Nuclear thermal propulsion ship
An illustration of a spacecraft for deep space missions powered by nuclear thermal propulsion. Congress has added funding to NASA appropriations bills to support development of the technology. Credit: NASA/Marshall

As the audience settled into their seats at the National Air and Space Museum’s Udvar-Hazy Center for the latest meeting of the National Space Council Aug. 20, they were treated to a soundtrack of classic rock and pop music. Well, “treated” might be too strong of a word: as the start of the meeting was delayed, attendees discovered that the playlist was both rather limited — some songs played two or three times — and were simply staples of Trump campaign rallies, rather than having anything to do with space.

One song, though, stood out: The Rolling Stones’ “Time Is on My Side.” It seemed to be just the opposite of the urgency impressed on NASA at the previous council meeting in March, when Vice President Mike Pence called on the agency to land humans on the moon by 2024. The agency has been dashing ever since to speed up its plans.

Time, though, does seem to be back on the side of one space exploration technology: nuclear power. At the meeting, the council endorsed a new policy for approving the launch of space nuclear power systems, and also heard testimony about the importance of nuclear power. Congress, meanwhile, has been adding money to NASA’s budget earmarked for development of nuclear thermal propulsion systems, while NASA works on Kilopower, a compact nuclear reactor that could power bases on the moon or Mars.

The argument that supporters of space nuclear power make is that the technology is essential for NASA’s long-term exploration efforts, providing power where solar panels won’t work, like the two-week lunar night, or propulsion that can dramatically shorten travel times for missions to Mars. Advocates have tried to make that case for decades, but only now seem to be gaining traction.

“If we are to fulfill the objectives of President Trump’s first space policy directive to establish a long-term presence on the moon and send the first crewed mission to Mars, nuclear power is arguably the most important technology to enable these bold national goals,” said Rex Geveden, a former NASA associate administrator and current chief executive of BWX Technologies, a company that specializes in nuclear power, in his testimony at the council meeting.

The problem for nuclear power is that their long-term value may clash with the short-term expediency of NASA’s sprint to the moon. Nuclear thermal propulsion could potentially cut the travel time for Mars missions by months, but isn’t needed for three-day trips to the moon. Kilopower can keep a lunar base running during the two-week night, but isn’t needed for the initial short-stay lunar landings.

When the next budget crunch hits — which seems inevitable as the growing budget demands for Artemis eclipse the willingness of Congress to increase overall NASA spending — programs not needed to achieve the 2024 goal could be in jeopardy, including space nuclear power.

NASA Administrator Jim Bridenstine, perhaps sensing this, tried to emphasize other applications for space nuclear power at the council meeting. After Geveden noted that space nuclear power could have terrestrial military applications, like powering a directed energy weapon, Bridenstine asked, “Could that directed energy weapon be used, for example, to protect Earth from an asteroid?”

“I think you could envision that,” Geveden responded.

“Could it be used to take debris out of orbit?” Bridenstine asked. Geveden agreed.

“There’s an amazing opportunity here that the United States of America should take advantage of,” Bridenstine concluded.

Not discussed was the cost of such applications or their challenges, particularly policy ones. If some members of the public remain concerned about launching even relatively innocuous RTGs to power robotic missions to the outer solar system, imagine how they’ll feel about a space-based nuclear-powered laser shooting at objects in orbit.

For now, at least, space nuclear power advocates can finally get some satisfaction that their technologies are getting attention and funding. The problem, as the Stones told us decades ago, is that you can’t always get what you want.


“Foust Forward” appears in every issue of SpaceNews magazine. This column ran in the Sept. 2, 2019 issue. Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews.