Curium is a synthetic radioactive element in the actinide series. It is a transuranic element, produced by bombarding plutonium with helium ions. Curium isotopes were considered as alternatives to plutonium-238, the most common fuel for radioisotope thermoelectric generators (often found in nuclear-powered spacecraft). However, it produces undesirable radiation products as it decays and thus requires more shielding. According to Los Alamos National Laboratory, curium can be obtained for $100/mg. The homologue of curium is gadolinium.
