NASA Is Working To Solve Critical Space Material Shortage

For scientific survey probes and landers that head into deep space, power generation is a critical problem: think of exploring space like backpacking across a continent a place like Antarctica: no stores, no roads, and months and months of cold temperatures. Solar power is handy, light and handy, but useless at night or in a blizzard. NASA’s nuclear technology could offer a solution in such scenarios.

The problem is that the US does not have enough of the material needed to power the most common classes of RPSs, plutonium-238 (Pu-238). Plutonium exists naturally, but only in tiny trace amounts, primarily produced by neutron capture in uranium in the Earth’s crust. Mining it is out, because finding usable quantities in nature would be prohibitively expensive and undoubtedly environmentally devastating. That means that we must create it artificially, usually in purpose-built nuclear reactors.

What Happened?

The U.S. stopped producing plutonium-238 in 1988 primarily because of the winding down of the Cold War. The single facility that could make it, the the Savannah River Site in South Carolina, was shut down. At that time, the nation had a surplus of the isotope, which was a byproduct of the weapons-grade plutonium production, and the need for it for nuclear weapons was reduced. The aging reactors used for this production were shut down, halting both weapons-grade plutonium and Pu-238 output.

Restarting Production

The United States restarted production in 2015 and is steadily scaling up plutonium-238 production at government facilities in Oak Ridge, Tennessee; Idaho; and Los Alamos, New Mexico. NASA nuclear initiatives now rely significantly on these domestic sources. The Department of Energy (DOE) says it remains on track toward its average 1.5 kg/year Pu-238 target for civil space use, with large production shipments resuming and process improvements continuing at the High Flux Isotope Reactor (HFIR) and Idaho’s Advanced Test Reactor (ATR). Recent technical papers and lab updates detail higher neptunium loadings, qualified ATR positions, and shipping/logistics upgrades that increase efficiency and output.

At Oak Ridge, “production-quantity” batches underscore the maturing U.S. supply chain after decades without domestic manufacture. Material from the restart already contributed to NASA’s Perseverance rover, and ORNL reports continued gains in manufacturing automation and target performance that underpin routine output. Idaho’s program notes multiple ATR positions qualified for Pu-238 target stacks and active work to raise neptunium oxide loadings from ~20% toward ~30%—a lever to boost annual yield without new reactors.

Help From Foreign Sources

Friendly international production of Pu-238 itself is currently at the feasibility stage. The Canadian Space Agency commissioned a 2024 study to evaluate irradiating neptunium-237 in Canadian power reactors (leveraging Canada’s deep isotope production infrastructure) and to map costs through separation and delivery. This cooperation could also aid NASA’s nuclear exploration goals.

While not yet a production line, the work signals a credible allied route to reinforce and diversify the Pu-238 supply chain. Time will tell.

What’s next

DOE’s Pu-238 plan focuses on process intensification (higher target loading, more qualified reactor positions, faster logistics) to hold a ~1.5 kg/year cadence for NASA missions. The incorporation of NASA’s nuclear plans plays a crucial role here.

In parallel, Europe and the UK are pressing Am-241 toward space-ready units, and U.S. industry is standing up an Am-241 commercial supply chain—moves that could relieve demand pressure on Pu-238 and broaden mission options for long-life surface and deep-space systems. Industry consensus is that the first integrated Am-241 system demos are moving from test stands to mission manifests somewhere in the 2028 time frame.