干旱区生态环境知识资源中心(Arid): Radiolytic Degradation of Soil Carbon from the Mojave Desert by Co-60 Gamma Rays: Implications for the Survival of Martian Organic Compounds Due to Cosmic Radiation

Arid

DOI	10.1089/ast.2020.2257
	Radiolytic Degradation of Soil Carbon from the Mojave Desert by Co-60 Gamma Rays: Implications for the Survival of Martian Organic Compounds Due to Cosmic Radiation
	Rojas Vivas, Jose Alfredo; Navarro-Gonzalez, Rafael; de la Rosa, Jose; Molina, Paola; Sedov, Sergey; McKay, Christopher P.
通讯作者	Navarro-Gonzalez, R (corresponding author), Univ Nacl Autonoma Mexico, Lab Quim Plasmas & Estudios Planetarios, Inst Ciencias Nucl, Circuito Exterior S-N,Ciudad Univ, Mexico City 04510, DF, Mexico.
来源期刊	ASTROBIOLOGY
ISSN	1531-1074
EISSN	1557-8070
出版年	2021
卷号	21 期号:4 页码:381-393
英文摘要	The martian surface has been continuously exposed to galactic cosmic radiation. Since organic compounds are degraded by ionizing radiation, knowledge of their decay constants is fundamental to predicting their stability on the martian surface. In this study, we report the radiolysis constant for the destruction of soil organic compounds at a starting concentration of similar to 2011 mu g C/g(soil) from the Mojave Desert. The soils were exposed to gamma irradiation with absorbed doses of up to 19 MGy at room temperature, representing similar to 250 million years of exposure to galactic cosmic rays. The destruction of total soil organic carbon and the formation of gases were investigated by a sequential on-line analytical array coupled to gas chromatography-mass spectrometry. Soil inorganic and organic carbon were degraded exponentially with a radiolysis constant 0.3 MGy(-1)(30%) producing mostly carbon dioxide (93.2%), carbon monoxide (6.2%), and methane (0.6%). Using the dose rate measured by the Radiation Assessment Detector on board the Curiosity rover, we make predictions on the survival of organic compounds in the cold martian subsurface. It is estimated that soil organic compounds with initial concentrations as those found today at the Mojave Desert would have been destroyed to levels <1 ppb at 0.1 m in depth in similar to 2000 Myr. Pristine organic compounds are expected to be present at a depth of similar to 1.5 m. These results are relevant for the search of organic compounds in past, present, and future missions to Mars. In particular, we predict that the upcoming ExoMars will encounter pristine organic compounds at this depth.
英文关键词	Carbonates Galactic cosmic rays Gamma radiation Mojave Desert Organic Compounds Soil carbon
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000601325700001
WOS关键词	MARS-LIKE SOILS ; AMINO-ACIDS ; ULTRAVIOLET-RADIATION ; IONIZING-RADIATION ; CARBOXYLIC-ACIDS ; GALE CRATER ; SURFACE ; IRRADIATION ; WATER ; MOLECULES
WOS类目	Astronomy & Astrophysics ; Biology ; Geosciences, Multidisciplinary
WOS研究方向	Astronomy & Astrophysics ; Life Sciences & Biomedicine - Other Topics ; Geology
来源机构	Universidad Nacional Autónoma de México
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/349593
作者单位	[Rojas Vivas, Jose Alfredo] Univ Nacl Autonoma Mexico, Posgrad Ciencias Tierra, Circuito Invest S-N,Ciudad Univ, Mexico City, DF, Mexico; [Rojas Vivas, Jose Alfredo; Navarro-Gonzalez, Rafael; de la Rosa, Jose; Molina, Paola] Univ Nacl Autonoma Mexico, Lab Quim Plasmas & Estudios Planetarios, Inst Ciencias Nucl, Circuito Exterior S-N,Ciudad Univ, Mexico City 04510, DF, Mexico; [Sedov, Sergey] Univ Nacl Autonoma Mexico, Dept Ciencias Ambientales & Suelo, Inst Geol, Circuito Invest S-N,Ciudad Univ, Mexico City, DF, Mexico; [McKay, Christopher P.] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA
推荐引用方式 GB/T 7714	Rojas Vivas, Jose Alfredo,Navarro-Gonzalez, Rafael,de la Rosa, Jose,et al. Radiolytic Degradation of Soil Carbon from the Mojave Desert by Co-60 Gamma Rays: Implications for the Survival of Martian Organic Compounds Due to Cosmic Radiation[J]. Universidad Nacional Autónoma de México,2021,21(4):381-393.
APA	Rojas Vivas, Jose Alfredo,Navarro-Gonzalez, Rafael,de la Rosa, Jose,Molina, Paola,Sedov, Sergey,&McKay, Christopher P..(2021).Radiolytic Degradation of Soil Carbon from the Mojave Desert by Co-60 Gamma Rays: Implications for the Survival of Martian Organic Compounds Due to Cosmic Radiation.ASTROBIOLOGY,21(4),381-393.
MLA	Rojas Vivas, Jose Alfredo,et al."Radiolytic Degradation of Soil Carbon from the Mojave Desert by Co-60 Gamma Rays: Implications for the Survival of Martian Organic Compounds Due to Cosmic Radiation".ASTROBIOLOGY 21.4(2021):381-393.