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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Japan gets new U for enrichment as global power and fuel plans grow
President Trump is in Japan today, with a visit with new Prime Minister Sanae Takaichi on the agenda. Takaichi, who took office just last week as Japan’s first female prime minister, has already spoken in favor of nuclear energy and of accelerating the restart of Japan’s long-shuttered power reactors, as Reuters and others have reported. Much of the uranium to power those reactors will be enriched at Japan’s lone enrichment facility—part of Japan Nuclear Fuel Ltd.’s Rokkasho fuel complex—which accepted its first delivery of fresh uranium hexafluoride (UF₆) in 11 years earlier this month.
Christopher G. Morrison
Nuclear Technology | Volume 206 | Number 8 | August 2020 | Pages 1224-1239
Technical Paper | doi.org/10.1080/00295450.2020.1738173
Articles are hosted by Taylor and Francis Online.
The specific mass (or mass per unit power) is a fundamental performance metric in space power systems. For surface power, a low specific mass reduces launch costs and lander size. For nuclear electric propulsion, a low specific mass enables fast transit within the solar system. Studies on specific mass have typically focused on point designs and have not adequately explored the design space and scaling of specific mass. This research explores the design space for radiatively cooled closed nuclear Brayton systems. Specifically, the key innovation in this work is to determine the scaling according to the maximum temperature capability and total power system power. When these two factors are analyzed together, the resulting analyses show a clear scaling for specific mass.