Radioisotope Power Systems
Space nuclear power to explore the deepest, dustiest, darkest, and most distant regions of our solar system and beyond.
TODAY
Active Missions
Years in Service at NASA
Active Missions
Voyager 1
47 Years in Space
Voyager 2
47 Years in Space
New Horizons
18 Years in Space
Curiosity
12 Years on Mars
Perseverance
3 Years on Mars
RPS — short for radioisotope power systems — are a type of nuclear energy technology that uses heat to produce electric power for operating spacecraft systems and science instruments. That heat is produced by the natural radioactive decay of plutonium-238.
Voyager Mission
The Voyagers owe their ability to operate at such great distances from the Sun to their nuclear electric power sources, which provide the electrical power they need to function.
Dr. Edward Stone (1936-2024)
Voyager Project Scientist
Power to Explore writing contest
Perseverance Pays Off for Student Challenge Winners
Power to Explore
The winners of the 2024 Power to Explore Student Essay contest (from left to right) Aadya Karthik, Raine Lin, and Thomas Liu.
Credits: NASA/Rachel Zimmerman-Brachman
NASA Moon to Mars Architecture Art Challenge
This art challenge is looking for creative, artistic images to represent NASA's Moon to Mars Architecture, the agency's roadmap for crewed exploration of deep space. If you can create engaging artwork that depicts the exploration segments described below, you could win a portion of a $10,000 prize.
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Why Radioisotope Power Systems?
01From a Source of Heat Comes Power to Explore
RPS provide electricity and heat that can enable spacecraft to undertake scientific missions to environments beyond the capabilities of solar power, chemical batteries and fuel cells.
02A Critical Technology
RPS offer the key advantage of operating continuously over long-duration space missions, largely independent of changes in sunlight, temperature, charged particle radiation, or surface conditions like thick clouds or dust. Some of the excess heat produced by RPS can be used to enable spacecraft systems to operate in extremely cold environments.
03A Legacy of Exploration
RPS have enabled NASA's exploration of the solar system since the Apollo era of the late 1960s. Five radioisotope power systems powered missions are currently active.
