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2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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February 2026
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November 2025
Latest News
ORNL to partner with Type One, UTK on fusion facility
Yesterday, Oak Ridge National Laboratory announced that it is in the process of partnering with Type One Energy and the University of Tennessee–Knoxville. That partnership will have one primary goal: to establish a high-heat flux facility (HHF) at the Tennessee Valley Authority’s Bull Run Energy Complex in Clinton, Tenn.
Nuclear and Emerging Technologies for Space (NETS-2022) Plenary SPeaker
Tactical Technology Office (TTO)
Program Manager
DARPA
Maj. Nathan Greiner joined DARPA in July 2018 as a program manager in the Tactical Technology Office. His research interests include advanced power and propulsion technologies for land, sea, air, and space applications.
Before joining DARPA, Maj. Greiner completed a one-year fellowship at the Oak Ridge National Laboratory in Oak Ridge, Tennessee, where he focused on materials research. Previously, he served as a deputy branch chief and hypersonics research engineer in the U.S. Air Force Research Laboratory’s Aerospace Systems Directorate at Wright-Patterson Air Force Base, Ohio. He also has held positions as a liaison officer with U.S. Special Operations Command at Camp Lemonnier, Djibouti, and program manager for U.S. Special Operations Command at MacDill Air Force Base, Florida.
Maj. Greiner holds a Doctor of Philosophy in aeronautical engineering from the Air Force Institute of Technology, a Master of Science in mechanical engineering from the University of Utah, and a Bachelor of Science in mechanical engineering from the University of St. Thomas in St. Paul, Minnesota.
Last modified April 27, 2022, 4:36pm EDT