Sustainability

Afraid of nuclear power?

In ’97, the Cassini probe was launched, and this was accompanied by a great controversy regarding the danger of radioactive contamination, that could have taken place during the launch or during the probe’s passage near the Earth. In fact the probe was put in orbit by a launch vehicle, Titan IV which had a load of 33 kg of plutonium-238 (the largest amount of plutonium ever taken into space) and it was fed by radioisotope thermoelectric generators (RTG). These generators do not have atomic reactors, they simply exploit the heat produced by the radioactive decay of a small amount of plutonium to produce electric current. Plutonium is a highly toxic element, it is so toxic that for humans, less than one millionth of a gram is considered a carcinogen dose – Furthermore, its half-life is only 88 years, that makes it 300 times more toxic than plutonium 239 that is used in the construction of nuclear devices. At the time of the mentioned Cassini-Huygens mission, which had the task of taking a probe into orbit around Saturn and letting another fall on its moon Titan, NASA rapidly pointed out that the RTG and the containers for the combustible were designed to overcome any type of accident and remain intact, even in case of accidents of a catastrophic nature. With regard to the plutonium, it was stacked in containers made of a special heat-resistant ceramic, with the property of breaking instead of pulverizing into particles that could be inhaled, and subdivided into different modules, each having different layers to protect them from heat and any impact. However, in the past accidents of a certain gravity have occurred various times. Six Soviet missions that carried radioactive material on board, failed, and in the case of NASA, 3 out of 24. On 21 April 1964, the satellite SNAP-9a disintegrated, falling back onto the Earth. According to a Report of the Organization for Economic Co-operation and Development in 1989, debris from the satellite are present in all the continents and at all latitudes.