International Journal of Microgravity Science and Application
Online ISSN : 2188-9783
Volume 37, Issue 3
Recent topics in levitation experiments, part 2
Displaying 1-4 of 4 articles from this issue
Recent topics in levitation experiments, part 2
  • Douglas M MATSON
    2020 Volume 37 Issue 3 Pages 370301-
    Published: July 31, 2020
    Released on J-STAGE: July 31, 2020
    JOURNAL OPEN ACCESS
    Management of a group of multi-institution research teams using a common facility, especially if any team involves an international partnership, requires development of procedures to minimize risk, encourage collaboration and promote communication. One effective management tool is the formation of an Investigator Working Group (IWG) where teams send representatives to meet with project stakeholders – including agency program managers, facility operations staff, and hardware developers – to work together to maximize scientific return from a space mission. Key tasks are tracking milestone progress, developing and resolving action items, responding to contingencies and opportunities for facility enhancement, negotiating use of critical limiting resources, presenting a united voice on what is best for science, developing a publication and data dissemination plan, and archiving lessons-learned.
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  • Hirohisa ODA, Chihiro KOYAMA, Masato OHSHIO, Hideki SARUWATARI, Takehi ...
    2020 Volume 37 Issue 3 Pages 370302-
    Published: 2020
    Released on J-STAGE: July 31, 2020
    JOURNAL OPEN ACCESS
    To take advantage of microgravity where huge electrical fields are not necessary to levitate samples using Coulomb force, zirconium samples were electrostatically positioned under an argon environment with the electrostatic levitation furnace (ELF) on the International Space Station (ISS). These samples were melted and gradually oxidized due to residual oxygen in the argon gas. Densities of Zr-O system with high oxygen concentration were successfully obtained, showing a negative dependence on oxygen concentration. The results show that the relationship between oxygen fraction and molar volume slightly deviates from linearity.
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  • Chihiro KOYAMA, Yuki WATANABE, Yui NAKATA, Takehiko ISHIKAWA
    2020 Volume 37 Issue 3 Pages 370303-
    Published: 2020
    Released on J-STAGE: July 31, 2020
    JOURNAL OPEN ACCESS
    The density of liquid scandium was measured using an electrostatic levitation technique. Among metal elements, scandium liquid is significantly reactive, which inhibits precise measurements of its physical properties. To resolve this problem, an electrostatic levitator was used in a vacuum on the ground. As a result, the precise density and thermal expansion were obtained and subsequently evaluated using a simple relationship between the temperature dependence of the density of a liquid metal and boiling temperature, which were founded by Steinberg. Although the previous measurement data did not conform to the Steinberg’s relationship, the data, as well as that of other metals, showed good agreement with the relationship.
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  • Hiroyuki MIYAJIMA
    2020 Volume 37 Issue 3 Pages 370304-
    Published: 2020
    Released on J-STAGE: July 31, 2020
    JOURNAL OPEN ACCESS
    The primary factors to be considered for a life support system design for long-term space habitation are mission location, mission duration, and crew size. When taking into account transportation costs and supply difficulty, a regenerative life support system and an in situ resource utilization (ISRU) system are the most important systems for long-term habitation in space and on planets. Equivalent System Mass (ESM) has been used for regenerative life support system trade studies considering biomass production (food), in other words, the degree of recycling suitable for long term missions, such as lunar and Mars missions, by NASA over the past 20 years. Therefore, we have developed a trade study tool for designing a regenerative life support system to be able to compare different systems. In this paper, a lunar farm design for six crewmembers was introduced to conduct a life support trade study on an open system, a semi-closed system, and a closed system that were designed with the tool; it indicated that it takes more than 10 years to achieve a lower cost closed system, compared to a semi-closed system.
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