Cobalt bomb

A cobalt bomb is a 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 in a radio program by physicist Leó Szilárd on February 26, 1950. His intent was not to propose that such a weapon be built, but to show that nuclear weapon technology would soon reach the point where it could end human life on Earth, a doomsday device. Such "salted" weapons were requested by the U.S. Air Force and seriously investigated, but not deployed. In the 1964 edition of the U.S. Department of Defense book The Effects of Nuclear Weapons, a new section titled radiological warfare clarified the "Doomsday device" issue.

The Russian Federation has allegedly developed cobalt warheads for use with their System-6 nuclear torpedoes. However many commentators doubt that this is a real project, and see it as more likely to be a staged leak to intimidate the US. Amongst other comments on it, Edward Moore Geist wrote a paper in which he says that "Russian decision makers would have little confidence that these areas would be in the intended locations" and Russian military experts are cited as saying that "Robotic torpedo shown could have other purposes, such as delivering deep-sea equipment or installing surveillance devices."

The Operation Antler/Round 1 test by the British at the Tadje site in the Maralinga range in Australia on September 14, 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. The triple "taiga" nuclear salvo test, as part of the preliminary March 1971 Pechora–Kama Canal project, produced relatively high amounts of Co-60 from the steel that surrounded the Taiga devices, with this fusion generated neutron activation product being responsible for about half of the gamma dose now (2011) at the test site. This high percentage contribution is largely because the devices did not rely much at all on fission reactions and thus the quantity of gamma emitting cesium-137 fallout, is therefore comparatively low. Photosynthesizing vegetation exists all around the lake that was formed.

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