NASA and the U.S. military plan to launch a nuclear-powered spacecraft to Earth orbit in late 2025 or early 2026.
The project, generally known as DRACO (“Demonstration Rocket for Agile Cislunar Operations”), goals to present an in-space test to nuclear thermal propulsion (NTP), potentially revolutionary tech that might help humanity arrange shop on Mars and other distant worlds.
The DRACO spacecraft can be developed and built by Lockheed Martin, project team members announced today (July 26).
“We will put this together, we will fly this demonstration, gather a bunch of great data and really, we imagine, usher in a brand new age for the US [and] for humankind, to support our space exploration mission,” Kirk Shireman, vp of Lockheed Martin Lunar Exploration Campaigns, said during a press conference today.
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DRACO is not recent. The U.S. Defense Advanced Research Projects Agency (DARPA) began this system in 2021, and NASA got here aboard in early 2023.
NASA’s involvement should not be surprising; the agency’s interest in NTP tech goes way back. For instance, NASA aimed to launch a crewed Mars mission aboard a nuclear-powered spacecraft by 1979, via a program called NERVA (“Nuclear Engine for Rocket Vehicle Application”). This didn’t occur, after all; NERVA was canceled in 1972.
NASA remains to be shooting for the Red Planet, aiming to get astronauts there by the late 2030s or early 2040s. And it still views nuclear thermal propulsion as a key breakthrough that might make this goal more attainable, by slashing the travel time to and from the Red Planet.
Nuclear thermal rockets carry small fission reactors, which release incredible amounts of warmth as they split atoms. This heat is then applied to a propellant gas, which expands and is funneled into space through a nozzle to create thrust.
This process is distinct from the one employed by radioisotope thermoelectric generators (RTGs), nuclear tech that has been flying aboard probes for the reason that early days of the space age. RTGs don’t provide propulsion; they harness the warmth of radioactive decay to generate electricity, which then powers instruments, motors and other spacecraft gear.
In previous DRACO updates, DARPA and NASA have said they aim to launch this system’s first in-space demonstration by 2027. But that timetable could have moved up; Shireman said in today’s briefing that the goal launch window in the meanwhile is late 2025 or early 2026.
We got other details today as well. For instance, Lockheed is partnering with the Virginia-based company BWX Technologies, which can develop the DRACO spacecraft’s nuclear reactor and produce its HALEU (“high-assay low-enriched uranium”) fuel.
The spacecraft will head to a comparatively high orbit around Earth — likely somewhere between 435 and 1,240 miles (700 to 2,000 kilometers), team members said during today’s briefing. From such altitudes, it’ll take not less than 300 years for the DRACO demonstrator to fall back to Earth via atmospheric drag — long enough to be sure that all of its nuclear fuel is spent when it comes down.
The mission team will take pains to make sure safety on the best way up as well: The DRACO vehicle’s nuclear engine will only be activated once it reaches orbit. During launch, the engine can be equipped with a “poison wire,” a chunk of metal that absorbs neutrons, stopping them from initiating a series response. The poison wire acts much as control rods do in nuclear power reactors here on Earth, team members said.
DRACO is anticipated to operate in orbit for a couple of months. There are not any scientific instruments going up; “operation” entails the usage of its NTP engine, demonstrating that it could work for long stretches within the space environment.
Use of that engine, nevertheless, can even require keeping DRACO’s hydrogen — the spacecraft will launch with about 4,400 kilos (2,000 kilograms) of the stuff — super-cold, which is not any mean feat.
“Our life-limiting factor is how long we are able to keep the hydrogen cryogenic,” Tabitha Dodson, DRACO program manager at DARPA, said during today’s briefing. “That is just as much an illustration of on-orbit storage of cryogenic liquid hydrogen because it is a demo of the nuclear thermal rocket engine.”
Dotson added that, while the spacecraft’s specifications are still being worked out, it’ll principally consist of the NTP engine system and an enormous tank to carry the hydrogen. (She likened it to “a flying test stand.”) And the vehicle won’t require a heavy-lift rocket; it’ll be sufficiently small to suit contained in the fairing of a “standard” launcher like SpaceX’s Falcon 9.
We also got information in regards to the project’s cost. The contracts awarded to Lockheed and BWX Technologies for his or her DRACO work have a complete value of $499 million, provided all milestones are reached, Dotson said. Half of the cash will come from DARPA and half from NASA, she added.