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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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Nuclear Science and Engineering
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Fusion Science and Technology
Latest News
High temperature fission chambers engineered for AMR/SMR safety and performance
As the global energy landscape shifts towards safer, smaller, and more flexible nuclear power, Small Modular Reactors (SMRs) and Gen. IV* technologies are at the forefront of innovation. These advanced designs pose new challenges in size, efficiency, and operating environment that traditional instrumentation and control solutions aren’t always designed to handle.
Technical Session|Fission Surface Power
Tuesday, May 6, 2025|10:00–11:40AM CDT|Atlantis/Discovery/Columbia (Marriott)
Session Chair:
Gregory Fedor (NASA Glenn Research Center)
Session Organizer:
Alternate Chair:
Mark Lefebvre (NASA Glenn Research Center)
Track Organizer:
Harold Gerrish (Marshall Space Flight Center)
Space fission power systems are new and upcoming. They present both technological and legal/regulatory challenges. This technical session will offer insight into system concepts/trades for Fission Surface Power components and applications along with a consideration of the liabilities of such applications. Presenter bios: Dr. Clarence H. Tolliver III is a USPTO Registered Patent Attorney and an Associate in the Energy practice group at Pillsbury Winthrop Shaw Pittman, LLP. His practice involves licensing, export control, international business, and regulatory matters in service to clients across the fission, fusion, renewables, hydrogen, aviation and aerospace, and space and satellite industries Lee Mason is NASA’s Senior Technologist for Aerospace Power Systems stationed at Glenn Research Center in Cleveland Ohio. His primary area of expertise is space nuclear power & propulsion systems and has made major contributions to projects that included SP-100, DIPS, Prometheus, JIMO, ASRG, FSP 1.0, and Kilopower Sung Nam Lee is a researcher of KAERI from 2011. He was on secondment in IAEA as consultant in 2012 and was research resident in ANL in 2023. He is the Korea representative of VHTR CMVB from 2020. His research area is thermal hydraulic analysis in the gas cooled reactor and heat pipe cooled reactor and fission product transport in HTGR.
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U.S. Commercial Launches of Space Nuclear Systems - Insurance and Indemnification Considerations
10:00–10:25AM CDT
Clarence H. Tolliver (Pillsbury Winthrop Shaw Pittman), Sidney L. Fowler (Pillsbury Winthrop Shaw Pittman), Jeffrey S. Merrifield (Pillsbury Winthrop Shaw Pittman)
Attachment — Paper
Paper
Advanced Thermal Lunar Atomic System (ATLAS)
10:25–10:50AM CDT
Steve Sullivan (Univ. Rhode Island), Ryan Macaulay (Univ. Rhode Island), Jeffery Hahn (Univ. Rhode Island), Sami Akcakil (Univ. Rhode Island), Bahram Nassersharif (Univ. Rhode Island)
Key Design Trades for a Near-term Lunar Fission Surface Power System
10:50–11:15AM CDT
Lee Mason (NASA Glenn Research Center), Lindsay Kaldon (NASA Glenn Research Center), Sebastian Corbisiero (INL), DV Rao (INL)
Thermal Transport Analysis on Heat Pipe Reactor for Space
11:15–11:40AM CDT
Sung Nam Lee (KAERI), Sung Hoon Choi (KAERI), Hong-sik Lim (KAERI), Nam-il Tak (KAERI), Chan Soo Kim (KAERI)
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