How the Energy Department Is Powering NASA’s Soon-to-Launch Mars Rover

Building on a lesser-known, but decades-long history of pursuits enabling space travel, the Energy Department and several of its national labs play a part in NASA’s day-away mission to send the Perseverance rover to search for ancient life on Mars. 

The more-than $2 billion, roughly 2,260-pound rover, after several delays, is set to launch Thursday from Florida's Cape Canaveral Air Force Station, and embark on a months-long journey into the solar system to land at Mars' Jezero Crater in February. There, the wheeled “robotic scientist” will traverse the planet and use built-in instruments to hunt for signs of past microbial life, study the climate and much more. The advanced machine will also ferry the 4-pound Ingenuity Mars Helicopter to the red planet as part of a technology demonstration in support of NASA’s broader Artemis mission to send human explorers to Mars in the 2030s.

Perseverance will run on a nuclear power system built by Energy. It will be the first rover in more than three decades to use domestically-produced plutonium created in national labs, and the department also designed and built the vehicle’s SuperCam, which probes rocks and soils to uncover organic compounds that could be connected to past life.  

“I've seen NASA launches before, but this one is special from my point of view,” Energy’s Undersecretary for Science Paul Dabbar told Nextgov Tuesday, as he was preparing to head to Florida for Perseverance’s liftoff. “We support various things, but the amount of effort going into Perseverance by us as well as NASA is at the higher end.” 

Energy’s portfolio includes a range of space-centric efforts underway jointly with NASA that cover areas such as asteroid-watching for planetary defense, exploring particle physics and how the universe was made and imaging the universe in support of scientific discoveries. Dabbar also offered a glimpse into how the two agencies’ collaboration—and Energy’s role in outer-space—might evolve going forward.

“So ‘DOE’ is an acronym that we like to periodically rename what it stands for. Previously, Secretary [Rick] Perry used to refer to it as the ‘Department of Everything,’” Dabbar noted. “The latest derivation of that acronym could be the ‘Department of Exploration.’”

Powering Perseverance

For missions where probes, robotics and other space-exploring machines venture deep out into the solar system or require more power than solar panels can provide, Energy can design, manufacture and deliver to NASA a radioisotope thermoelectric generator, or RTG, to use as a power-source. The department has provided the space agency with such systems for missions dating back to Apollo in the 1960s. Now, heat that’s generated by the natural decay of plutonium-238 is converted by Perseverance’s multi-mission RTG into about 110 watts of electricity, according to Dabbar, which he said will keep the rover running optimally and “without any worries about sandstorms or cloud cover.”

National lab-led work underpinning the development and construction of the generator was threefold. As a note from Energy’s Assistant Secretary for the Office of Nuclear Energy details, Oak Ridge National Laboratory provided the system’s plutonium oxide heat source fuel and fuel cladding and Los Alamos National Laboratory manufactured the fuel by encapsulating the plutonium-238, which has a half-life of around 88 years. On top of assembling the unit, Idaho National Laboratory also delivered it to Florida for the launch. 

Notably, the rover will be the first of its kind—in more than 30 years—to be powered by domestically-produced plutonium formed within America’s national labs. In the late 1980s, U.S. production of plutonium for space exploration that was previously led by Energy ceased, and it wasn’t until 2011 that NASA began receiving funds from Congress to enable the department to resume U.S. domestic production for certain space applications. A report from the Government Accountability Office in 2017 warned that plutonium-238 was a “scarce” electricity resource, and recommended that Energy better address production challenges. Reflecting on those suggestions, Dabbar noted a science reactor that Oak Ridge uses to produce not only this isotope but others for a range of medical and scientific purposes has supported production capacity for the effort—as has additional funding Congress has supplied to national labs over the years. 

“In part, we're able to do this because of the enhanced support,” he said.

Energy’s release also confirms that Oak Ridge recently automated part of this production process, which helped insiders to inch “closer to NASA’s ultimate goal of 1.5 kilograms per year by 2026.”

The overall, Perseverance power-providing initiative fits into a broader strategy the department recently released to “regain global leadership in nuclear energy.” Dabbar added that rovers are getting larger and demanding more power with time, and the effort could possibly lead to a larger conversation with NASA about stronger RTGs that could potentially support the space agency’s plans to “go to the moon and never leave,” through Artemis. 

“Our engagement here is not only about being able to produce the RTG, but to produce it more efficiently at a larger scale, larger power needs, and ultimately continue that path,” toward future missions, Dabbar said.

More Than a Cam: a SuperCam 

Mounted on Perseverance will be a camera, laser and spectrometers—collectively constituting the rover’s “SuperCam”—to examine the chemical composition of rocks and soils on Mars and identify compounds that hold potential insights about ancient life on the planet. According to a summary of the tool, SuperCam can pinpoint “chemical and mineral makeup of targets as small as a pencil point from a distance of more than 20 feet.”

Dabbar said the instrument integrates remote Laser Induced Breakdown Spectroscopy capabilities to take a hard look at mineral compositions and traces of possible organic compounds on Earth’s neighbor. 

“This goes into the much, much broader topic of the possibility of ancient habitability, biology, on Mars—before the atmosphere degraded away and before much of the water disappeared,” Dabbar explained. “And so this is going to be … support for the cutting-edge science, and take a look at those soils and rocks to see if there was ancient life on Mars. That's, you know, pretty darn exciting in my book.”

Considered a souped up version of the ChemCam that’s presently aboard the Mars Curiosity rover, SuperCam’s mass incorporates a 12-pound, mast-mounted sensor head, body-mounted electronics that make up 10.6 pounds, and a half-pound calibration target. Dabbar highlighted that the SuperCam was “designed, built and tested” by Energy’s Los Alamos National Laboratory in New Mexico—and in partnership with the French space agency, Centre national d'études spatiales, or CNES.

“I think that's one interesting takeaway: space is very much about international collaboration,” Dabbar said. “Obviously the U.S. has been at the leadership of space since the Apollo program, but we very much want to work—and do work—with many other countries and partnerships and in particular with different components. And so working with the French Space Agency on SuperCam led by us at Los Alamos was very exciting.”

An Evolving Partnership

National labs are already at-work preparing another advanced nuclear power system for the Dragonfly rotorcraft lander mission intended to launch in 2026 and investigate Saturn’s largest moon.

And another component of the Perseverance mission involves drilling and collecting soil samples that could show signs of past life, so that they can potentially be packaged and shipped to Earth for human examination in a future mission that NASA and the European Space Agency are currently planning.

“And one of the things that we're talking with NASA about is you need very large X-ray machines to image the samples after you bring them back to Earth. And we're in conversations ... about using one of [Energy’s] national labs, where we have the brightest X-ray imagers in the world,” Dabbar noted.

Additionally, during his trip to Cape Canaveral for the rover’s launch, the undersecretary said he’ll also join “a full working session” through which Energy’s and NASA’s leadership teams will “review every interaction between the national labs” and the space agency. Topics will include the potential for quantum communications and satellites, mapping the Big Bang—and much more.

“We'll do a full survey and identify how we can push discovery even further in the universe together,” Dabbar said.