Cobalt Bomb

A cobalt bomb is a theoretical type of "salted bomb": a nuclear weapon designed to produce enhanced amounts of radioactive fallout, intended to contaminate a large area with radioactive material. The concept of a cobalt bomb was originally described on February 26, 1950 by physicist Leó Szilárd, who suggested on a radio program that an arsenal of cobalt bombs would be capable of destroying all human life on Earth (though his conclusions are disputed).

As far as is publicly known, no cobalt bombs have ever been built. The Operation Antler/Round 1 test by the British at the Tadje site in the Maralinga range in Australia on 14 September 1957 tested a bomb using cobalt pellets as a radiochemical tracer for estimating yield. This was considered a failure and the experiment was not repeated.