NASA Tests Nuclear Rocket Engine Designed for Faster Deep-Space Missions

Nuclear rockets use reactor-heated propellant to achieve far higher efficiency than chemical engines. NASA reported in Jan 2026 that it completed cold-flow tests of a full-scale reactor development unit – the first such tests since the 1960s. At Marshall Space Flight Center, engineers ran over 100 tests on a 44×72-inch non-nuclear reactor model built by BWX Technologies. The project is led by NASA's Space Nuclear Propulsion Office as part of the DRACO nuclear rocket program.

Reactor Test Campaign

According to NASA, engineers conducted more than 100 cold-flow tests at the Marshall Space Flight Center using a full-scale 44x72-inch reactor model, which they tested in 2025. The BWX Technologies-built non-nuclear prototype demonstrates hydrogen flow in a nuclear thermal rocket engine. The tests established the design's control systems and fluid dynamics through testing. Engineers confirmed that the reactor continued to operate safely without dangerous oscillations or pressure waves. The test results led to improvements in the reactor's instrumentation and control systems, which would be used in future flight engines.

Implications for Spaceflight

Nuclear rockets provide advantages for deep-space exploration missions. They decrease the time needed for space travel, which enables astronauts to spend less time exposed to dangerous space radiation. The NASA representative, Greg Stover, explained that these technologies provide "speed and endurance", which enables faster travel and increased mission capabilities. Spacecraft can carry larger payloads because of their improved efficiency, which also enables them to operate essential equipment needed for extended space missions.

NASA Administrator Bill Nelson stated that this technology will allow astronauts to travel between deep space areas with unprecedented speed, which demonstrates nuclear propulsion's importance for NASA's Artemis program and Moon-to-Mars mission objectives. NASA and DOE are funding reactor development and advanced fuels to establish in-space demonstration capabilities through their joint research efforts.