About Radioisotope Power Systems – Science@NASA
RPS offer several important benefits. They are compact, rugged and provide reliable power in harsh environments where solar arrays are not practical. For example, Saturn is about ten times farther from the sun than Earth, and the available sunlight there is only one hundredth, or one percent, of what we receive at Earth. At Pluto, the available sunlight is only six hundredths of a percent of the amount available at Earth. The ability to utilize radioisotope power is important for missions to these and other incredibly distant destinations, as the size of solar arrays required at such distances is impractically large with current technology.
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