Analytical protocols for Phobos regolith samples returned by the Martian Moons eXploration (MMX) mission

Earth, Planets and Space

Michael E. Zolensky¹  Yoshinori Takano²  Sara S. Russell³  Ken-ichi Bajo⁴  Yayoi N. Miura⁵  Mizuho Koike⁶  Wataru Fujiya⁷  Frederic Moynier⁸  Haruna Sugahara⁹  Tomohiro Usui⁹  Shogo Tachibana^1,10  Nancy L. Chabot^1,11  Yoshihiro Furukawa^1,12 

[1] ARES, NASA Johnson Space Center, 77058, Houston, TX, USA;Biogeochemistry Research Center, Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushima, 237-0061, Yokosuka, Japan;Department of Earth Sciences, Natural History Museum, Cromwell Road, SW7 5BD, London, UK;Department of Earth and Planetary Sciences, Hokkaido University, N10W8 Kita-ku, 060-0810, Sapporo, Japan;Earthquake Research Institute, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, 113-0032, Tokyo, Japan;Hiroshima University, 1-3-1 Kagamiyama, 739-8526, Higashihiroshima, Hiroshima, Japan;Ibaraki University, 2-1-1 Bunkyo, 310-8512, Mito, Ibaraki, Japan;Institut de Physique du Globe de Paris, CNRS, University of Paris, Paris, France;Institute of Space and Astronautical Science, JAXA, 3-1-1 Yoshinodai, 252-5210, Sagamihara, Kanagawa, Japan;Institute of Space and Astronautical Science, JAXA, 3-1-1 Yoshinodai, 252-5210, Sagamihara, Kanagawa, Japan;UTOPS, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, 113-0033, Tokyo, Japan;Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd, 20723, Laurel, MD, USA;Tohoku University, 6-3 Aza-aoba, Aramaki, Aoba-ku, 980-8578, Sendai, Japan;

关键词: MMX;    Sample analyses;    Mineralogy;    Petrology;    Chemical composition;    Isotopic composition;    Organic matter;   

DOI  :  10.1186/s40623-021-01438-9

来源: Springer

【 摘 要 】

Japan Aerospace Exploration Agency (JAXA) will launch a spacecraft in 2024 for a sample return mission from Phobos (Martian Moons eXploration: MMX). Touchdown operations are planned to be performed twice at different landing sites on the Phobos surface to collect > 10 g of the Phobos surface materials with coring and pneumatic sampling systems on board. The Sample Analysis Working Team (SAWT) of MMX is now designing analytical protocols of the returned Phobos samples to shed light on the origin of the Martian moons as well as the evolution of the Mars–moon system. Observations of petrology and mineralogy, and measurements of bulk chemical compositions and stable isotopic ratios of, e.g., O, Cr, Ti, and Zn can provide crucial information about the origin of Phobos. If Phobos is a captured asteroid composed of primitive chondritic materials, as inferred from its reflectance spectra, geochemical data including the nature of organic matter as well as bulk H and N isotopic compositions characterize the volatile materials in the samples and constrain the type of the captured asteroid. Cosmogenic and solar wind components, most pronounced in noble gas isotopic compositions, can reveal surface processes on Phobos. Long- and short-lived radionuclide chronometry such as 53Mn–53Cr and 87Rb–87Sr systematics can date pivotal events like impacts, thermal metamorphism, and aqueous alteration on Phobos. It should be noted that the Phobos regolith is expected to contain a small amount of materials delivered from Mars, which may be physically and chemically different from any Martian meteorites in our collection and thus are particularly precious. The analysis plan will be designed to detect such Martian materials, if any, from the returned samples dominated by the endogenous Phobos materials in curation procedures at JAXA before they are processed for further analyses.

【 授权许可】

CC BY