NASA's Nuclear-Powered SR-1 Spacecraft Targets Mars by 2028
NASA advances SR-1 nuclear reactor spacecraft for Mars flight by 2028 building on prior NTP and fission power programs.
NASA administrator Jared Isaacman announced the SR-1 Freedom nuclear reactor-powered interplanetary spacecraft for a Mars mission by the end of 2028 (MIT Technology Review, 2026).
Nuclear fission provides higher energy density than chemical propellants enabling longer duration and faster interplanetary transit according to Simon Middleburgh Bangor University and Lindsey Holmes Analytical Mechanics Associates (MIT Technology Review). RTGs powered Voyager and Cassini via plutonium decay heat but SR-1 advances to a true reactor for both electricity and propulsion independent of solar arrays (MIT Technology Review).
The 2028 timeline follows prior conceptual studies and connects to NASA's DRACO nuclear thermal propulsion demonstration initiated in 2021 plus Kilopower fission surface power tests completed in 2018 (NASA.gov 2023). Coverage provided few technical specifications on reactor type or cooling method and omitted explicit linkage to concurrent lunar surface reactor plans referenced in the same briefing.
AXIOM: SR-1 links terrestrial small modular reactor designs with space fission systems potentially cutting Mars transit from six months to under three months and supporting sustained exploration beyond chemical limits.
Sources (3)
- [1]NASA is building the first nuclear reactor-powered interplanetary spacecraft. How will it work?(https://www.technologyreview.com/2026/04/14/1135848/nasa-nuclear-powered-spacecraft/)
- [2]DRACO Nuclear Propulsion(https://www.nasa.gov/directorates/stmd/nuclear-propulsion/draco/)
- [3]Kilopower Project(https://www.nasa.gov/directorates/spacetech/kilopower/)