NTP and its supporting technologies have great promise in spreading human presence to Mars and other locations beyond low earth orbit. USNC's accident tolerant reactor shutdown technology will address the water submersion criticality accident for NTP systems and help make NTP a viable technology to fulfill NASA human exploration needs. USNC's work directly aligns with the NASA Technological Roadmap 2015 TA 2: In-Space Propulsion Technologies: 2.2.3 Thermal Propulsion. Currently, NTP is being investigated for a human Mars Mission in the 2030s time frame, but a NTP system would be a game changing technology that would have application for a multitude of missions. In addition, USNC's accident tolerant reactor shutdown technology can be applied to small nuclear systems for space or surface power. These systems, like NTP systems, must also remain sub critical during a water submersion accident.The market for the NTP system and its supporting technologies extends beyond NASA with numerous potential customers in the private industry and defense sector. NTP is a game changing technology that is difficult to quantify in the non-NASA market but has the potential to be very large. USNC is currently pursuing earth based mobile reactors and small modular reactors. These reactors are different than traditional reactors as they can be shipped in whole or modular sections. In the shipment of these reactors it is essential to ensure that they are subcritical during water submersion (much like space reactors). The technology developed in this SBIR may have application in addressing water submersion in these earth-based reactors. In addition, a number of other companies are trying to bring mobile or small modular reactors to the market, creating a clear opportunity to implement the novel technology developed in this SBIR. The market potential for advanced reactors is several billions dollars and approximately 40 U.S. companies are trying to bring advanced nuclear technology to the market backed by a total of more than 1.3 billion dollars of private investment.