An artist’s conception shows a space probe firing its nuclear thermal propulsion system. (DARPA illustration)
The idea of launching atomic bombs may sound like a national security nightmare, but the right kind of atomic bombs is likely a must for long-term space exploration.
At least one panel of experts at the interface between the space and nuclear industries described the state of affairs this week at the annual virtual meeting of the American Nuclear Society.
“To do significant activities in space, you need energy. And to get that energy … it’s complicated, “said Paolo Venneri, CEO of a Seattle-based nuclear power company called USNC-Tech.
Even if you build a hydrogen fuel plant on the moon or on Mars, the electricity to run those plants has to come from somewhere. And studies suggest that solar power alone won’t be enough.
“The sun is great, but only within a certain region of the solar system,” said Venneri. “And if you want to have high-performance applications over the long term, you need a nuclear power plant.”
George Sowers, a veteran of the aerospace industry who is now an engineering professor at the Colorado School of Mines, calculated the energy required for a lunar operation that would mine polar ice to produce fuel, drinking water and air for future astronauts. He reckons with a 2 megawatt nuclear power plant to convert the H2O into hydrogen and oxygen.
Nuclear power is also being studied for propulsion in space: Amazon founder Jeff Bezos’ Blue Origin is one of the companies working on a Pentagon project that aims to demonstrate a nuclear thermal propulsion system beyond low earth orbit in 2025 to propel heat Rocket fuels, while nuclear electric propulsion systems generate power for ion thrusters.)
The project is funded by the Defense Advanced Research Projects Agency (DARPA) and is known as the Demonstration Rocket for Agile Cislunar Operations (DRACO). Blue Origin’s commercial partners at DRACO are General Atomics who will develop the nuclear reactor; and Lockheed Martin, who will be working on the spacecraft concept with Blue Origin.
During DRACO’s first 18-month design phase, General Atomics is slated to receive $ 22.2 million, while Blue Origin and Lockheed Martin will receive $ 2.5 million and $ 2.9 million, respectively. DARPA will issue separate calls for future phases.
DARPA is interested in nuclear thermal propulsion because they promise to be up to five times more efficient than traditional chemical propulsion, with a thrust-to-weight ratio 10,000 times greater than electric propulsion systems.
Venneri said USNC-Tech is supporting Blue Origin and General Atomics at DRACO. “We’re working with Blue Origin on a few other things as well, but that’s still open [to be determined] in terms of information, ”he added.
USNC-Tech is also working with Aerojet Rocketdyne, which has facilities in Redmond, Wash., On research into nuclear thermal propulsion. Venneri said his company is involved in another collaboration with Seattle-based First Mode to develop a new type of rechargeable atomic battery for space missions. Just in the past few months, USNC-Tech has received a total of $ 250,000 in grants from NASA for studies focusing on nuclear batteries and an ultra-high temperature facility to test materials that could be used in space for nuclear reactors.
In a sense, nuclear power has been around in space for decades: Plutonium-powered thermoelectric radioisotope generators or RTGs have supplied power to NASA missions, from the Apollo moon landing to the Voyager space probe to the rovers Curiosity and Perseverance Mars.
Placing a full-fledged nuclear reactor on a spaceship or on the surface of the moon or Mars would make things even better. Back in 2004, NASA came up with a plan to put a small reactor on a probe that would have examined Jupiter and its moons – but the mission was canceled the following year due to technical challenges and budget constraints.
NASA and the Department of Energy’s National Nuclear Security Administration successfully completed ground testing of a next-generation nuclear reactor nicknamed KRUSTY for NASA’s Kilopower Space Reactor program in 2018.
The goal of the program is to bring a 10-kilowatt demonstration reactor to the surface of the moon by 2027. But Dave Poston, who designed the Kilopower reactor at Los Alamos National Laboratory and named the Chief Technology Officer for a spin-off from Los Alamos. is Space Nuclear Power Corp. – said progress was slow.
“Nothing really happened in the last three years,” he said. NASA is still working on a tender for a moon-based nuclear power plant.
Safety is a big issue with atomic bombs in space: According to the current regulatory system, every start of a plutonium-powered generator must be approved by the president. Next generation nuclear batteries that use uranium instead of plutonium may not have such severe restrictions. Nonetheless, all projects that require the deployment of nuclear materials into space are being scrutinized.
Even within the nuclear industry there is a debate about the use of high enriched uranium (HEU) versus low enriched uranium (LEU) in space. Safety concerns are one of the reasons NASA’s nuclear plans have stalled.
“I’m not going to be discussing HEU vs. LEU here,” said Ron Faibish, Senior Director of Business Development at General Atomics’ Nuclear Technologies and Materials Division. “I think every system has its advantages. I’m just saying it’s a design problem and you can design for safety. “
A space directive enacted in the final days of the Trump administration could help make nuclear power an accepted part of the American space effort. But Rick Tumlinson, a longtime advocate of space commercialization and a founding partner of a space-focused venture capital firm called SpaceFund, said there was no room for missteps.
“It’s a very tangled area because it’s new and so it needs to be worked out very carefully,” said Tumlinson. “The other challenge is that there are some countries that are very interested in space and not have to worry about public opinion when it comes to launching nuclear weapons. And I could see how they got a jump while we all wrestle over who’s fixing it and who’s doing it. “
Will nuclear power become a factor in America’s growing space rivalry with China? That really sounds like a national security nightmare.
Contributing Editor Alan Boyle hosted the “Per Nuclear Ad Astra” panel discussion during this week’s annual meeting of the American Nuclear Society.