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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 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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A webinar, and a new opportunity to take ANS’s CNP Exam
Applications are now open for the fall 2025 testing period for the American Nuclear Society’s Certified Nuclear Professional (CNP) exam. Applications are being accepted through October 14, and only three testing sessions are offered per year, so it is important to apply soon. The test will be administered from November 12 through December 16. To check eligibility and schedule your exam, click here.
In addition, taking place tomorrow (September 19) from 12:00 noon to 1:00 p.m. (CDT), ANS will host a new webinar, “How to Become a Certified Nuclear Professional.” More information is available below in this article.
Yale Chang
Nuclear Technology | Volume 207 | Number 6 | June 2021 | Pages 844-850
Technical Note | doi.org/10.1080/00295450.2020.1855946
Articles are hosted by Taylor and Francis Online.
National Security Presidential Memorandum-20 (NSPM-20) (Launch of Spacecraft Containing Space Nuclear Systems) provides updated guidelines for launch authorization for three categories of proposed launches of spacecraft with space nuclear systems: Federal government civil space including the National Aeronautics and Space Administration (NASA), Federal government defense and intelligence, and commercial. These space nuclear systems provide power, heat, and/or propulsion to the spacecraft. NSPM-20 requires a rigorous, risk-informed safety analysis and launch authorization process. The launch approval process of previous NASA missions each took several years and cost multimillion dollars. NSPM-20 provides guidelines to potentially streamline the process and improve cost and schedule. This technical note examines three NSPM-20 guidelines on a future example interplanetary mission (EIM) as to their potential implementation feasibility for three accident categories: Earth gravity assist reentry, solid propellant fires, and flight termination system design. It is found that the safety technology for these accidents were constantly improved over the last several missions, but in some cases may not be adequate for direct use in the EIM’s launch authorization process.