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Powering Curiosity; Exploring New Horizons - DOE's MMRTG

by Mary Schorn on Thu, August 09, 2012



DOE's RTG is doing it again. The Department's Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) is providing continuous power to the Mars rover Curiosity.  This radioactive power source is "essentially a nuclear battery that will operate the rover’s instruments, robotic arm, wheels, computers and radio. It is fueled with plutonium-238 that gives off heat as it naturally decays. No moving parts are required to convert this heat into electricity."1

The MMRTG "can go farther, travel to more places, and power and heat a larger and more capable scientific payload compared to the solar power alternative NASA studied. The radioisotope power system gives Curiosity the potential to be the longest-operating, farthest-traveling, most productive Mars surface mission in history." 1

With the Curiosity safely on Mars, it begins its mission to explore and investigate "whether conditions have been favorable for microbial life and [to] preserve clues it finds in the rocks. Curiosity will analyze dozens of samples drilled from rocks or scooped from the ground as it explores with greater range than any previous Mars rover."1

"For 50 years, radioisotope power sources have safely and reliably fueled dozens of U.S. missions to explore seven planets in the solar system, including the [current] New Horizons mission to Pluto as well as Apollo, Voyager, Galileo and Cassini missions. Radioisotope power systems have a record for reliability and longevity unmatched by any other NASA spacecraft power system."1

The New Horizons spacecraft is about half way between Earth and Pluto with an expected "flight past the icy planet and its moons in July 2015.  After 10 years and more than 3 billion miles, on a historic voyage that has already taken it over the storms and around the moons of Jupiter, New Horizons will shed light on new kinds of worlds we've only just discovered on the outskirts of the solar system."2

"For the [New Horizons] mission, the Department of Energy developed and delivered a ... RTG.  This ‘space battery’ provides an uninterrupted and reliable source of heat and electricity in remote and harsh environments such as deep space.  The RTG will provide power and heat for many years to the New Horizons spacecraft and its on-board scientific equipment through the radioactive decay of nuclear material.  Heat generated by the radioactive decay of plutonium-238 is converted into electricity by solid-state thermoelectrics."3

With its RTG, DOE continues to provide critical support to United States and NASA space exploration.  Read more about DOE's RTGs at DOE R&D Accomplishments RTG - History, the Curiosity, and New Horizons.


1 Edited excerpts from Mars Science Laboratory, Idaho National Laboratory (INL)

2 Edited excerpt from New Horizons Halfway to Pluto, (NASA)

3Edited excerpt from DOE Technology Helps NASA Seek "New Horizons"  (DOE)

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