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Geoscience Frontiers 2021年第5期12卷 421-426页

作者： J.Aramendia L.Gomez-Nubla M.L.Tuite K.H.Williford K.Castro J.M.Madariaga Jet Propulsion Laboratory California Institute of Technology4800 Oak Grove DrPasadenaCA 91109United States Department of Analytical Chemistry University of the Basque Country UPV/EHUP.O.Box 64448080 BilbaoSpain

Nitrogen-containing heterocyclic compounds are fundamental biochemical components of all life on Earth and,presumably,life elsewhere in our solar system.Detection and characterization of these compounds by traditional solvent extraction,chromatographic separation,and GC-MS analysis require more sample mass than will be available from samples returned to Earth from Mars.With its small sample mass requirement,Surface Enhanced Raman Spectroscopy could be an appropriate technique for analysis of returned samples.We have developed a SERS method for the detection of maleimide(2,5-pyrroledione),an N-containing heterocycle with a structure that is widespread in biochemicals.This semi-quantitative methodology accurately determines maleimide concentration in the range from 60 mg/mL to 120 mg/mL.We present a maleimide SERS standard spectrum which will be useful as a reference for future works.The present work demonstrates an easy,accurate,and effective method for the non-destructive qualitative and semi-quantitative study of maleimide as a first step toward developing a method for analysis of related compounds.

关键词： Maleimide Surface-Enhanced Raman Spectroscopy astrobiology Biosignature Extraterrestrial life

Geomorphologic Characteristics of Polygonal Features on Chloride-Bearing Deposits on Mars: Implications for Martian Hydrology and astrobiology

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Journal of Earth Science 2019年第5期30卷 1049-1058页

作者： Binlong Ye Jun Huang Joseph Michalski Long Xiao Planetary Science Institute School of Earth Sciences China University of Geosciences Wuhan 430074 China Department of Earth Sciences and Laboratory for Space Research University of Hong Kong Hong Kong 999077 China

Over 600 chloride-bearing deposits(chlorides) have been identified on the southern highlands of Mars. These chlorides have critical implications for hydrology and astrobiology: they are indicators of an evaporating super saturated solution, and they could have provided habitat environments for halophilic microorganisms and preserved organic matter. One of the prominent geomorphology characteristics of these chloridebearing regions is the polygonal features within them. The origin of these polygonal features is still in debate. In this study, we have surveyed 153 locations of chlorides using 441 high resolution imaging science experiment(Hi RISE) images to characterize the geomorphology of polygonal features. We identified 3 types of polygonal features of distinct geomorphologic characteristics: fractures, raised ridges, and transitional polygons between fractures and raised ridges. We evaluate previously proposed hypotheses of the formation of the polygonal features, and suggest that the 3 types of polygonal features are indicators of different stages of salt crust formation. Salt crust is usually formed through multiple groundwater activities, and it often occurs in playa environment on Earth. The unique hydrological and astrobiological implications of the chlorides with polygonal features make these deposits of high priority for future landed on and/or sample return exploration missions of Mars.

关键词： chlorides polygonal feature playa hydrology astrobiology Mars

Distribution characteristics of lipids from salt sediments in Qaidam Basin and their astrobiological significance

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Science China Earth Sciences 2022年第1期65卷 156-166页

作者： Ziye CHENG Long XIAO Hongmei WANG Ting HUANG School of Geography and Tourism Guangdong University of Finance and EconomicsGuangzhou 510320China State Key Laboratory of Geological Processes and Mineral Resources Planetary Science InstituteChina University of GeosciencesWuhan 430074China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyMacao 999078China

On Earth,salt environments are the most relevant analogues to Martian salt deposits with regard to the search for preserved biomolecules.In this study,we analyzed the distribution of lipids in salt samples from Dalangtan and Qarhan in the Qaidam Basin,which is the most important area to carry out analog research of Mars in China.Furthermore,we compared the lipids distribution results with that from other typical Martian analog sites such as the Atacama Desert.Salt samples in the Qaidam Basin are enriched with fatty acid compounds,including normal fatty acids,unsaturated fatty acids,branched fatty acids,and acyclic isoprene acids.In addtion,glycerol dialkyl glycerol tetraethers(GDGTs)and archaeol compounds were also detected in these salt samples.Compared with the hypersaline samples,the clay samples not only have higher abuandance of fatty acids,GDGTs and archaeol compounds,but also a more diversed lipids composition.Only a few lipids were detected in the pure-saline samples,such as archaeol compounds.These clues suggest that content of salt minerals is the major factor affecting the distribution of lipids.This study provides an analogy for detecting and evaluating the traces of life that may exist on Mars.

关键词： Salt sediments Lipids astrobiology The Qaidam Basin Mars

Shallow subsurface habitats across the Mars-analog Qaidam Basin

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Science China Earth Sciences 2023年第11期66卷 2487-2496页

作者： Yan CHEN Li LIU Huiqing ZHANG Xue GUO Wensi ZHANG Chunxia ZHANG Wei LIN Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Clinical Laboratory National Clinical Research Center for Infectious DiseaseShenzhen Third People’s HospitalShenzhen 518112China State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

Searching for life is one of the most important targets of Mars exploration missions. It has been considered that the Martian subsurface, away from the extreme surface environment, is a potentially habitable region for microbial growth.However, the distribution pattern of potential microbial habitats in the Martian subsurface has yet to be evaluated. Here, we investigate the subsurface habitats to depths of 20–60 cm from various landscapes, including slopes, gullies, channels, playas,and alluvial fans across the Mars-analog Qaidam Basin, NW China. We characterize subsurface niches by measuring microbial biomass and radiocarbon ages, and correlate them with soil properties including depth, moisture content, total organic carbon content, electric conductivity, pH, evaporite and clay mineral contents. We find more habitable niches for microbial colonization at depths of 5–25 cm as compared with the surface and deep subsurface across the hyperarid Qaidam Basin. Maximum biomass and biotic activity could be correlated with physical stability, limited radiation, and short-term moderate water availability in the shallow subsurface in hyperarid deserts. The findings of this study provide new perspectives on subsurface microbial habitats in Mars-analog hyperarid deserts and ongoing biosignature detection on Mars.

关键词： Mars-analog Qaidam Basin Shallow subsurface Microbial habitat astrobiology

Mapping of Compositional Diversity and Chronological Ages of Lunar Farside Multiring Mare Moscoviense Basin:Implications to the Middle Imbrian Mare Basalts

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Research in Astronomy and Astrophysics 2022年第12期22卷 130-151页

作者： A.Karthi S.Arivazhagan Manish Sharma Centre for Applied Geology The Gandhigram Rural Institute—Deemed to be UniversityGandhigramDindigul-624302Tamil NaduIndia College of Natural and Health Sciences Zayed UniversityP.O.Box 144534Abu DhabiUnited Arab Emirates

The Mare Moscoviense is an astonishing rare flatland multi-ring basin and one of the recognizable mare regions on the Moon's farside.The mineralogical,chronological,topographical and morphological studies of the maria surface of the Moon provide a primary understanding of the origin and evolution of the mare provinces.In this study,the Chandrayaan-1 M^(3)data have been employed to prepare optical maturity index,FeO and TiO^(2)concentration,and standard band ratio map to detect the mafic indexes like olivine and pyroxene minerals.The crater size frequency distribution method has been applied to LROC WAC data to obtain the absolute model ages of the Moscoviense basin.The four geological unit ages were observed as 3.57 Ga(U-2),3.65 Ga(U-1),3.8 Ga(U-3)and 3.92 Ga(U-4),which could have been formed between the Imbrian and Nectarian epochs.The M^(3)imaging and reflectance spectral parameters were used to reveal the minerals like pyroxene,olivine,ilmenite,plagioclase,orthopyroxene-olivine-spinel lithology,and olivine-pyroxene mixtures present in the gabbroic basalt,anorthositic and massive ilmenite rocks,and validated with the existing database.The results show that the Moscoviense basin is dominated by intermediate TiO^(2)basalts that derived from olivine-ilmenite-pyroxene cumulate depths ranging from 200 to 500 km between 3.5 Ga and 3.6 Ga.

关键词： astrobiology molecular processes methods:data analysis techniques:image processing techniques:imaging spectroscopy techniques:spectroscopic planets and satellites:composition planets and satellites:surfaces planets and satellites:terrestrial planets

Theoretical approach to study the formation of C2H4O2 isomers in interstellar medium through reaction between interstellar formaldehyde molecules

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Research in Astronomy and Astrophysics 2020年第1期20卷 124-136页

作者： Aftab Ahmad Shivani Alka Misra Poonam Tandon Department of Mathematics&Astronomy University of LucknowLucknowIndia Department of Physics University of LucknowLucknowIndia

The three isomers of C2H4O2,viz.,glycolaldehyde(HCOCH2 OH),acetic acid(CH3 COOH)and methyl formate(HCOOCH3),have been detected in copious amounts in the interstellar medium(ISM).The possibility for formation of these molecules through interstellar formaldehyde(HCHO)has been explored by using the quantum chemical approach described by density functional theory(DFT)and second order Moller-Plesset perturbation(MP2)theory with a 6–311 G(d,p)basis set in the gas phase as well as in icy grains.The associated molecule-molecule interactions have been discussed to study the formation of isomers of C2H4O2 in ISM.The reactions of two formaldehyde molecules exhibit a considerable potential barrier but due to quantum tunneling,these reactions could be possible in ISM.The chemical pathway is exothermic,which gives rise to a high probability for the formation of all three isomers,viz.glycolaldehyde,methyl formate and acetic acid,in interstellar space.Anharmonic rotational vibration,centrifugal distortion constants and coupling constants are also calculated and results suggest that the vibrations are harmonic in nature.

关键词： ISM:molecules astrochemistry astrobiology abundances

Enigmatic Glass-Like Carbon from the Alpine Foreland, Southeast Germany: A Natural Carbonization Process

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2179-2200页

作者： Tatyana G. SHUMILOVA Sergey I. ISAENKO Vasily V. ULYASHEV Boris A. MAKEEV Michael A. RAPPENGLüCK Aleksey A. VELIGZHANIN Kord ERNSTSON Institute of Geology of Komi Scientific Center of Ural Branch of Russian Academy of Sciences Pervomayskaya st.54Syktyvkar167982Russia Hawaii Institute of Geophysics and Planetology University of Hawaii at Manoa1680 East-West RoadHonoluluHI96822USA Institute for Interdisciplinary Studies GilchingGermany National Research Center 《Kurchatov Institute》 Akademika Kurchatova pl.1Moscow123182Russia Faculty of Philosophy I University of WürzburgGermany

Unusual carbonaceous matter, termed here chiemite, composed of more than 90% C from the Alpine Foreland at Lake Chiemsee in Bavaria, southeastern Germany has been investigated using optical and atomic force microscopy, X-ray fluorescence spectroscopy, scanning and transmission electron microscopy, high-resolution Raman spectroscopy, X-ray diffraction and differential thermal analysis, as well as by δ13 C and 14 C radiocarbon isotopic data analysis. In the pumice-like fragments, poorly ordered carbon matter co-exists with high-ordering monocrystalline α-carbyne, and contains submicrometersized inclusions of complex composition. Diamond and carbyne add to the peculiar mix of matter. The required very high temperatures and pressures for carbyne formation point to a shock event probably from the recently proposed Holocene Chiemgau meteorite impact. The carbon material is suggested to have largely formed from heavily shocked coal, vegetation like wood, and peat from the impact target area. The carbonization/coalification high PT process may be attributed to a strong shock that instantaneously caused the complete evaporation and loss of volatile matter and water, which nevertheless preserved the original cellular structure seen fossilized in many fragments. Relatively fresh wood encapsulated in the purported strongly shocked matter point to quenched carbon melt components possibly important for the discussion of survival of organic matter in meteorite impacts, implying an astrobiological relationship.

关键词： astrobiology diamond carbyne coalification carbonization meteorite impact chiemite

Origins of building blocks of life: A review

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Geoscience Frontiers 2018年第4期9卷 1117-1153页

作者： Norio Kitadai Shigenori Maruyama Earth-Life Science Institute Tokyo Institute of Technology

How and where did life on Earth originate？ To date, various environments have been proposed as plausible sites for the origin of life. However, discussions have focused on a limited stage of chemical evolution, or emergence of a specific chemical function of proto-biological systems. It remains unclear what geochemical situations could drive all the stages of chemical evolution, ranging from condensation of simple inorganic compounds to the emergence of self-sustaining systems that were evolvable into modern biological ones. In this review, we summarize reported experimental and theoretical findings for prebiotic chemistry relevant to this topic, including availability of biologically essential elements（N and P） on the Hadean Earth, abiotic synthesis of life＇s building blocks（amino acids, peptides, ribose, nucleobases, fatty acids, nucleotides, and oligonucleotides）, their polymerizations to bio-macromolecules（peptides and oligonucleotides）, and emergence of biological functions of replication and compartmentalization. It is indicated from the overviews that completion of the chemical evolution requires at least eight reaction conditions of（1） reductive gas phase,（2） alkaline pH,（3） freezing temperature,（4）fresh water,（5） dry/dry-wet cycle,（6） coupling with high energy reactions,（7） heating-cooling cycle in water, and（8） extraterrestrial input of life＇s building blocks and reactive nutrients. The necessity of these mutually exclusive conditions clearly indicates that life＇s origin did not occur at a single setting; rather, it required highly diverse and dynamic environments that were connected with each other to allow intratransportation of reaction products and reactants through fluid circulation. Future experimental research that mimics the conditions of the proposed model are expected to provide further constraints on the processes and mechanisms for the origin of life.

关键词： astrobiology Biochemistry Chemical evolution Extraterrestrial life Hadean Earth Hydrothermal systems

Karite-diamond fossil:A new type of natural diamond

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Geoscience Frontiers 2020年第4期11卷 1163-1174页

作者： T.G.Shumilova V.V.Ulyashev V.A.Kazakov S.I.Isaenko S.A.Svetov S.Yu.Chazhengina N.S.Kovalchuk Institute of Geology of Komi Scientific Centre of the Ural Branch of the Russian Academy of Sciences Pervomayskaya St.54Syktyvkar167982Russia Hawaii Institute of Geophysics and Planetology University of Hawaii at Manoa1680 East-West RoadHonoluluHI96822USA SSC FSUE Keldysh Research Centre Onezhskaya8125438MoscowRussia Institute of Geology of the Karelian Research Centre of the Russian Academy of Sciences Petrozavodsk11 Pushkinskaya StreetRussia

Impact diamond is one of perspective natural type of superhard carbon materials,forming huge resources sometimes,such as Popigai impact structure counting the largest diamond storage on the Earth.By present,there are two known types of impact diamonds-after-graphitic and after-coal varieties formed from different carbon precursors.Here we present for the first time a new impact diamond type-diamond fossils,named by "karite",formed about 70 Ma from unmetamorphosed organics in the giant Kara impact crater(Pay-Khoy,Russia).A full complex of the diamond fossil characteristics is described proving its nature and phase state.Karite is presented with supernanocrystalline diamond aggregates,nicely preserves tiny cell morphology and relict features of lignin and cellulose.The diamond fossils are spread widely through the Kara impactites,point to possible wider distribution of impact diamonds within large impact occurrences around the world,can be used for impact modeling,astrobiological and material studies.

关键词： Astroblemes Impact diamonds Fossils Diamond paramorphs astrobiology

Planetary Heating by Neutrinos: Long-Term Habitats for Aquatic Life if Dark Energy Decays Favourably

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Journal of Modern Physics 2013年第12期4卷 20-47页

作者： R. J. Spivey School of Biological Sciences Bangor University Bangor United Kingdom

The potential cosmological and astrobiological implications of neutrinos are considered. Dark energy drives the current phase of accelerating cosmic expansion. Like inflation, it may decay in time to matter and radiation. However, since its energy density is minuscule in comparison, decay would be unlikely to inject such a rich variety of particles into the universe, and may instead be limited to the lowest energy fermions. Nonrelativistic neutrinos have the capacity to form stable, galaxy-engulfing haloes supported by degeneracy pressure, much like white dwarves and neutron stars. Conversely, bodies of mass can indefinitely rely on Coulomb forces for weight support. Opportunities for the mutual annihilation of electron neutrinos are largely confined to planets containing iron in the hcp phase. If dark energy decays primarily to neutrinos in 40 ~ 100 Gyr, then oceanic planets orbiting within the resulting haloes could provide long-term habitats for aquatic life with only lax constraints on the neutrino mass, . Various considerations now favour the possibility that neutrinos are Majorana particles with an inverted mass hierarchy and an electron neutrino mass in the vicinity of 50 meV. Sterile neutrinos of eV-mass may already be a significant component of dark matter, and could enhance planetary heating when active neutrino haloes become heavily depleted. An intriguing mechanism capable of regulating oceanic heat flux over a wide range of planetary masses is also described.

关键词： Neutrinos Dark Matter Dark Energy Sterile Neutrinos Oceanic Planets astrobiology Cosmology