NASA SR-1 Freedom Power System Award Brings Kratos $33.6 Million

Kratos Defense & Security Solutions (KTOS ) on October 28, 2026 announced a $33.6 million contract award to design, build, and deliver the power conversion system for NASA’s Space Reactor-1 Freedom spacecraft, which is targeted for launch in 2028.

NASA announced the SR-1 Freedom mission during its “Ignition” event and describes the vehicle as humanity’s first fission-powered spacecraft to travel beyond Earth’s orbit. The mission will demonstrate nuclear electric propulsion in deep space and deliver the agency’s SkyFall science payload to Mars.

Kratos will execute the work as a subcontractor to Sierra Lobo, Inc., under Sierra Lobo’s NASA SpaceDOC III contract. NASA’s Glenn Research Center stated in an October 20, 2026 article that Sierra Lobo Inc. will provide the nuclear power module’s closed Brayton cycle power conversion system under the Space Flight Systems Development and Operations Contract III, awarded in 2024 to support spaceflight hardware design, development, testing, and operations at Glenn in Cleveland.

Under the subcontract, Kratos will provide a compact, space-qualified closed Brayton cycle power conversion system. The company described the unit as the mechanical bridge between SR-1 Freedom’s onboard fission reactor and the spacecraft’s power distribution and electric propulsion subsystems, converting the thermal energy generated by the reactor into the electrical power required to drive the propulsion thrusters and sustain spacecraft operations.

According to the company, nuclear electric propulsion uses a fission-based nuclear power module to generate electricity for electric thrusters rather than relying solely on conventional chemical propulsion. By accelerating charged particles to create continuous thrust, NEP-equipped spacecraft can operate for months or years and reach Mars using significantly less propellant than chemically propelled spacecraft, freeing mass for scientific instruments, cargo, and future crew-support equipment.

“Being selected to power SR-1 Freedom is a generational honor for Kratos,” said Stacey Rock, President of the Kratos Turbine Technologies Division.

Reactor Integration and Safety Process

NASA stated that SR-1 Freedom’s nuclear power module, located at the end of the spacecraft’s boom, consists of a reactor that generates heat through nuclear fission and the power conversion system that converts that heat into electricity for spacecraft systems and electric propulsion. The fission reactor is being designed and developed by the Department of Energy’s Idaho National Laboratory and will be integrated with the power conversion system to complete the module.

NASA said it and the Department of Energy apply safety standards throughout the spacecraft’s design and development, including interagency safety reviews, continuous oversight by a NASA chief safety officer, regulatory compliance, and a safety design process focused on hazards, failure tolerance, and nuclear safety. The reactor portion of SR-1 Freedom will remain inactive until the spacecraft leaves Earth orbit, according to the agency.

To expedite development of the spacecraft, NASA and its partners mutually agreed to key contract actions advancing the mission, the agency said. “These contract actions not only reduce technical risk and help us maintain momentum toward our 2028 launch, but they also strengthen collaboration across our partners,” said Steve Sinacore, SR-1 Freedom program director.

Vehicle Specifications and the SkyFall Payload

NASA’s SR-1 Freedom mission page lists the spacecraft’s weight at about 26,455 pounds (12,000 kilograms), with High-Assay Low-Enriched Uranium (HALEU) fuel. The power system is a 20-kilowatt-electric closed Brayton cycle power conversion system, the Power and Propulsion Element spacecraft bus generates 48 kilowatts of electrical power, and propulsion comes from an Advanced Electric Propulsion System 12-kilowatt Hall thruster. Communications use X-band through NASA’s Deep Space Network.

The mission is a Martian flyby and science payload deployment conducted in partnership with the Department of Energy, with launch and target arrival listed as 2028 and 2029. NASA’s six stated mission objectives are operating a nuclear-electric propulsion system in space, launching on an Earth escape trajectory, utilizing the 2028 Mars launch window, leveraging existing technology and flight hardware to the maximum extent possible, delivering SkyFall to Mars intercept, and reactor extended performance.

SkyFall will use a mid-air deployment to deliver three Mars helicopters evolved from NASA’s Ingenuity Mars Helicopter design. According to NASA, the helicopters will carry an instrument package featuring ground-penetrating radar and imagers and will measure air temperature, wind speed, and direction to collect scientific data, demonstrate exploration zones, and identify potential water ice sources. NASA noted that Mars’ atmosphere has only 1% of the air pressure at Earth’s surface and that the helicopters fly with two 4-foot-wide (1.4 meter) rotor blades; the agency is planning a landing site selection process targeting flat, low-elevation areas free of many geological obstacles.

Kratos said the mission aims to launch the first U.S. space reactor since 1965. NASA describes SR-1 Freedom as the first step in a deliberate sequence that will inform and enable Lunar Reactor-1, a fission surface power system intended to keep NASA’s Moon Base operating through periods of darkness and in locations where solar power alone is insufficient.

Kratos said the award adds to its expanding portfolio of advanced propulsion, power, and hypersonics work and reinforces its corporate strategy of leveraging internal investments to support national security and next-generation space programs.