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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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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Dragonfly, a Pu-fueled drone heading to Titan, gets key NASA approval
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
Stanley E. Turner, Thomas G. Haynes III
Nuclear Technology | Volume 169 | Number 2 | February 2010 | Pages 195-203
Technical Note | Radiation Protection | doi.org/10.13182/NT10-A9362
Articles are hosted by Taylor and Francis Online.
Neutron attenuation measurements have been used as an instrumental method of analyzing (normally flat) test coupons for the concentration of the 10B nuclide. Calibrated standards of well-characterized 10B content are used to interpret the observed neutron counting rates into the 10B areal density. Recently, there have been challenges to the validity of neutron attenuation measurements and their relationship to criticality safety analyses. For the most part, these challenges have been verbal without any supporting data. The present study was undertaken to provide experimental and analytical investigations of these challenges. The challenges are as follows: 1. It has been claimed that neutrons of any energy (including epithermal and fast neutrons) can be used for attenuation measurements. Spectral and reaction rate calculations are presented to demonstrate that only thermal neutrons have sufficient sensitivity to yield reliable neutron attenuation measurements because of the fundamental 1/v absorption cross section of 10B. 2. It has been alleged that only small-diameter [0.953 cm (3/8 in.)] neutron beams are acceptable for neutron attenuation measurements and that larger-diameter [2.54 cm (1 in.)] beams would "mask" any defects or significant nonuniformities. Both experimental and analytical data are presented to show that the measurements are independent of beam size and that adequate sensitivity to detect any defects or nonuniformities is provided. Criticality calculations are also presented to illustrate that small defects (holes or cracks) have very small effects on results of criticality analyses. 3. It has been postulated that in absorbers using particles of boron carbide, neutrons could stream past discreet particles, reducing the effectiveness of the absorber. While this may be true in attenuation measurements, there is no evidence that neutron streaming has any significant effect in criticality safety analyses. Calculations and an explanation are presented. Neutron attenuation and criticality analyses refer to physically different phenomena with appreciably different path lengths rendering criticality analyses insensitive to streaming.
