Radioisotope power systems in space missions: Overview of the safety aspects and recommendations for the European safety case

Nuclear power sources can offer a potential solution to some of the challenges related to space applications, such as the use of photovoltaics in opaque atmospheres or in a dark environment for a long time. Thanks to their high energy densities, certain isotopes are capable of generating considerable amounts of heat for long periods of time, independently of insolation levels; this heat can then be converted into electrical power, or used to keep suitable temperatures inside the spacecraft.