a bomb can infect the terrain for almost 50 years. Such long terms leave little chance for the population to survive the infection even in bunkers.
It is believed that the cobalt bomb was never created, so it is not in the arsenal of any country. A small amount of this element was used in one of the British nuclear weapons tests for radiochemical markers.
The most terrible way to use a cobalt bomb is to blast it at high altitude, somewhat away from the enemy's territory, depending on the weather conditions. In this case, the goal is to radioactive fallout over the enemy's territory, which theoretically can destroy all life on it.
The very idea of this bomb was invented by physicist Leo Sylard, who made the assumption that an arsenal of cobalt bombs can destroy the entire population of the planet. Cobalt was chosen due to the fact that with neutron activation it gives a very strong and prolonged radioactive contamination. It is possible to use other elements that form isotopes with an even longer half-life when creating such an ammunition, but their activity is clearly inadequate. There are also short-lived isotopes compared to cobalt-60, such as sodium-24, zinc-65 and gold-198, but because of their rather rapid decay, part of the population can survive contamination of the terrain in bunkers.