NASA is preparing an interplanetary spacecraft powered by a nuclear fission reactor for launch to Mars in late 2028, President Donald Trump announced on Friday.
Speaking during a visit to the Johnson Space Center in Houston, Trump said the vehicle could become the first of a future American fleet designed to make deep space travel more frequent.
The project, officially designated as Space Reactor-1 Freedom or SR-1, aims to demonstrate nuclear fission propulsion beyond Earth orbit. The mission is scheduled to launch in 2028 and arrive in Martian space in 2029, where it will perform a flyby of the planet and release a scientific payload.
Nuclear propulsion and vehicle specifications
Freedom will utilize a nuclear-electric propulsion system, using an onboard space reactor to generate electricity that feeds its electric propulsion drives. Unlike conventional chemical rockets, nuclear-electric systems offer high fuel efficiency over long interplanetary distances.
The vehicle will weigh approximately 12,000 kilograms and will be fueled by high-assay low-enriched uranium, known as HALEU. Its power system features a 20-kilowatt closed Brayton cycle electrical energy conversion system paired with a 12-kilowatt Hall thruster.
Primary objectives for the mission include operating a nuclear-electric propulsion system in space, placing the vehicle on an Earth escape trajectory, and taking advantage of the 2028 Mars launch window.
Mars helicopters and scientific payload
The spacecraft will also transport the SkyFall mission to Mars, carrying three Martian helicopters built on the design of NASA's original Ingenuity aircraft. Ingenuity demonstrated powered flight on Mars after landing with the Perseverance rover in 2021.
The three aircraft are tasked with gathering scientific data, evaluating potential exploration zones, and identifying possible water sources across the Martian surface.
Freedom will not attempt a landing on Mars, but will deliver the SkyFall mission while conducting its planetary flyby.
Lunar power base and space academy
The Mars flight will also serve as a test for another NASA project, the Lunar Reactor-1 or LR-1. NASA intends to use the lunar reactor technology to supply power to its planned Lunar Base during extended periods of darkness and in shadowed regions where solar power alone is insufficient.
By evaluating the reactor in open space without the added complexity of a planetary landing, NASA aims to gain operational experience for future space nuclear missions.
During his Houston visit, Trump also signed an executive order to initiate the establishment of the United States Space Academy, modeled after existing American military service academies.
Trump stated that a nation cannot maintain a leading position on Earth while taking second place in space, adding that such an outcome simply would not work.
