L'utilisation des radio-isotopes pour la production d'énergie électrique a bord des engins spatiaux

Comparing the characteristics of the primary energy sources available on board of space vehicles, it is shown that radioisotopes exhibit definite potentialities for missions of intermediate to long duration, involving but moderate power levels.
After a survey of the suitable conversion systems, the authors delineate the different criteria a radioisotopic source must meet before it can be applied to the production of auxillary electrical energy on board of space vehicles. On this basis, eleven isotopes have been selected for their best fitted characteristics ; the latter are summarized in tabular form and then separately discussed for each of the considered radioelements.
The principal advantages of radioisotopic sources are to be found in their unfailingness, their higher specific powers and energetic capacities, and their independence towards environmental influences.
Their drawbacks are chiefly associated to safety and cost problems, as well as to the decrease of the delivered power in course of time.
As a conclusion, it is put forward that an accelerated development of radioisotopic generators is most desirable in connection with the present planning of space missions and the more important items on which this effort should be directed are briefly listed.