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OSTP memo guides space nuclear plan
A White House Office of Science and Technology Policy (OSTP) memorandum released on Tuesday guides NASA, the Department of Energy, and the Department of Defense on their roles in deploying near-term space nuclear power.
This follows a series of NASA announcements last month—driven by the executive order “Ensuring American Space Superiority,” issued by Trump in December—including an ambitious timeline for establishing a moon base, which would rely on fission surface power (FSP) to survive the long lunar night at the moon’s south pole, and plans for a nuclear electric propulsion (NEP) rocket to be launched in 2028.
M. M. R. Williams
Nuclear Science and Engineering | Volume 199 | Number 7 | July 2025 | Pages 1107-1161
Research Article | doi.org/10.1080/00295639.2024.2444147
Articles are hosted by Taylor and Francis Online.
An extension of the work of Pázsit, Dykin, and Darby on multiplet evaluation has been made using a different method of solution and with the addition of an external reflecting material. The method of solution uses the scalar form of the transport equation to calculate the singlet, doublet, and triplet moments, and in the case when the source configuration requires it, the angular distribution can be obtained in terms of the scalar quantities by direct quadrature. The main contribution of this work is to demonstrate that the scalar approach is convenient, and if energy and anisotropic scattering are required, it is reasonably easy to make use of existing computer codes for solutions of the neutron transport equation. Also, it is shown that the addition of an external reflecting region can have a significant effect on the three multiplicity moments. Some numerical results are given to enable direct comparison to be made with other methods of solution.