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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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255 records · Page 15

The Future of Astronaut Nutrition: Daily Production of Kefir Nutrient Packs in a Lunar Analog Mission

Astronaut nutrition will need to be supplemented with fresh nutrients and probiotics for long duration space travel. Kefir is a fermented milk beverage that provides probiotic bacteria, protein, calcium, and vitamin K. It has been historically cultured for thousands of years and is a modern-day health food. During the BioNutrients-2 experiment, one generation of kefir was cultured by astronauts on the ISS in fluorinated ethylene propylene (FEP) bags. This follow-on experiment aimed to test the hypothesis that kefir can be produced at ambient temperatures and safely passaged to make a series of nutrient packs in an analog environment. The Hawaiian Space Exploration Analog and Simulation (HI-SEAS) is a semi-controlled habitat located on the Mauna Loa volcano on the island of Hawaii at 2,500 m elevation. The recent EMMIHS (EuroMoonMars, International MoonBase Alliance, HI-SEAS) missions comprised of interdisciplinary, international crews for mock lunar missions. During a six-day mission in March 2024, crew members tested continuous passaging of kefir cultures (C-FIR commercial strain). After approximately 24 hours of growth, a portion of culture was used to seed the next generation of culture bags for four passages. A color board and pH indicator allowed the crew to easily determine when the culture had reached optimal pH. Laboratory analysis at NASA Ames Research Center showed that the pH met Kefir standards (<5). The yeast and lactic acid bacteria were in normal range and no contamination was detected in the final passage. By successfully accomplishing this experiment the team has demonstrated the ability to safely produce daily cultures of kefir in a microgravity applicable growth system.

Astronaut nutrition↗

Dusty Environment Classification and Testing: Dust Mitigation Slide Wipes & Tapes

During the Apollo missions many mechanisms, equipment, and surfaces were contaminated by lunar dust and often negatively affected. The methods used to clear these devices of dust proved ineffective, which led to premature failure in some cases. Systems being designed for upcoming missions to the Moon will need to address the performance degradation risk of dust contamination. Surfaces at risk include thermal control surfaces, solar cells, camera and sensor optics, seals, metal joints and tools, and space suit assemblies. To improve state of the art dust mitigation approaches, the dust mitigation team at NASA Glenn Research Center (GRC) explored the effects imposed on substrates during cleaning activities in the presence of lunar dust. The Uniform Dust Deposition System (UDDS) was used to conduct a study of various cleaning techniques on different substrates. Test substrates and cleaning media were selected to represent a wide range of structural and functional materials. Substrates included orthofabric, thermal radiator coating, aluminum, quartz glass, silicone rubber, aluminized Mylar, and FEP. Cleaning materials included cloth wipes, tapes, a brush, and a pliable cleaner concept. Cleaning material / substrate pairs were rated on cleaning efficiency, substrate damage, cleaning material longevity, and ease of use. The best performing cleaning method varied based on application.

lunar simulant↗

Radiation Dose Testing on Juno High Voltage Cables

The Juno mission to Jupiter will have a highly elliptical orbit taking the spacecraft through the radiation belts surrounding the planet. During these passes through the radiation belts, the spacecraft will be subject to high doses of radiation from energetic electrons and protons with energies ranging from 10 keV to 1 GeV. While shielding within the spacecraft main body will reduce the total absorbed dose to much of the spacecraft electronics, instruments and cables on the outside of the spacecraft will receive much higher levels of absorbed dose. In order to estimate the amount of degradation to two such cables, testing has been performed on two coaxial cables intended to provide high voltages to three of the instruments on Juno. Both cables were placed in a vacuum of 5x10(exp -6) torr and cooled to -50(deg)C prior to exposure to the radiation sources. Measurements of the coaxial capacitance per unit length and partial discharge noise floor indicate that increasing levels of radiation make measurable but acceptably small changes to the F EP Teflon utilized in the construction of these cables. In addition to the radiation dose testing, observations were made on the internal electrostatic charging characteristics of these cables and multiple discharges were recorded.

partial discharge↗