April 21, 2023, 3:19PMNuclear NewsSal Oriti, Ernestina Wozniak, and Max Yang The multimission radioisotope thermoelectric generator for NASA’s Mars 2020 Perseverance rover is tested at NASA’s Kennedy Space Center in 2020. The choice of an MMRTG as the rover’s power system gave mission planners significantly more flexibility in selecting the rover’s landing site and in planning its surface operations. (Photo: NASA)
Under the Radioisotope Power Systems Program, NASA and the Department of Energy have been advancing a novel radioisotope power system (RPS) based on dynamic energy conversion. This approach will manifest a dynamic RPS (DRPS) option with a conversion efficiency at least three times greater than a thermoelectric-based RPS. Significant progress has recently been made toward this end. A one-year system design phase has been completed by NASA industry partner Aerojet Rocketdyne, which resulted in a DRPS with power of 300 watts-electric (We) with convertor-level redundancy. In-house technology development at the NASA Glenn Research Center (GRC) has demonstrated the conversion devices in relevant environments and has shown all requirements can be met. Progress has also been made on the control electronics necessary for dynamic energy conversion. Flight-like controllers were recently upgraded and achieved an 11-percentage-point increase in efficiency. Control architectures have been developed to handle the multiconvertor arrangements in the latest DRPS design. A system-level DRPS testbed is currently being assembled that will experimentally demonstrate the DRPS concept being pursued.
Members of the Consortium for Nuclear Forensics. (Image: University of Florida)
A 16-university team of 31 scientists and engineers, under the title Consortium for Nuclear Forensics and led by the University of Florida, has been selected by the Department of Energy’s National Nuclear Security Administration (NNSA) to develop the next generation of new technologies and insights in nuclear forensics.
Artist’s concept of the DRACO spacecraft, which will demonstrate a nuclear thermal rocket engine. (Image: DARPA)
NASA and the Defense Advanced Research Projects Agency (DARPA) have announced they will collaborate on plans to launch and test DARPA’s Demonstration Rocket for Agile Cislunar Operations (DRACO). DARPA has already worked with private companies on the baseline design for a fission reactor and rocket engine—and the spacecraft that will serve as an in-orbit test stand—and has solicited proposals for the next phase of work. Now NASA is climbing on board, deepening its existing ties to DRACO’s work in nuclear thermal propulsion (NTP) technology—an “enabling capability” required for NASA to meet its Moon to Mars Objectives and send crewed missions to Mars. NASA and DARPA representatives announced the development at the American Institute of Aeronautics and Astronautics SciTech Forum in National Harbor, Md., on January 24.
A rendering of Helga and Zohar side by side aboard the Orion spacecraft. (Image: NASA/Lockheed Martin/DLR)
NASA’s Artemis I mission, successfully launched at 1:47 a.m. EST on November 16 from the Kennedy Space Center in Florida, will travel 40,000 miles beyond the moon—farther from Earth than any human-crewed space mission has flown before. The historic trip was launched by the world’s largest rocket, the Space Launch System (SLS), nearly 50 years after NASA last sent humans to the moon. And while no humans are on board the Orion spacecraft, two fabricated crew members—“Luna Twins” Helga and Zohar—were assembled with thousands of sensors to obtain the best estimates yet of cosmic radiation exposure to human tissues during space travel.
A Northrop Grumman Antares rocket, with the Cygnus spacecraft Sally Ride aboard (so named for first American woman to fly in space), launched at 5:32 a.m. EST on November 7, from NASA's Wallops Flight Facility in Virginia. The rocket is captured just after liftoff in this still image from NASA’s live broadcast of the event.
Seeds from the joint laboratories of the International Atomic Energy Agency and the Food and Agriculture Organization of the United Nations (FAO) are onboard a Cygnus spacecraft launched from NASA’s Wallops Flight Facility in Virginia early on November 7. Now orbiting the Earth en route to the International Space Station, the seeds are part of a commercial resupply mission with a payload that includes resources to support more than 250 scientific investigations.
A conceptual illustration of a fission surface power system. (Image: NASA)
Three teams have been picked to design a fission surface power system that NASA could deploy on the moon by the end of the decade, NASA and Idaho National Laboratory announced today. A fission surface power project sponsored by NASA in collaboration with the Department of Energy and INL is targeting the demonstration of a 40-kWe reactor built to operate for at least 10 years on the moon, enabling lunar exploration under NASA’s Artemis program. Twelve-month contracts valued at $5 million each are going to Lockheed Martin (partnered with BWX Technologies and Creare), Westinghouse (partnered with Aerojet Rocketdyne), and IX (a joint venture of Intuitive Machines and X-energy, partnered with Maxar and Boeing).
Artist’s rendering of USNC spacecraft using EmberCore. (Image: DIU)
The Defense Innovation Unit (DIU), a Department of Defense organization focused on swiftly putting commercial technology to use in the U.S. military, has awarded contracts for two nuclear technologies—compact fusion and radioisotope heat—for spacecraft that could carry a high-power payload and freely maneuver in cislunar space. The objective is to accelerate ground and flight testing and launch a successful orbital prototype demonstration of each approach in 2027.
NETS participants are credited with helping relaunch the nation’s domestic production of Pu-238 to fuel the Mars Perseverance rover. (Photo: NASA)
Connecting nuclear engineers and scientists with space exploration missions has been a focus of the American Nuclear Society’s Aerospace Nuclear Science and Technology Division since its creation in 2008. One of the main ways those connections are made is through the Nuclear and Emerging Technologies for Space (NETS) conference, which the division supports in conjunction with the National Aeronautics and Space Administration.
Ben Campbell, a graduate research assistant and master’s degree student in aerospace systems engineering, works on the Bubbling Liquid Experiment Navigating Driven Extreme Rotation, or BLENDER, device at UAH’s Johnson Research Center. (Photo: UAH/Michael Mercier)
With three commercial teams under contract to produce reactor designs for nuclear thermal propulsion rockets that would use solid high-assay low-enriched uranium fuel to heat hydrogen propellant, NASA’s investment in nuclear thermal propulsion (NTP) has increased in recent years. But just as there is more than one way to fuel a terrestrial reactor, other fuels are under consideration for future NTP rocket engines.
Coated uranium fuel kernels, as viewed through a glovebox. (Photo: BWXT)
Nuclear thermal propulsion (NTP) is one technology that could propel a spacecraft to Mars and back, using thermal energy from a reactor to heat an onboard hydrogen propellant. While NTP is not a new concept, fuels and reactor concepts that can withstand the extremely high temperatures and corrosive conditions experienced in the engine during spaceflight are being designed now.
BWX Technologies announced on December 13 that it has delivered coated reactor fuels to NASA for testing in support of the Space Technology Mission Directorate’s NTP project. BWXT is developing two fuel forms that could support a reactor ground demonstration by the late 2020s, as well as a third, more advanced and energy-dense fuel for potential future evaluation. BWXT has produced a videoof workers processing fuel kernels in a glovebox.
Diablo Canyon nuclear plant. (Photo: PG&E)
Last April, Entergy had to close its Indian Point nuclear plant. That’s despite the plant’s being recognized as one of the best-run U.S. nuclear plants. That’s also despite its 20-year license extension process having been nearly completed, with full support from the Nuclear Regulatory Commission.
This closure was due in large part to opposition by antinuclear environmental groups. These groups also mobilized existing negative public opinion on nuclear energy to get politicians to oppose the plant’s license extension. Another factor is unfair market conditions. Nuclear energy doesn’t get due government support—unlike solar, wind, and hydro—despite delivering clean, zero-emissions energy.