62 results on '"Michel Nuevo"'
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2. Monosaccharides and Their Derivatives in Carbonaceous Meteorites: A Scenario for Their Synthesis and Onset of Enantiomeric Excesses
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George Cooper, Andro C. Rios, and Michel Nuevo
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carbonaceous meteorites ,interstellar photolysis ,enantiomeric excess ,monosaccharide ,sugars ,sugar acid ,aldoses ,aldonic acid ,sugar alcohol ,glycerol ,Science - Abstract
Carbonaceous meteorites provide the best glimpse into the solar system’s earliest physical and chemical processes. These ancient objects, ~4.56 billion years old, contain evidence of phenomena ranging from solar system formation to the synthesis of organic compounds by aqueous and (likely) low-temperature photolytic reactions. Collectively, chemical reactions resulted in an insoluble kerogen-like carbon phase and a complex mixture of discrete soluble compounds including amino acids, nucleobases, and monosaccharide (or “sugar”) derivatives. This review presents the documented search for sugars and their derivatives in carbonaceous meteorites. We examine early papers, published in the early 1960s, and note the analytical methods used for meteorite analysis as well as conclusions on the results. We then present the recent finding of sugar derivatives including sugar alcohols and several sugar acids: The latter compounds were found to possess unusual “d” enantiomeric (mirror-image) excesses. After discussions on the possible roles of interstellar grain chemistry and meteorite parent body aqueous activity in the synthesis of sugar derivatives, we present a scenario that suggests that most of Earth’s extraterrestrial sugar alcohols (e.g., glycerol) were synthesized by interstellar irradiation and/or cold grain chemistry and that the early solar disk was the location of the initial enantiomeric excesses in meteoritic sugar derivatives.
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- 2018
- Full Text
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3. The Nature of Insoluble Organic Matter in Sutter’s Mill and Murchison Carbonaceous Chondrites: Testing the Effect of X-ray Computed Tomography (XCT) and Exploring Parent Body Organic Molecular Evolution
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George D. Cody, Conel M. O'D. Alexander, Dionysis I. Fostoukos, Henner Busemann, Scott Eckley, Aaron S. Burton, Eve L. Berger, Michel Nuevo, Scott A. Sandford, Daniel P. Glavin, Jason P. Dworkin, Harold C. Connolly Jr, and Dante S. Lauretta
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Lunar and Planetary Science and Exploration - Abstract
This study analyzed samples of the Murchison and Sutter’s Mill carbonaceous chondrite meteorites in support of the future analysis of samples returned from the asteroid (10155) Bennu by the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer) mission. Focusing specifically on the insoluble organic matter (IOM), this study establishes that a total of 1.3 g of bulk sample from a single chondritic meteorite is sufficient to obtain a wide range of cosmochemical information, including light element analysis (H, C, and N), isotopic analysis (D/H, 13C/12C, and 15N/14N), and X-ray fluorescence spectroscopy for major elemental abundances. IOM isolated from the bulk meteorite samples was analyzed by light element and isotopic analysis as described above, 1H and 13C solid-state nuclear magnetic resonance spectroscopy, Raman spectroscopy, and complete noble gas analyses (abundances and isotopes). The samples studied included a pair from Murchison (CM2), one of which had been irradiated with high-energy X-rays in the course of computed tomographic imaging. No differences between the irradiated and non-irradiated Murchison samples were observed in the many different chemical and spectroscopic analyses, indicating that any X-ray–derived sample damage is below levels of detection. Elemental, isotopic, and molecular spectroscopic data derived from IOM isolated from the Sutter’s Mill sample reveals evidence that this meteorite falls into the class of heated CM chondrites.
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- 2023
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4. Astrobiology on Mars: Organic Chemical Evolution on an Earth-like Planet
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Alfonso Davila, Morgan Cable, David Catling, James Cleaves, Jennifer L Eigenbrode, Devan Nission, Michel Nuevo, Sarah Johnson, Andrew Steele, and Jennifer Stern
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Exobiology - Abstract
This white paper recommends that the next decade of Mars exploration prioritizes research into the chemistry, distribution, and origin of organic matter in martian geologic materials, both in situand in samples returned to Earth
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- 2020
5. The Photochemistry of Purine in Ice Analogs Relevant to Dense Interstellar Clouds
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Christopher K Materese, Michel Nuevo, Brittiana L McDowell, Christina E Buffo, and Scott A Sandford
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Astrophysics - Abstract
The aromatic nitrogen heterocyclic compound purine is the core structural framework of many important biomolecules, particularly nucleobases. Purine and purine derivatives have been observed in carbonaceous chondrites, and it has been hypothesized that the exogenous delivery of these compounds, along with many other biologically relevant compounds, may have played a role in the emergence of life. Numerous experiments in our laboratory have demonstrated that the nucleobases used by life to encode genetic material could have been produced abiotically under astrophysically relevant conditions. Specifically, the UV photoprocessing of pyrimidine and purine in simple ices of astrophysical interest has resulted in the production of all five biological nucleobases, namely, uracil (RNA), cytosine (RNA and DNA), thymine (DNA), adenine (RNA and DNA), and guanine (RNA and DNA). Additionally, follow-up work has examined the photochemistry of pyrimidine in more complex astrophysical ice mixtures to better understand the formation of these compounds under realistic conditions. In this work, we examine the photochemistry of purine in more complex ices of astrophysical interest and compare our results with those from simpler ice mixtures. We also examine the effects of competing parallel synthesis of organic compounds in the ices (unrelated to purine). Finally, we discuss the astrophysical and astrobiological implications of our findings.
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- 2018
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6. The Production and Potential Detection of Hexamethylenetetramine-Methanol in Space
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Michel Nuevo, Scott A. Sandford, Christopher K. Materese, Partha P. Bera, and Timothy J. Lee
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Extraterrestrial Environment ,010504 meteorology & atmospheric sciences ,Methanol ,Photodissociation ,Infrared spectroscopy ,Vibration ,01 natural sciences ,Agricultural and Biological Sciences (miscellaneous) ,Spectral line ,chemistry.chemical_compound ,Crystallography ,chemistry ,Space and Planetary Science ,Ab initio quantum chemistry methods ,Exobiology ,0103 physical sciences ,Molecule ,Irradiation ,Hexamethylenetetramine ,Methenamine ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences - Abstract
Numerous laboratory studies of astrophysical ice analogues have shown that their exposure to ionizing radiation leads to the production of large numbers of new, more complex compounds, many of which are of astrobiological interest. We show here that the irradiation of astrophysical ice analogues containing H2O, CH3OH, CO, and NH3 yields quantities of hexamethylenetetramine-methanol (hereafter HMT-methanol; C7N4H14O) that are easily detectible in the resulting organic residues. This molecule differs from simple HMT, which is known to be abundant in similar ice photolysis residues, by the replacement of a peripheral H atom with a CH2OH group. As with HMT, HMT-methanol is likely to be an amino acid precursor. HMT has tetrahedral (Td) symmetry, whereas HMT-methanol has C1 symmetry. We report the computed expected infrared spectra for HMT and HMT-methanol obtained using ab initio quantum chemistry methods and show that there is a good match between the observed and computed spectra for regular HMT. Since HMT-methanol lacks the high symmetry of HMT, it produces rotational transitions that could be observed at longer wavelengths, although establishing the exact positions of these transitions may be challenging. It is likely that HMT-methanol represents an abundant member of a larger family of functionalized HMT molecules that may be present in cold astrophysical environments.
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- 2020
7. Prebiotic Astrochemistry and the Formation of Molecules of Astrobiological Interest in Interstellar Clouds and Protostellar Disks
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Partha P. Bera, Timothy J. Lee, Scott A. Sandford, and Michel Nuevo
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Evolution, Chemical ,Astrochemistry ,Extraterrestrial Environment ,010405 organic chemistry ,Chemistry ,Interstellar cloud ,Meteoroids ,General Chemistry ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Astrobiology ,Exobiology ,Molecule - Abstract
Despite the generally hostile nature of the environments involved, chemistry does occur in space. Molecules are seen in environments that span a wide range of physical and chemical conditions and that clearly were created by a multitude of chemical processes, many of which differ substantially from those associated with traditional equilibrium chemistry. The wide range of environmental conditions and processes involved with chemistry in space yields complex populations of materials, and because the elements H, C, O, and N are among the most abundant in the universe, many of these are organic in nature, including some of direct astrobiological interest. Much of this chemistry occurs in "dense" interstellar clouds and protostellar disks surrounding forming stars because these environments have higher relative densities and more benign radiation fields than in stellar ejectae or the diffuse interstellar medium. Because these are the environments in which new planetary systems form, some of the chemical species made in these environments are expected to be delivered to the surfaces of planets where they can potentially play key roles in the origin of life. Because these chemical processes are universal and should occur in these environments wherever they are found, this implies that some of the starting materials for life are likely to be widely distributed throughout the universe.
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- 2020
8. Mid‐infrared study of stones from the Sutter's Mill meteorite
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Michel Nuevo, Scott A. Sandford, George J. Flynn, and Susan Wirick
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- 2014
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9. Formation of complex organic molecules in astrophysical environments: Sugars and derivatives
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Christina E. Buffo, George Cooper, Michel Nuevo, John M. Saunders, and Scott A. Sandford
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chemistry.chemical_classification ,0303 health sciences ,Astrochemistry ,Astronomy and Astrophysics ,medicine.disease_cause ,01 natural sciences ,Sugar acids ,Amino acid ,Nucleobase ,03 medical and health sciences ,chemistry ,Meteorite ,Space and Planetary Science ,0103 physical sciences ,Amphiphile ,medicine ,Organic chemistry ,Sugar ,010303 astronomy & astrophysics ,Ultraviolet ,030304 developmental biology - Abstract
Carbonaceous meteorites contain a large variety of complex organic molecules, including amino acids, nucleobases, sugar derivatives, amphiphiles, and other compounds of astrobiological interest. Photoprocessing of ices condensed on cold grains with ultraviolet (UV) photons was proposed as an efficient way to form such complex organics in astrophysical environments. This hypothesis was confirmed by laboratory experiments simulating photo-irradiation of ices containing H2O, CH3OH, CO, CO2, CH4, H2CO, NH3, HCN, etc., condensed on cold (~10–80 K) substrates. These experiments resulted in the formation of amino acids, nucleobases, sugar derivatives, amphiphilic compounds, and other organics comparable to those identified in carbonaceous meteorites. This work presents results for the formation of sugars, sugar alcohols, sugar acids, and their deoxy variants from the UV irradiation of ices containing H2O and CH3OH in relative proportions 2:1, and their comparison with meteoritic data. The formation mechanisms of these compounds and the astrobiological implications are also discussed.
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- 2019
10. Deoxyribose and deoxysugar derivatives from photoprocessed astrophysical ice analogues and comparison to meteorites
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Scott A. Sandford, Michel Nuevo, and George Cooper
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0301 basic medicine ,Science ,General Physics and Astronomy ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Article ,Nucleobase ,03 medical and health sciences ,chemistry.chemical_compound ,0103 physical sciences ,Ribose ,Organic chemistry ,lcsh:Science ,Sugar ,010303 astronomy & astrophysics ,Multidisciplinary ,General Chemistry ,Sugar derivatives ,030104 developmental biology ,chemistry ,Meteorite ,Deoxyribose ,Ultraviolet irradiation ,lcsh:Q ,DNA - Abstract
Sugars and their derivatives are essential to all terrestrial life. Their presence in meteorites, together with amino acids, nucleobases, amphiphiles, and other compounds of biological importance, may have contributed to the inventory of organics that played a role in the emergence of life on Earth. Sugars, including ribose (the sugar of RNA), and other sugar derivatives have been identified in laboratory experiments simulating photoprocessing of ices under astrophysical conditions. In this work, we report the detection of 2-deoxyribose (the sugar of DNA) and several deoxysugar derivatives in residues produced from the ultraviolet irradiation of ice mixtures consisting of H2O and CH3OH. The detection of deoxysugar derivatives adds to the inventory of compounds of biological interest that can form under astrophysical conditions and puts constraints on their abiotic formation pathway. Finally, we report that some of the deoxysugar derivatives found in our residues are also newly identified in carbonaceous meteorites., Sugars are known to form from the UV photoprocessing of ices under astrophysical conditions. Here, the authors report the detection of deoxyribose, the sugar of DNA, and other deoxysugars from the UV photoprocessing of H2O:CH3OH ice mixtures, which are compared with materials from carbonaceous meteorites.
- Published
- 2018
11. Beyond targeted searches: the need for system-level approaches to understanding the connection between astrochemistry and the emergence of life
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Lynn J. Rothschild, Andro C. Rios, David Summers, Mark A. Ditzler, Michel Nuevo, Rocco L. Mancinelli, Arthur L. Weber, Milena Popović, and Jared T. Broddrick
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Computer science ,System level ,Data science ,Connection (mathematics) - Published
- 2021
12. Abzu: Uncovering the Origin of Ancient Organics on Mars
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Jessica E. Koehne, Leslie Radosevich, Anuscheh Nawaz, P. Michael Furlong, Paul R. Mahaffy, Evan Eshelman, Mary Beth Wilhelm, Lauren Friend, Pablo Sobron, Trey Smith, Michel Nuevo, Thomas McClure, Dave Des Marais, R. Williams, Linda L. Jahnke, Jay Bookbinder, Alexis Rodriguez, Kanch Sridhar, Mark A. Ditzler, Jennifer G. Blank, Abraham Rademacher, Spencer Baird, Goro Komatsu, Jennifer L. Eigenbrode, Dorothy Z. Oehler, Tori N. Chinn, Antonio J. Ricco, Morgan J. Anderson, Michael Bicay, Matthew Chin, Travis Boone, Terry Fong, Trinh Hoac, Denise Buckner, Thomas W. Evans, and Adrian E. Southard
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Mars Exploration Program ,Geology ,Astrobiology - Published
- 2021
13. Critical Laboratory Studies to Advance Planetary Science and Support Missions
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Murthy S. Gudipati, Morgan L. Cable, Jürgen Blum, Silvia Protopapa, Aaron Noell, Stefanie N. Milam, Michel Nuevo, Baptiste Journaux, Edith C. Fayolle, Jennifer Hanley, Laurie Barge, Rachel L. Smith, Jessica M. Weber, Farid Salama, Sarah E. Waller, Mohit Melwani Daswani, Jason P. Dworkin, Bryana L. Henderson, Chris J. Bennett, Ella Sciamma-O'Brien, and Brian J. Drouin
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Earth and Planetary Astrophysics (astro-ph.EP) ,Engineering ,Planetary science ,business.industry ,FOS: Physical sciences ,Astrophysics - Instrumentation and Methods for Astrophysics ,business ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics - Earth and Planetary Astrophysics ,Astrobiology - Abstract
Laboratory studies for planetary science and astrobiology aimat advancing our understanding of the Solar System through the promotion of theoretical and experimental research into the underlying processes that shape it. Laboratory studies (experimental and theoretical) are crucial to interpret observations and mission data, and are key incubators for new mission concepts as well as instrument development and calibration. They also play a vital role in determining habitability of Solar System bodies, enhancing our understanding of the origin of life, and in the search for signs of life beyond Earth, all critical elements of astrobiology. Here we present an overview of the planetary science areas where laboratory studies are critically needed, in particular in the next decade. These areas include planetary & satellites atmospheres, surfaces, and interiors, primitive bodies such as asteroids, meteorites, comets, and trans-Neptunian objects, and signs of life. Generating targeted experimental and theoretical laboratory data that are relevant for a better understanding of the physical, chemical, and biological processes occurring in these environments is crucial. For each area we present i) a brief overview of the state-of-the-art laboratory work, ii) the challenges to analyze and interpret data sets from missions and ground-based observations and to support mission and concept development, and iii) recommendations for high priority laboratory studies., White paper submitted to the Planetary Science Decadal Survey 2013-2022
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- 2021
14. Optical Constants of Outer Solar System Materials and Radiative Transfer Modeling
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Chloe B. Beddingfield, Joseph E. Roser, Michel Nuevo, Tanguy Bertrand, Francesca Scipioni, Yvonne J. Pendleton, Ted L. Roush, Dale P. Cruikshank, Ella Sciamma-O'Brien, Cristina M. Dalle Ore, and Richard Cartwright
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Solar System ,Materials science ,Radiative transfer modeling ,Computational physics - Published
- 2021
15. The Titan Haze Simulation (THS) experiment on COSmIC. Part III. XANES study of laboratory analogs of Titan tholins
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Michel Nuevo, Ella Sciamma-O’Brien, Scott A. Sandford, Farid Salama, Christopher K. Materese, and A.L. David Kilcoyne
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Space and Planetary Science ,Astronomy and Astrophysics - Published
- 2022
16. ICE CHEMISTRY ON OUTER SOLAR SYSTEM BODIES: ELECTRON RADIOLYSIS OF N
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Christopher K, Materese, Dale P, Cruikshank, Scott A, Sandford, Hiroshi, Imanaka, and Michel, Nuevo
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Article - Abstract
Radiation processing of the surface ices of outer Solar System bodies may be an important process for the production of complex chemical species. The refractory materials resulting from radiation processing of known ices are thought to impart to them a red or brown color, as perceived in the visible spectral region. In this work, we analyzed the refractory materials produced from the 1.2-keV electron bombardment of low-temperature N(2)-, CH(4)-, and CO-containing ices (100:1:1), which simulates the radiation from the secondary electrons produced by cosmic ray bombardment of the surface ices of Pluto. Despite starting with extremely simple ices dominated by N(2), electron irradiation processing results in the production of refractory material with complex oxygen- and nitrogen-bearing organic molecules. These refractory materials were studied at room temperature using multiple analytical techniques including Fourier-transform infrared spectroscopy, X-ray absorption near-edge structure (XANES) spectroscopy, and gas chromatography coupled with mass spectrometry (GC-MS). Infrared spectra of the refractory material suggest the presence of alcohols, carboxylic acids, ketones, aldehydes, amines, and nitriles. XANES spectra of the material indicate the presence of carboxyl groups, amides, urea, and nitriles, and are thus consistent with the IR data. Atomic abundance ratios for the bulk composition of these residues from XANES analysis show that the organic residues are extremely N-rich, having ratios of N/C ~ 0.9 and O/C ~ 0.2. Finally, GC-MS data reveal that the residues contain urea as well as numerous carboxylic acids, some of which are of interest for prebiotic and biological chemistries.
- Published
- 2020
17. The Formation of Nucleobases from the Ultraviolet Photoirradiation of Purine in Simple Astrophysical Ice Analogues
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Scott A. Sandford, Christopher K. Materese, and Michel Nuevo
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Purine ,010504 meteorology & atmospheric sciences ,Pyrimidine ,Ultraviolet Rays ,Guanine ,Stereochemistry ,01 natural sciences ,Article ,Nucleobase ,chemistry.chemical_compound ,Exobiology ,0103 physical sciences ,Uracil ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Ice ,Purine Nucleosides ,Agricultural and Biological Sciences (miscellaneous) ,Thymine ,chemistry ,Purines ,Space and Planetary Science ,Cytosine ,DNA - Abstract
Nucleobases are the informational subunits of RNA and DNA and are essential to all known forms of life. The nucleobases can be divided into two groups of molecules: the pyrimidine-based compounds that include uracil, cytosine, and thymine, and the purine-based compounds that include adenine and guanine. Previous work in our laboratory has demonstrated that uracil, cytosine, thymine, and other nonbiological, less common nucleobases can form abiotically from the UV photoirradiation of pyrimidine in simple astrophysical ice analogues containing combinations of H2O, NH3, and CH4. In this work, we focused on the UV photoirradiation of purine mixed with combinations of H2O and NH3 ices to determine whether or not the full complement of biological nucleobases can be formed abiotically under astrophysical conditions. Room-temperature analyses of the resulting photoproducts resulted in the detection of adenine, guanine, and numerous other functionalized purine derivatives. Key Words: Pyrimidine-Nucleobases-Interstellar; Ices-Cometary; Ices-Molecular processes-Prebiotic chemistry. Astrobiology 17, 761-770.
- Published
- 2017
18. Mid-infrared study of stones from the Sutter's Mill meteorite
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Susan Wirick, George J. Flynn, Scott A. Sandford, and Michel Nuevo
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Murchison meteorite ,chemistry.chemical_compound ,Geophysics ,chemistry ,Meteorite ,Space and Planetary Science ,Infrared ,Mineralogy ,Infrared spectroscopy ,Carbonate ,Spectral resolution ,Fourier transform infrared spectroscopy ,Spectroscopy - Abstract
The Sutter's Mill meteorite fell in northern California on April 22, 2012, and numerous pieces have been recovered and studied with several analytical techniques [1]. We present a Fourier-transform infrared (FTIR) spectroscopy analysis of fragments from several stones of the meteorite. Methods and analysis: Infrared spectra of samples SM2 and SM12 were recorded with a Nicolet iN10 MX FTIR microscope in the mid-IR range (4000-650/cm; spectral resolution 4/cm), while samples SM20 and SM30 were analyzed with a synchrotron-based Nicolet Continuum IR microscope in the same range. Samples were deposited on a clean glass slide, crushed with either a stainless steel roller tool or between 2 slides, and placed directly on the focal plane of the microscopes. Results: IR spectra of non-fusion crust samples show several absorption features associated with minerals such as olivines, phyllosilicates, carbonates (calcite and dolomite), and pyroxenes, as well as organics [2]. The carbonates display a main, broad band centered at 1433/cm, with additional bands at 2515/cm, 1797/cm, 882/cm, and 715/cm. Features associated with phyllosilicates include a symmetric Si-O stretching mode band centered at 1011/cm and several O-H stretching mode bands―a broad band centered at 3415/cm that is probably due to adsorbed H2O, and occasionally a much weaker, narrower feature centered near 3680/cm due to structural O-H. Features observed in the 2985-2855/cm range suggest the presence of aliphatic -CH3 and -CH2- groups. However, some of these bands show unusual relative intensities, mainly because of carbonate overtone bands that fall in the same spectral range, which can make the identification of C-H stretching bands problematic. The positions and relative strengths of the aliphatic -CH2- and -CH3 features, where they can be distinguished from overlapping carbonate bands, are consistent with those in interplanetary dust particles (IDPs) and Murchison. Finally, the absence of a strong C=O absorption feature near 1700/cm distinguishes the organics in the Sutter's Mill meteorite from that in most IDPs and in Murchison, but is consistent with the organic matter in Tagish Lake.
- Published
- 2014
19. Irradiation of Pyrimidine in Pure H2O Ice with High-Energy Ultraviolet Photons
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T. S. Yih, C. Y. Robert Wu, Wei Jie Hu, Jun Ming Qiu, Hok Sum Fung, Michel Nuevo, C. C. Chu, Wing-Huen Ip, Y.-J. Chen, and Shang Ruei Wu
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Spectrophotometry, Infrared ,Pyrimidine ,Ultraviolet Rays ,Analytical chemistry ,Infrared spectroscopy ,medicine.disease_cause ,Photochemistry ,Gas Chromatography-Mass Spectrometry ,Nucleobase ,chemistry.chemical_compound ,medicine ,Irradiation ,Chromatography, High Pressure Liquid ,Research Articles ,Photons ,Ice ,Uracil ,Agricultural and Biological Sciences (miscellaneous) ,Thymine ,Pyrimidines ,chemistry ,Space and Planetary Science ,Synchrotrons ,Ultraviolet ,Cytosine ,Half-Life - Abstract
The detection of nucleobases, the informational subunits of DNA and RNA, in several meteorites suggests that these compounds of biological interest were formed via astrophysical, abiotic processes. This hypothesis is in agreement with recent laboratory studies of irradiation of pyrimidine in H2O-rich ices with vacuum UV photons emitted by an H2-discharge lamp in the 6.9–11.3 eV (110–180 nm) range at low temperature, shown to lead to the abiotic formation of several compounds including the nucleobases uracil, cytosine, and thymine. In this work, we irradiated H2O:pyrimidine ice mixtures under astrophysically relevant conditions (14 K, ≤10−9 torr) with high-energy UV photons provided by a synchrotron source in three different ranges: the 0th order light (4.1–49.6 eV, 25–300 nm), the He i line (21.2 eV, 58.4 nm), and the He ii line (40.8 eV, 30.4 nm). The photodestruction of pyrimidine was monitored with IR spectroscopy, and the samples recovered at room temperature were analyzed with liquid and gas chromatographies. Uracil and its precursor 4(3H)-pyrimidone were found in all samples, with absolute and relative abundances varying significantly from one sample to another. These results support a scenario in which compounds of biological interest can be formed and survive in environments subjected to high-energy UV radiation fields. Key Words: Pyrimidine—Nucleobases—Interstellar ices—Cometary ices—High-energy photons—Molecular processes—Prebiotic chemistry. Astrobiology 14, 119–131.
- Published
- 2014
20. The Calculated Infrared Spectra of Functionalized Hexamethylenetetramine (HMT) Molecules
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Timothy J. Lee, Partha P. Bera, Scott A. Sandford, and Michel Nuevo
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Physics ,chemistry.chemical_compound ,Astrochemistry ,chemistry ,Space and Planetary Science ,Physical chemistry ,Infrared spectroscopy ,Molecule ,Astronomy and Astrophysics ,Hexamethylenetetramine - Published
- 2019
21. Thymine and Other Prebiotic Molecules Produced from the Ultraviolet Photo-Irradiation of Pyrimidine in Simple Astrophysical Ice Analogs
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Scott A. Sandford, Michel Nuevo, Christopher K. Materese, Partha P. Bera, and Timothy J. Lee
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Purine ,Extraterrestrial Environment ,Pyrimidine ,Ultraviolet Rays ,Guanine ,Methanol ,Ice ,Water ,Uracil ,Pyrimidine dimer ,Reference Standards ,Photochemistry ,Agricultural and Biological Sciences (miscellaneous) ,Gas Chromatography-Mass Spectrometry ,Thymine ,Nucleobase ,chemistry.chemical_compound ,Pyrimidines ,chemistry ,Space and Planetary Science ,Methane ,Chromatography, High Pressure Liquid ,Cytosine - Abstract
The informational subunits of RNA or DNA consist of substituted N-heterocyclic compounds that fall into two groups: those based on purine (C₅H₄N₄) (adenine and guanine) and those based on pyrimidine (C₄H₄N₂) (uracil, cytosine, and thymine). Although not yet detected in the interstellar medium, N-heterocycles, including the nucleobase uracil, have been reported in carbonaceous chondrites. Recent laboratory experiments and ab initio calculations have shown that the irradiation of pyrimidine in ices containing H₂O, NH₃, or both leads to the abiotic production of substituted pyrimidines, including the nucleobases uracil and cytosine. In this work, we studied the methylation and oxidation of pyrimidine in CH₃OH:pyrimidine, H₂O:CH₃OH:pyrimidine, CH₄:pyrimidine, and H₂O:CH₄:pyrimidine ices irradiated with UV photons under astrophysically relevant conditions. The nucleobase thymine was detected in the residues from some of the mixtures. Our results suggest that the abundance of abiotic thymine produced by ice photolysis and delivered to the early Earth may have been significantly lower than that of uracil. Insofar as the delivery of extraterrestrial molecules was important for early biological chemistry on early Earth, these results suggest that there was more uracil than thymine available for emergent life, a scenario consistent with the RNA world hypothesis.
- Published
- 2013
22. Isotopic and chemical variation of organic nanoglobules in primitive meteorites
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Larry R. Nittler, Stefanie N. Milam, A. L. David Kilcoyne, Rhonda M. Stroud, Bradley T. De Gregorio, Michel Nuevo, Conel M. O'd. Alexander, Nabil Bassim, Scott A. Sandford, George D. Cody, and Thomas J. Zega
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chemistry.chemical_classification ,Geophysics ,chemistry ,Meteorite ,Space and Planetary Science ,Chondrite ,Environmental chemistry ,digestive, oral, and skin physiology ,Organic matter ,Compositional variation ,Isotopic composition ,Astrobiology - Abstract
Organic nanoglobules are microscopic spherical carbon-rich objects present in chondritic meteorites and other astromaterials. We performed a survey of the morphology, organic functional chemistry, and isotopic composition of 184 nanoglobules in insoluble organic matter (IOM) residues from seven primitive carbonaceous chondrites. Hollow and solid nanoglobules occur in each IOM residue, as well as globules with unusual shapes and structures. Most nanoglobules have an organic functional chemistry similar to, but slightly more carboxyl-rich than, the surrounding IOM, while a subset of nanoglobules have a distinct, highly aromatic functionality. The range of nanoglobule N isotopic compositions was similar to that of nonglobular 15N-rich hotspots in each IOM residue, but nanoglobules account for only about one third of the total 15N-rich hotspots in each sample. Furthermore, many nanoglobules in each residue contained no 15N enrichment above that of bulk IOM. No morphological indicators were found to robustly distinguish the highly aromatic nanoglobules from those that have a more IOM-like functional chemistry, or to distinguish 15N-rich nanoglobules from those that are isotopically normal. The relative abundance of aromatic nanoglobules was lower, and nanoglobule diameters were greater, in more altered meteorites, suggesting the creation/modification of IOM-like nanoglobules during parent-body processing. However, 15N-rich nanoglobules, including many with highly aromatic functional chemistry, likely reflect preaccretionary isotopic fractionation in cold molecular cloud or protostellar environments. These data indicate that no single formation mechanism can explain all of the observed characteristics of nanoglobules, and their properties are likely a result of multiple processes occurring in a variety of environments.
- Published
- 2013
23. Mechanisms for the Formation of Thymine Under Astrophysical Conditions and Implications for the Origin of Life
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Christopher K. Materese, Timothy J. Lee, Scott A. Sandford, Partha P. Bera, and Michel Nuevo
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Evolution, Chemical ,010504 meteorology & atmospheric sciences ,Pyrimidine ,Stereochemistry ,Origin of Life ,General Physics and Astronomy ,Uracil ,Photochemistry ,01 natural sciences ,Article ,Thymine ,Nucleobase ,chemistry.chemical_compound ,chemistry ,Abiogenesis ,0103 physical sciences ,Molecule ,Quantum Theory ,Physical and Theoretical Chemistry ,010303 astronomy & astrophysics ,Cytosine ,DNA ,0105 earth and related environmental sciences - Abstract
Nucleobases are the carriers of the genetic information in ribonucleic acid and deoxyribonucleic acid (DNA) for all life on Earth. Their presence in meteorites clearly indicates that compounds of biological importance can form via non-biological processes in extraterrestrial environments. Recent experimental studies have shown that the pyrimidine-based nucleobases uracil and cytosine can be easily formed from the ultraviolet irradiation of pyrimidine in H2O-rich ice mixtures that simulate astrophysical processes. In contrast, thymine, which is found only in DNA, is more difficult to form under the same experimental conditions, as its formation usually requires a higher photon dose. Earlier quantum chemical studies confirmed that the reaction pathways were favorable provided that several H2O molecules surrounded the reactants. However, the present quantum chemical study shows that the formation of thymine is limited because of the inefficiency of the methylation of pyrimidine and its oxidized derivatives in an H2O ice, as supported by the laboratory studies. Our results constrain the formation of thymine in astrophysical environments and thus the inventory of organic molecules delivered to the early Earth and have implications for the role of thymine and DNA in the origin of life.
- Published
- 2016
24. XANES analysis of organic residues produced from the UV irradiation of astrophysical ice analogs
- Author
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Scott A. Sandford, Michel Nuevo, Stefanie N. Milam, George D. Cody, A. L. D. Kilcoyne, and B. T. De Gregorio
- Subjects
Atmospheric Science ,X-ray spectroscopy ,Infrared ,Chemistry ,Inorganic chemistry ,Aerospace Engineering ,Extraterrestrial materials ,Astronomy and Astrophysics ,medicine.disease_cause ,Mass spectrometry ,XANES ,Geophysics ,Space and Planetary Science ,medicine ,General Earth and Planetary Sciences ,Spectroscopy ,Chemical composition ,Ultraviolet - Abstract
Organic residues formed in the laboratory from the ultraviolet (UV) photo-irradiation or ion bombardment of astrophysical ice analogs have been extensively studied for the last 15 years with a broad suite of techniques, including infrared (IR) and UV spectroscopies, as well as mass spectrometry. Analyses of these materials show that they consist of complex mixtures of organic compounds stable at room temperature, mostly soluble, that have not been fully characterized. However, the hydrolysis products of these residues have been partly identified using chromatography techniques, which indicate that they contain molecular precursors of prebiotic interest such as amino acids, nitrile-bearing compounds, and amphiphilic compounds. In this study, we present the first X-ray absorption near-edge structure (XANES) spectroscopy measurements of three organic residues made from the UV irradiation of ices having different starting compositions. XANES spectra confirm the presence of different chemical functions in these residues, and indicate that they are rich in nitrogenand oxygen-bearing species. These data can be compared with XANES measurements of extraterrestrial materials. Finally, this study also shows how soft X rays can alter the chemical composition of samples.
- Published
- 2011
25. Photo-desorbed species produced by the UV/EUV irradiation of an H2O:CO2:NH3 ice mixture
- Author
-
Y.-G. Fan, Michel Nuevo, H.-S. Fung, T. S. Yih, C.-Y. R. Wu, Y.-J. Chen, C. C. Chu, and W-H. Ip
- Subjects
Atmospheric Science ,Solar System ,Materials science ,Photodissociation ,Analytical chemistry ,Aerospace Engineering ,Astronomy and Astrophysics ,Substrate (electronics) ,Mass spectrometry ,medicine.disease_cause ,Geophysics ,Space and Planetary Science ,Desorption ,Extreme ultraviolet ,medicine ,General Earth and Planetary Sciences ,Irradiation ,Atomic physics ,Ultraviolet - Abstract
An H2O:CO2:NH3 = 1:1:1 ice mixture, used as a model mixture for cometary and interstellar ices, was irradiated with ultraviolet (UV)/extreme ultraviolet (EUV) photons in the broad 4–20 eV (62–310 nm) energy range at 16 K. The desorbed species were detected in situ by mass spectrometry during photo-irradiation, and a quartz microbalance was used as a substrate to measure the mass of material remaining on the surface. The total mass desorption for this H2O:CO2:NH3 = 1:1:1 ice mixture at 16 K was measured to be 1.8 × 10−18 μg photon−1, which is comparable to the 1.5 × 10−18 μg photon−1 measured for pure H2O ice irradiated under the same conditions. The main desorbed species produced during the photolysis of the ices were H2, NH 2 • , OH•, CO, and O2, along with the starting components H2O, NH3, and CO2. We also tentatively assigned minor mass peaks to larger species such as OCN•/OCN−, HNCO, CH4, H2CO, CH3OH, and HCOOH. This result supports the scenario in which complex organic molecules can be formed in cometary and/or astrophysical ices and desorbed to the gas phase, and helps to better understand the photochemical processes occurring at the surface of Solar System icy bodies such as comets, as well as in cold astrophysical environments such as star-forming regions and protostars.
- Published
- 2011
26. The mid-infrared transmission spectra of multiple stones from the Almahata Sitta meteorite
- Author
-
Michel Nuevo, Stefanie N. Milam, Peter Jenniskens, Muawia H. Shaddad, and Scott A. Sandford
- Subjects
Olivine ,Chemistry ,Infrared spectroscopy ,Mineralogy ,Pyroxene ,Ureilite ,engineering.material ,Silicate ,Strewn field ,chemistry.chemical_compound ,Geophysics ,Meteorite ,Space and Planetary Science ,engineering ,Absorption (electromagnetic radiation) - Abstract
450 cm )1 ; 2.5–22.2 lm) transmission spectra taken from 26 different stones collected from the strewn field. The ureilite spectra show a number of absorption bands including a complex feature centered near 1000 cm )1 (10 lm) due to Si-O stretching vibrations. The profiles of the silicate features fall along a mixing line with endmembers represented by Mgrich olivines and pyroxenes, and no evidence is seen for the presence of phyllosilicates. The relative abundances of olivine and pyroxene show substantial variation from sample to sample and sometimes differ between multiple samples taken from the same stone. Analysis of a mass normalized coaddition of all our ureilite spectra yields an olivine-to-pyroxene ratio of 74:26, a value that falls in the middle of the range inferred from the infrared spectra of other ureilites. Both the predominance of olivine and the variable olivine-to-pyroxene ratio are consistent with the known composition and heterogeneity of other ureilites. Variations in the colors of the samples and the intensities of the silicate feature relative to the mass of the samples indicate a significant contribution from additional materials having no strong absorption bands, most likely graphitized carbon, diamonds, and ⁄ or metals.
- Published
- 2010
27. The Photochemistry of Purine in Ice Analogs Relevant to Dense Interstellar Clouds
- Author
-
Brittiana L. McDowell, Michel Nuevo, Christina E. Buffo, Scott A. Sandford, and Christopher K. Materese
- Subjects
Physics ,Purine ,010504 meteorology & atmospheric sciences ,Pyrimidine ,Guanine ,Astronomy and Astrophysics ,Uracil ,Photochemistry ,01 natural sciences ,Thymine ,Nucleobase ,chemistry.chemical_compound ,chemistry ,Space and Planetary Science ,0103 physical sciences ,010303 astronomy & astrophysics ,Cytosine ,DNA ,0105 earth and related environmental sciences - Abstract
The aromatic nitrogen heterocyclic compound purine is the core structural framework of many important biomolecules, particularly nucleobases. Purine and purine derivatives have been observed in carbonaceous chondrites, and it has been hypothesized that the exogenous delivery of these compounds, along with many other biologically relevant compounds, may have played a role in the emergence of life. Numerous experiments in our laboratory have demonstrated that the nucleobases used by life to encode genetic material could have been produced abiotically under astrophysically relevant conditions. Specifically, the UV photoprocessing of pyrimidine and purine in simple ices of astrophysical interest has resulted in the production of all five biological nucleobases, namely, uracil (RNA), cytosine (RNA and DNA), thymine (DNA), adenine (RNA and DNA), and guanine (RNA and DNA). Additionally, follow-up work has examined the photochemistry of pyrimidine in more complex astrophysical ice mixtures to better understand the formation of these compounds under realistic conditions. In this work, we examine the photochemistry of purine in more complex ices of astrophysical interest and compare our results with those from simpler ice mixtures. We also examine the effects of competing parallel synthesis of organic compounds in the ices (unrelated to purine). Finally, we discuss the astrophysical and astrobiological implications of our findings.
- Published
- 2018
28. Urea, Glycolic Acid, and Glycerol in an Organic Residue Produced by Ultraviolet Irradiation of Interstellar/Pre-Cometary Ice Analogs
- Author
-
Michel Nuevo, Uwe J. Meierhenrich, Wolfram Thiemann, Louis Le Sergeant d'Hendecourt, and Jan Hendrik Bredehöft
- Subjects
Glycerol ,Solar System ,Astrochemistry ,Earth, Planet ,Ultraviolet Rays ,Origin of Life ,Inorganic chemistry ,Chemical reaction ,Gas Chromatography-Mass Spectrometry ,Residue (chemistry) ,chemistry.chemical_compound ,Abiogenesis ,Acetamides ,Exobiology ,Urea ,Glycolic acid ,Chemistry ,Ice ,Temperature ,Meteoroids ,Amides ,Agricultural and Biological Sciences (miscellaneous) ,Glycolates ,Interstellar medium ,Models, Chemical ,Meteorite ,Space and Planetary Science ,Acids - Abstract
More than 50 stable organic molecules have been detected in the interstellar medium (ISM), from ground-based and onboard-satellite astronomical observations, in the gas and solid phases. Some of these organics may be prebiotic compounds that were delivered to early Earth by comets and meteorites and may have triggered the first chemical reactions involved in the origin of life. Ultraviolet irradiation of ices simulating photoprocesses of cold solid matter in astrophysical environments have shown that photochemistry can lead to the formation of amino acids and related compounds. In this work, we experimentally searched for other organic molecules of prebiotic interest, namely, oxidized acid labile compounds. In a setup that simulates conditions relevant to the ISM and Solar System icy bodies such as comets, a condensed CH(3)OH:NH(3) = 1:1 ice mixture was UV irradiated at approximately 80 K. The molecular constituents of the nonvolatile organic residue that remained at room temperature were separated by capillary gas chromatography and identified by mass spectrometry. Urea, glycolic acid, and glycerol were detected in this residue, as well as hydroxyacetamide, glycerolic acid, and glycerol amide. These organics are interesting target molecules to be searched for in space. Finally, tentative mechanisms of formation for these compounds under interstellar/pre-cometary conditions are proposed.
- Published
- 2010
29. Formation of Uracil from the Ultraviolet Photo-Irradiation of Pyrimidine in Pure H2O Ices
- Author
-
Scott A. Sandford, Michel Nuevo, Jason P. Dworkin, Jamie E. Elsila, and Stefanie N. Milam
- Subjects
Murchison meteorite ,Extraterrestrial Environment ,Spectrophotometry, Infrared ,Pyrimidine ,Ultraviolet Rays ,Photochemistry ,medicine.disease_cause ,Gas Chromatography-Mass Spectrometry ,Nucleobase ,chemistry.chemical_compound ,Abiogenesis ,Chondrite ,medicine ,Uracil ,Chromatography, High Pressure Liquid ,Chemistry ,Ice ,Water ,Agricultural and Biological Sciences (miscellaneous) ,Interstellar medium ,Purines ,Space and Planetary Science ,Spectrophotometry, Ultraviolet ,Ultraviolet ,Half-Life - Abstract
The detection of nucleobases in carbonaceous chondrites such as Murchison supports the scenario in which extraterrestrial organic molecules could have contributed to the origin of life on Earth. However, such large molecules have not been observed to date in astrophysical environments, in particular, comets and the interstellar medium (ISM). The physico-chemical conditions under which nucleobases and, more generally, N-heterocycles were formed are unknown, as are their mechanisms of formation. In this work, H2O:pyrimidine ice mixtures were irradiated with UV photons under interstellar/cometary-relevant conditions to study the formation of pyrimidine derivatives, including the nucleobase uracil. Liquid and gas chromatography analyses of the samples produced in our experiments revealed the presence of numerous photoproducts among which 4(3H)-pyrimidone and uracil could be conclusively identified. The photostability of pyrimidine against UV photons was also studied, and we showed that it would survive from the ISM to the solar nebula if formed and preserved in ice mantles on the surface of cold grains. We propose pathways for the formation of 4(3H)-pyrimidone and uracil under astrophysically relevant conditions and discuss the possibility for such molecules to survive from the ISM to their delivery to Earth and other Solar System bodies.
- Published
- 2009
30. Amino acids produced from the ultraviolet/extreme-ultraviolet irradiation of naphthalene in a H2O+NH3 ice mixture
- Author
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C.-Y. Cheng, Wing-Huen Ip, Michel Nuevo, H.-R. Tsai, Y.-J. Chen, H.-S. Fung, T. S. Yih, and C.-Y. R. Wu
- Subjects
chemistry.chemical_classification ,Physics ,Astrochemistry ,Photodissociation ,Polycyclic aromatic hydrocarbon ,Astronomy and Astrophysics ,Photochemistry ,medicine.disease_cause ,Amino acid ,Residue (chemistry) ,chemistry.chemical_compound ,chemistry ,Space and Planetary Science ,Extreme ultraviolet ,medicine ,Ultraviolet ,Naphthalene - Abstract
In this work, we show that the irradiation of naphthalene (C 10 H 8 ), the smallest polycyclic aromatic hydrocarbon (PAH), mixed in a H 2 O+NH 3 ice mixture with 4-20 eV (62-310 nm, i.e. in the ultraviolet/extreme-ultraviolet ranges) photons at 15 K leads to the formation of an organic residue where many amino acids were identified. However, the distribution of these amino acids is different from what was reported in previous laboratory experiments where ice mixtures containing other sources of carbon (CO, CO 2 , CH 4 and CH 3 OH) were irradiated with ultraviolet photons, indicating that amino acids can be formed via several mechanisms. This result also implies that naphthalene, and probably other PAHs, constitute a non-negligible source of interstellar carbon likely to form organic molecules after photolysis, supporting a scenario where molecules of biological interest could be formed in many different astrophysical environments before being delivered to the early Earth by meteorites.
- Published
- 2008
31. Amino acids formed from the UV/EUV irradiation of inorganic ices of astrophysical interest
- Author
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Y.-J. Chen, T. S. Yih, H.-S. Fung, H.-R. Tsai, Michel Nuevo, Wing-Huen Ip, C.-Y. Cheng, and C.-Y. R. Wu
- Subjects
chemistry.chemical_classification ,Atmospheric Science ,Chemistry ,Inorganic chemistry ,Aerospace Engineering ,Astronomy and Astrophysics ,medicine.disease_cause ,High-performance liquid chromatography ,Organic compound ,Methane ,Amino acid ,chemistry.chemical_compound ,Geophysics ,Space and Planetary Science ,Extreme ultraviolet ,medicine ,General Earth and Planetary Sciences ,Methanol ,Irradiation ,Ultraviolet - Abstract
An experiment where a H 2 O:CO 2 :NH 3 = 1:1:1 ice mixture was irradiated using the ultraviolet/extreme ultraviolet (UV/EUV) light provided by a synchrotron beam in the broad 4–20 eV (62–310 nm) range at 16 K is presented here. The main originalities of the present work are the composition of the starting ice mixture, since it did not contain any organic compound, in particular no methanol (CH 3 OH) nor methane (CH 4 ) as for previous similar experiments, and the photon energy range. Several amino acids were produced: nine were identified of which seven could be quantified, and some others tentatively identified using high-performance liquid chromatography (HPLC). This result shows that it is possible to form complex organics such as amino acids from the irradiation of ice mixtures containing C-, H-, O- and N-atom bearing compounds, whatever the organic/inorganic nature of these compounds. Only the distribution of the formed amino acids is different from previous experiments. This discrepancy may be due to the starting mixture composition and/or the different energy range used for the irradiation. These two parameters are discussed in regard of their implications for the formation of amino acids in the laboratory and in astrophysical environments.
- Published
- 2007
32. Enantiomeric separation of complex organic molecules produced from irradiation of interstellar/circumstellar ice analogs
- Author
-
Louis Le Sergeant d'Hendecourt, Michel Nuevo, Uwe J. Meierhenrich, G. M. Muñoz Caro, Emmanuel Dartois, D. Deboffle, Laurent Nahon, Wolfram Thiemann, and Jan Hendrik Bredehöft
- Subjects
Murchison meteorite ,chemistry.chemical_classification ,Atmospheric Science ,Astrochemistry ,Chemistry ,Aerospace Engineering ,Astronomy and Astrophysics ,medicine.disease_cause ,Mass spectrometry ,Photochemistry ,Amino acid ,Residue (chemistry) ,Geophysics ,Space and Planetary Science ,medicine ,General Earth and Planetary Sciences ,Homochirality ,Enantiomer ,Ultraviolet - Abstract
Irradiation of interstellar/circumstellar ice analogs by ultraviolet (UV) light followed by warm up in the laboratory leads to the formation of complex organic molecules, stable at room temperature. Hydrolysis of the room temperature residue releases amino acids, the building blocks of proteins. These amino acids exist in two different forms ( l and d ), but proteins encountered in living beings consist exclusively of l enantiomers. The origin of this property, called homochirality, is still unknown. Amino acids can be detected and quantified by chemical techniques such as chiral gas chromatography coupled with mass spectrometry (GC-MS). Enantiomers of chiral organics are also known to interact selectively with circularly polarized light (CPL), leading to a selective production or destruction of the final compounds. This paper describes how we settled an experiment where amino acids are formed by irradiation of interstellar/circumstellar ice analogs with ultraviolet (UV) CPL, produced by a synchrotron radiation beamline, which allowed us to quantify the effect of such polarized light on the production of amino acids. These results can be compared to the enantiomeric excesses measured in primitive meteorites such as Murchison.
- Published
- 2007
33. Carbamic acid produced by the UV/EUV irradiation of interstellar ice analogs
- Author
-
Y. Y. Lee, J.-M. Hsieh, W-H. Ip, Michel Nuevo, C.-Y. R. Wu, S.-Y. Chiang, Y.-J. Chen, J.-M. Chen, H.-S. Fung, T. S. Yih, and Wei-Hsin Sun
- Subjects
Physics ,Astrochemistry ,Infrared ,Interstellar ice ,Infrared spectroscopy ,Astronomy and Astrophysics ,Context (language use) ,Astrophysics ,medicine.disease_cause ,chemistry.chemical_compound ,Carbamic acid ,chemistry ,Space and Planetary Science ,medicine ,Spectroscopy ,Ultraviolet - Abstract
Context. Carbamic acid (NH 2 COOH) is the smallest amino acid, smaller than the smallest proteinaceous amino acid glycine. This compound has never been observed in the interstellar medium (ISM). Previous experiments where ice mixtures containing H 2 O, CO 2 and NH 3 were subjected to 1-MeV proton bombardment showed that carbamic acid is formed in a stable zwitterionic (NH(COO - ) form. Aims. In the present work, we have carried out irradiations of ice mixtures containing H 2 O, 12 CO 2 / 13 CO 2 and NH 3 with ultraviolet (UV)/extreme ultraviolet (EUV) photons provided by a synchrotron source in the 4-20 eV range, and compared the results with those obtained for energetic protons. Methods. Infrared (IR) spectroscopy and mass spectrometry were used to identify the formed photo-products and monitor their evolution in the ices at 15 K and during the warming up to room temperature in the formed residues. Results. We identified the IR absorption features of HNCO, OCN - , CO, NH+ 4 and NH 2 CHO at low temperature in the ices, and features assigned to carbamic acid in the residues around 250 K. Finally, we conclude that under our experimental conditions, unlike what was obtained after bombardment with energetic protons, carbamic acid may be formed in the neutral form, and propose some photochemical pathways leading to its formation.
- Published
- 2006
34. Nature and evolution of the dominant carbonaceous matter in interplanetary dust particles: effects of irradiation and identification with a type of amorphous carbon
- Author
-
Michel Nuevo, D. Deboffle, Nicolas Chauvin, D. Le Du, Graciela Matrajt, C. Boukari, Gilles Montagnac, G. M. Muñoz Caro, Louis D'Hendecourt, Emmanuel Dartois, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de Sciences de la Terre (LST), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
infrared: solar system ,Infrared ,Infrared spectroscopy ,Astrophysics ,010502 geochemistry & geophysics ,medicine.disease_cause ,01 natural sciences ,methods: laboratory ,[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO] ,symbols.namesake ,Interplanetary dust cloud ,0103 physical sciences ,medicine ,Irradiation ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Computer Science::Cryptography and Security ,0105 earth and related environmental sciences ,infrared: ISM ,Physics ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,Astronomy and Astrophysics ,Interstellar medium ,molecular processes ,Amorphous carbon ,13. Climate action ,Space and Planetary Science ,symbols ,Astrophysics::Earth and Planetary Astrophysics ,Raman spectroscopy ,Ultraviolet - Abstract
Aims. Interplanetary dust particle (IDP) matter probably evolved under irradiation in the interstellar medium (ISM) and the solar nebula. Currently IDPs are exposed to irradiation in the Solar System. Here the effects of UV and proton processing on IDP matter are studied experimentally. The structure and chemical composition of the bulk of carbon matter in IDPs is characterized. Methods. Several IDPs were further irradiated in the laboratory using ultraviolet (UV) photons and protons in order to study the effects of such processing. By means of infrared and Raman spectroscopy, IDPs were also compared to different materials that serve as analogs of carbon grains in the dense and diffuse ISM. Results. The carbonaceous fraction of IDPs is dehydrogenated by exposure to hard UV photons or 1 MeV protons. On the other hand, proton irradiation at lower energies (20 keV) leads to an efficient hydrogenation of the carbonaceous IDP matter. The dominant type of carbon in IDPs, observed with Raman and infrared spectroscopy, is found to be either a form of amorphous carbon (a-C) or hydrogenated amorphous carbon (a-C:H), depending on the IDP, consisting of aromatic units with an average domain size of 1.35 nm (5-6 rings in diameter), linked by aliphatic chains. Conclusions. The D- and 15 N-enrichments associated to an aliphatic component in some IDPs are probably the result of chemical reactions at cold temperatures. It is proposed that the amorphous carbon in IDPs was formed by energetic processing (UV photons and cosmic rays) of icy grains, maybe during the dense cloud stage, and more likely on the surface of the disk during the T Tauri phase of our Sun. This would explain the isotopic anomalies and morphology of IDPs. Partial annealing, 300-400 °C, is required to convert an organic residue from ice photoprocessing into the amorphous carbon with low heteroatom content found in IDPs. Such annealing might have occurred as the particles approached the Sun and/or during atmospheric entry heating.
- Published
- 2006
35. Photosynthesis and Photo-Stability of Nucleic Acids in Prebiotic Extraterrestrial Environments
- Author
-
Timothy J. Lee, Scott A. Sandford, Christopher K. Materese, Michel Nuevo, and Partha P. Bera
- Subjects
Extraterrestrial Environment ,Pyrimidine ,Ultraviolet Rays ,Stereochemistry ,Article ,Nucleobase ,Cytosine ,chemistry.chemical_compound ,Computational chemistry ,Nucleic Acids ,Radiation, Ionizing ,Photosynthesis ,Uracil ,Photons ,Ice ,Absorption, Radiation ,RNA ,Models, Theoretical ,Thymine ,Prebiotics ,chemistry ,Nucleic acid ,DNA - Abstract
Laboratory experiments have shown that the UV photo-irradiation of low-temperature ices of astrophysical interest leads to the formation of organic molecules, including molecules important for biology such as amino acids, quinones, and amphiphiles. When pyrimidine is introduced into these ices, the products of irradiation include the nucleobases uracil, cytosine, and thymine, the informational sub-units of DNA and RNA, as well as some of their isomers. The formation of these compounds, which has been studied both experimentally and theoretically, requires a succession of additions of OH, NH2, and CH3 groups to pyrimidine. Results show that H2O ice plays key roles in the formation of the nucleobases, as an oxidant, as a matrix in which reactions can take place, and as a catalyst that assists proton abstraction from intermediate compounds. As H2O is also the most abundant icy component in most cold astrophysical environments, it probably plays the same roles in space in the formation of biologically relevant compounds. Results also show that although the formation of uracil and cytosine from pyrimidine in ices is fairly straightforward, the formation of thymine is not. This is mostly due to the fact that methylation is a limiting step for its formation, particularly in H2O-rich ices, where methylation must compete with oxidation. The relative inefficiency of the abiotic formation of thymine to that of uracil and cytosine, together with the fact that thymine has not been detected in meteorites, are not inconsistent with the RNA world hypothesis. Indeed, a lack of abiotically produced thymine delivered to the early Earth may have forced the choice for an RNA world, in which only uracil and cytosine are needed, but not thymine.
- Published
- 2014
36. Radar-enabled recovery of the Sutter's Mill meteorite, a carbonaceous chondrite regolith breccia
- Author
-
Matthias Laubenstein, Jon M. Friedrich, Akane Yamakawa, Kunihiko Nishiizumi, Kenji Hagiya, Doug Klotz, A. B. Verchovsky, Jason P. Dworkin, Peter Jenniskens, Peter Brown, Andrew M. Davis, I. E. Kohl, Ryan C. Ogliore, Yasunori Hamajima, Derek W. G. Sears, Ryuji Okazaki, Michel Nuevo, Marc Fries, Mark H. Thiemens, Igor S. Puchtel, Philipp R. Heck, Mourad Harir, Jonathan A. Lawton, Daniel P. Glavin, Takahiro Hiroi, Zelimir Gabelica, Steven B. Simon, Sarah M. Roeske, Jeffrey A. Fries, Beverly Girten, Kazumasa Ohsumi, Michael Lerche, Simon P. Worden, David Barnes, Takashi Mikouchi, Kazuhide Nagashima, Robert Beauford, Thomas A. Cahill, M. Nunn, Marc W. Caffee, Jim Albers, Josh Wimpenny, Richard J. Walker, Sandra Pizzarello, Kenneth D. Smith, G. R. Eppich, Alexander N. Krot, Jérôme Gattacceca, Norbert Hertkorn, Scott A. Sandford, Mike Hankey, Kees C. Welten, Qing-Zhu Yin, Phillipe Schmitt-Kopplin, Hiroyuki Takechi, Pierre Rochette, George Cooper, Andrew Steele, Monica E. Erdman, Robert Matson, Denton S. Ebel, Aaron S. Burton, Cin-Ty A. Lee, Monica M. Grady, Jamie E. Elsila, Elizabeth A. Silber, Edward D. Young, Kenneth L. Verosub, Michael E. Zolensky, and Keisuke Nagao
- Subjects
Multidisciplinary ,Allende meteorite ,Meteorite ,Asteroid ,Chondrite ,Carbonaceous chondrite ,Breccia ,Regolith ,Geology ,Parent body ,Astrobiology - Abstract
The Meteor That Fell to Earth In April 2012, a meteor was witnessed over the Sierra Nevada Mountains in California. Jenniskens et al. (p. 1583 ) used a combination of photographic and video images of the fireball coupled with Doppler weather radar images to facilitate the rapid recovery of meteorite fragments. A comprehensive analysis of some of these fragments shows that the Sutter's Mill meteorite represents a new type of carbonaceous chondrite, a rare and primitive class of meteorites that contain clues to the origin and evolution of primitive materials in the solar system. The unexpected and complex nature of the fragments suggests that the surfaces of C-class asteroids, the presumed parent bodies of carbonaceous chondrites, are more complex than previously assumed.
- Published
- 2012
37. Laboratory Astrochemistry: A Powerful Tool to Understand the Origin of Organic Molecules in the Interstellar Medium, Comets, and Meteorites
- Author
-
Michel Nuevo
- Subjects
Interstellar medium ,Astrochemistry ,Meteorite ,Chemistry ,Astrobiology ,Organic molecules - Published
- 2012
38. Nucleobases and prebiotic molecules in organic residues produced from the ultraviolet photo-irradiation of pyrimidine in NH(3) and H(2)O+NH(3) ices
- Author
-
Scott A. Sandford, Stefanie N. Milam, and Michel Nuevo
- Subjects
Pyrimidine ,Extraterrestrial Environment ,Ultraviolet Rays ,Water ,Uracil ,DNA ,Meteoroids ,Photochemistry ,Agricultural and Biological Sciences (miscellaneous) ,Nucleobase ,chemistry.chemical_compound ,Pyrimidines ,chemistry ,Space and Planetary Science ,Chondrite ,Nucleic acid ,Organic chemistry ,Molecule ,RNA ,Cytosine - Abstract
Although not yet identified in the interstellar medium (ISM), N-heterocycles including nucleobases-the information subunits of DNA and RNA-are present in carbonaceous chondrites, which indicates that molecules of biological interest can be formed in non-terrestrial environments via abiotic pathways. Recent laboratory experiments and ab initio calculations have already shown that the irradiation of pyrimidine in pure H(2)O ices leads to the formation of a suite of oxidized pyrimidine derivatives, including the nucleobase uracil. In the present work, NH(3):pyrimidine and H(2)O:NH(3):pyrimidine ice mixtures with different relative proportions were irradiated with UV photons under astrophysically relevant conditions. Liquid- and gas-chromatography analysis of the resulting organic residues has led to the detection of the nucleobases uracil and cytosine, as well as other species of prebiotic interest such as urea and small amino acids. The presence of these molecules in organic residues formed under abiotic conditions supports scenarios in which extraterrestrial organics that formed in space and were subsequently delivered to telluric planets via comets and meteorites could have contributed to the inventory of molecules that triggered the first biological reactions on their surfaces.
- Published
- 2012
39. NON-RACEMIC AMINO ACID PRODUCTION BY ULTRAVIOLET IRRADIATION OF ACHIRAL INTERSTELLAR ICE ANALOGS WITH CIRCULARLY POLARIZED LIGHT
- Author
-
Uwe J. Meierhenrich, Cornelia Meinert, Pierre de Marcellus, Laurent Nahon, Jean-Jacques Filippi, Louis D'Hendecourt, Michel Nuevo, Grégoire Danger, D. Deboffle, Aix Marseille Université (AMU), Institut de Chimie de Nice (ICN), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Hépato-Gastroentérologie, Centre Hospitalier Universitaire de Nice (CHU Nice), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), and Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)
- Subjects
Physics ,Solar System ,Nebula ,Astrochemistry ,Star formation ,Infrared ,Interstellar ice ,Astronomy and Astrophysics ,Astrophysics ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Astrobiology ,Meteorite ,13. Climate action ,Space and Planetary Science ,[SDU]Sciences of the Universe [physics] ,0103 physical sciences ,Ultraviolet light ,[CHIM]Chemical Sciences ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS - Abstract
WOS:000286196200027; International audience; The delivery of organic matter to the primitive Earth via comets and meteorites has long been hypothesized to be an important source for prebiotic compounds such as amino acids or their chemical precursors that contributed to the development of prebiotic chemistry leading, on Earth, to the emergence of life. Photochemistry of inter/circumstellar ices around protostellar objects is a potential process leading to complex organic species, although difficult to establish from limited infrared observations only. Here we report the first abiotic cosmic ice simulation experiments that produce species with enantiomeric excesses (e.e.'s). Circularly polarized ultraviolet light (UV-CPL) from a synchrotron source induces asymmetric photochemistry on initially achiral inter/circumstellar ice analogs. Enantioselective multidimensional gas chromatography measurements show significant e.e.'s of up to 1.34% for (C-13)-alanine, for which the signs and absolute values are related to the helicity and number of CPL photons per deposited molecule. This result, directly comparable with some L excesses measured in meteorites, supports a scenario in which exogenous delivery of organics displaying a slight L excess, produced in an extraterrestrial environment by an asymmetric astrophysical process, is at the origin of biomolecular asymmetry on Earth. As a consequence, a fraction of the meteoritic organic material consisting of non-racemic compounds may well have been formed outside the solar system. Finally, following this hypothesis, we support the idea that the protosolar nebula has indeed been formed in a region of massive star formation, regions where UV-CPL of the same helicity is actually observed over large spatial areas.
- Published
- 2011
40. The impact and recovery of asteroid 2008 TC3
- Author
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Janice L. Bishop, D. Rumble, Peter Brown, R. E. Spalding, E. Tagliaferri, J. Kuiper, Henry H. Hsieh, Ayman M. Kudoda, M. Kozubal, Alan Fitzsimmons, Jiri Borovicka, Andrew Steele, Michael E. Zolensky, Jon M. Friedrich, Petr Pravec, Scott A. Sandford, L. Le, Simon P. Worden, G. A. Robinson, Jeremie Vaubaillon, D. Numan, Mark Boslough, S. Elsir, Muawia H. Shaddad, Samuel R. Duddy, Stefanie N. Milam, Wayne N. Edwards, Z. Charvat, Steve Chesley, Ron Dantowitz, Michel Nuevo, G. Ramsay, Jim Albers, Peter Jenniskens, Rocco L. Mancinelli, Carl Sagan Center, SETI Institute, Department of Physics and Astronomy, University of Khartoum, Physics Department, Juba University, NASA Johnson Space Center, Mail Code KT, Houston, Department of Chemistry, Fordham University, Geophysical Laboratory, Carnegie Institution of Washington, Jet Propulsion Laboratory, California Institute of Technology (JPL), School of Mathematics and Physics, Queen's University, Armagh Observatory, College Hill, Department of Physics and Astronomy, University of Western Ontario, ET Space Systems, Sandia National Laboratories, Clay Center Observatory, Dexter and Southfield Schools, Astronomical Institute, Academy of Sciences, Czech Hydrometeorological Institute, Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Groupe Astrométrie et Planétologie (GAP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Dutch Meteor Society, and SETI Institute, NASA Ames Research Center, Moffett Field
- Subjects
Multidisciplinary ,Wavelength range ,media_common.quotation_subject ,Light reflection ,Ureilite ,Reflectivity ,Astrobiology ,Meteorite ,Sky ,Asteroid ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Achondrite ,Geology ,media_common - Abstract
On 6 October 2008, a small Earth-bound asteroid designated 2008 TC3 was discovered by the Catalina Sky Survey. Some 19 hours — and many astronomical observations — later it entered the atmosphere and disintegrated at 37 km altitude. No macroscopic fragments were expected to have survived but a dedicated search along the approach trajectory in a desert in northern Sudan has recovered 47 meteorites, fragments of a single body named Almahata Sitta, with a total mass of 3.95 kg. The asteroid and meteorite reflectance spectra identify the asteroid as surface matter from a class 'F' asteroid, material so fragile that it was not previously represented in meteorite collections. To have recovered meteorites from a known class of asteroids is a coup on a par with a successful spacecraft sample-return mission — without the rocket science. On 6 October 2008, a small asteroid designated 2008 TC3 hit the Earth in northern Sudan. Jenniskens et al. searched along the approach trajectory and luckily found 47 bits of a meteorite named Almahata Sitta. Analysis reveals it to be a porous achondrite and a polymict ureilite, and so the asteroid was F-class (dark carbon-rich anomalous ureilites). In the absence of a firm link between individual meteorites and their asteroidal parent bodies, asteroids are typically characterized only by their light reflection properties, and grouped accordingly into classes1,2,3. On 6 October 2008, a small asteroid was discovered with a flat reflectance spectrum in the 554–995 nm wavelength range, and designated 2008 TC3 (refs 4–6). It subsequently hit the Earth. Because it exploded at 37 km altitude, no macroscopic fragments were expected to survive. Here we report that a dedicated search along the approach trajectory recovered 47 meteorites, fragments of a single body named Almahata Sitta, with a total mass of 3.95 kg. Analysis of one of these meteorites shows it to be an achondrite, a polymict ureilite, anomalous in its class: ultra-fine-grained and porous, with large carbonaceous grains. The combined asteroid and meteorite reflectance spectra identify the asteroid as F class3, now firmly linked to dark carbon-rich anomalous ureilites, a material so fragile it was not previously represented in meteorite collections.
- Published
- 2009
41. ICE CHEMISTRY ON OUTER SOLAR SYSTEM BODIES: ELECTRON RADIOLYSIS OF N2-, CH4-, AND CO-CONTAINING ICES
- Author
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Dale P. Cruikshank, Hiroshi Imanaka, Christopher K. Materese, Scott A. Sandford, and Michel Nuevo
- Subjects
Astrochemistry ,Absorption spectroscopy ,Space and Planetary Science ,Chemistry ,Radiolysis ,Inorganic chemistry ,Infrared spectroscopy ,Astronomy and Astrophysics ,Absorption (chemistry) ,Spectroscopy ,Mass spectrometry ,XANES - Abstract
Radiation processing of the surface ices of outer Solar System bodies may be an important process for the production of complex chemical species. The refractory materials resulting from radiation processing of known ices are thought to impart to them a red or brown color, as perceived in the visible spectral region. In this work, we analyzed the refractory materials produced from the 1.2-keV electron bombardment of low-temperature N2-, CH4-, and CO-containing ices (100:1:1), which simulates the radiation from the secondary electrons produced by cosmic ray bombardment of the surface ices of Pluto. Despite starting with extremely simple ices dominated by N2, electron irradiation processing results in the production of refractory material with complex oxygen- and nitrogen-bearing organic molecules. These refractory materials were studied at room temperature using multiple analytical techniques including Fourier-transform infrared spectroscopy, X-ray absorption near-edge structure (XANES) spectroscopy, and gas chromatography coupled with mass spectrometry (GC-MS). Infrared spectra of the refractory material suggest the presence of alcohols, carboxylic acids, ketones, aldehydes, amines, and nitriles. XANES spectra of the material indicate the presence of carboxyl groups, amides, urea, and nitriles, and are thus consistent with the IR data. Atomic abundance ratios for the bulk composition of these residues from XANES analysis show that the organic residues are extremely N-rich, having ratios of N/C ~ 0.9 and O/C ~ 0.2. Finally, GC-MS data reveal that the residues contain urea as well as numerous carboxylic acids, some of which are of interest for prebiotic and biological chemistries.
- Published
- 2015
42. N- ANDO-HETEROCYCLES PRODUCED FROM THE IRRADIATION OF BENZENE AND NAPHTHALENE IN H2O/NH3-CONTAINING ICES
- Author
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Scott A. Sandford, Michel Nuevo, and Christopher K. Materese
- Subjects
Physics ,Astrochemistry ,Pyrimidine ,Astronomy and Astrophysics ,Photochemistry ,medicine.disease_cause ,Astrobiology ,chemistry.chemical_compound ,chemistry ,Meteorite ,Space and Planetary Science ,Pyridine ,medicine ,Molecule ,Benzene ,Ultraviolet ,Naphthalene - Abstract
Aromatic heterocyclic molecules are an important class of molecules of astrophysical and biological significance that include pyridine, pyrimidine, and their derivatives. Such compounds are believed to exist in interstellar and circumstellar environments, though they have never been observed in the gas phase. Regardless of their presence in the gas phase in space, numerous heterocycles have been reported in carbonaceous meteorites, which indicates that they are formed under astrophysical conditions. The experimental work described here shows that N- and O-heterocyclic molecules can form from the ultraviolet (UV) irradiation of the homocyclic aromatic molecules benzene (C6H6) or naphthalene (C10H8) mixed in ices containing H2O and NH3. This represents an alternative way to generate aromatic heterocycles to those considered before and may have important implications for astrochemistry and astrobiology.
- Published
- 2015
43. A detailed study of the amino acids produced from the vacuum UV irradiation of interstellar ice analogs
- Author
-
Didier Blanot, Louis D'Hendecourt, Michel Nuevo, and Geneviève Auger
- Subjects
chemistry.chemical_classification ,Murchison meteorite ,Extraterrestrial Environment ,Ultraviolet Rays ,Interstellar ice ,Carbon Compounds, Inorganic ,Methanol ,Inorganic chemistry ,Ice ,Substrate (chemistry) ,General Medicine ,Amino acid ,chemistry ,Space and Planetary Science ,Ammonia ,Carbonaceous chondrite ,Molecule ,Organic chemistry ,Acid hydrolysis ,Irradiation ,Amino Acids ,Ecology, Evolution, Behavior and Systematics - Abstract
We present a detailed analysis of the variety, quantity and distribution of the amino acids detected in organic residues after acid hydrolysis. Such organic residues are produced in the laboratory after the vacuum ultraviolet (VUV) irradiation of several astrophysically relevant ice mixtures containing H(2)O, CO, CO(2), CH(3)OH, CH(4) and NH(3) at low temperature (10-80 K), and subsequent warm-up to room temperature. We explore five experimental parameters: the irradiation time, the temperature, the ice mixture composition, the photon dose per molecule and the substrate for the ice deposition. The amino acids were detected and identified by ex-situ liquid chromatography analysis of the organic residues formed after warming the photolysed ices up to room temperature. This study shows that in all experiments amino acids are formed. Their total quantities and distribution depend slightly on the experimental parameters explored in the present work, the important requirement to form such molecules being that the starting ice mixtures must contain the four elements C, H, O and N. We also discuss the effects of the chemical treatment needed to detect and identify the amino acids in the organic residues. Finally, these results are compared with meteoritic amino acid data from the carbonaceous chondrite Murchison, and the formation processes of such compounds under astrophysical conditions are discussed.
- Published
- 2006
44. The effects of circularly polarized light on amino acid enantiomers produced by the UV irradiation of interstellar ice analogs
- Author
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Laurent Nahon, Didier Blanot, Michel Nuevo, Emmanuel Dartois, Uwe J. Meierhenrich, Louis Le Sergeant d'Hendecourt, Geneviève Auger, D. Deboffle, Jan Hendrik Bredehöft, G. M. Muñoz Caro, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre de biophysique moléculaire (CBM), Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut de biochimie et biophysique moléculaire et cellulaire (IBBMC), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Francis PERRIN (LFP - URA 2453), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), and Université d'Orléans (UO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Infrared ,Analytical chemistry ,Astrophysics ,010402 general chemistry ,01 natural sciences ,methods: laboratory ,Optics ,0103 physical sciences ,Ultraviolet light ,Irradiation ,010303 astronomy & astrophysics ,Physics ,Alanine ,chemistry.chemical_classification ,polarization ,business.industry ,Interstellar ice ,Astronomy and Astrophysics ,methods: data analysis ,ISM: molecules ,0104 chemical sciences ,Amino acid ,[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry ,molecular processes ,chemistry ,13. Climate action ,Space and Planetary Science ,infrared ,Enantiomer ,Homochirality ,business - Abstract
Two irradiation experiments on interstellar ice analogs at 80 K under interstellar-like conditions were performed with the LURE SU5 synchrotron beamline to assess, for the first time, the photochemical effect of circularly polarized ultraviolet light (UV CPL) at 167 nm (7.45 eV) with right and left polarizations on such ice mixtures. Methods. This effect was measured by determining the enantiomeric excesses (e.e.s) for two amino acids formed in the solid organic residues produced during the subsequent warm-up of the irradiated samples to room temperature: alanine, the most abundant chiral proteinaceous amino acid produced (both polarizations) and 2,3-diaminopropanoic acid (DAP), a non-proteinaceous amino acid (rightpolarization experiment). These excesses were compared to those measured for the same amino acids produced after unpolarized UV irradiation of the same ice mixtures (expected to be zero), in order to determine the contribution of CPL only. A careful estimate of all the associated uncertainties (statistical and systematic errors) was also developed. Results. It appears that the enantiomeric photochemical effect at this wavelength is weak, since both alanine and DAP e.e.s were found to be small, at most of the order of 1% in absolute values, and tends to be inconclusive since the effects obtained for both amino acids and both polarizations are not those expected. In light of these results, the hypothesis that CPL may be one source responsible for the e.e.s measured for such amino acids in some meteorites and, more generally, that CPL may be directly related to the origin of biomolecular homochirality on Earth is discussed.
- Published
- 2006
45. FORMATION OF S-BEARING SPECIES BY VUV/EUV IRRADIATION OF H2S-CONTAINING ICE MIXTURES: PHOTON ENERGY AND CARBON SOURCE EFFECTS
- Author
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Wing-Huen Ip, J.-M. Qiu, Michel Nuevo, A. Jiménez-Escobar, H.-S. Fung, C. C. Chu, Y.-J. Chen, G. M. Muñoz Caro, K.-J. Juang, T. S. Yih, C.-Y. R. Wu, USA, ESP, and TWN
- Subjects
Physics ,chemistry.chemical_classification ,Astrochemistry ,Hydrogen sulfide ,Astronomy and Astrophysics ,Photon energy ,Photochemistry ,chemistry.chemical_compound ,chemistry ,Space and Planetary Science ,Extreme ultraviolet ,Compounds of carbon ,Atomic physics ,Carbonyl sulfide ,Cosmic dust ,Carbon monoxide - Abstract
Carbonyl sulfide (OCS) is a key molecule in astrobiology that acts as a catalyst in peptide synthesis by coupling amino acids. Experimental studies suggest that hydrogen sulfide (H2S), a precursor of OCS, could be present in astrophysical environments. In the present study, we used a microwave-discharge hydrogen-flow lamp, simulating the interstellar UV field, and a monochromatic synchrotron light beam to irradiate CO:H2S and CO2:H2S ice mixtures at 14 K with vacuum ultraviolet (VUV) or extreme ultraviolet (EUV) photons in order to study the effect of the photon energy and carbon source on the formation mechanisms and production yields of S-containing products (CS2, OCS, SO2, etc.). Results show that (1) the photo-induced OCS production efficiency in CO:H2S ice mixtures is higher than that of CO2:H2S ice mixtures; (2) a lower concentration of H2S enhances the production efficiency of OCS in both ice mixtures; and (3) the formation pathways of CS2 differ significantly upon VUV and EUV irradiations. Furthermore, CS2 was produced only after VUV photoprocessing of CO:H2S ices, while the VUV-induced production of SO2 occurred only in CO2:H2S ice mixtures. More generally, the production yields of OCS, H2S2, and CS2 were studied as a function of the irradiation photon energy. Heavy S-bearing compounds were also observed using mass spectrometry during the warm-up of VUV/EUV-irradiated CO:H2S ice mixtures. The presence of S-polymers in dust grains may account for the missing sulfur in dense clouds and circumstellar environments.
- Published
- 2014
46. Local Organising Committee
- Author
-
Michel Nuevo, Amparo M. Gallardo-Moreno, J.A.Mesa Gonzalez, I.Solo de Zaldivar Maldonad, I.Corbacho Cuello, A. Mendez-Vilas, A.Agudo Rodríguez, J.Díaz Álvarez, J. A. Mesa González, M. L. González-Martín, and L.Labajos Broncano
- Published
- 2005
47. THE PHOTOCHEMISTRY OF PYRIMIDINE IN REALISTIC ASTROPHYSICAL ICES AND THE PRODUCTION OF NUCLEOBASES
- Author
-
Scott A. Sandford, Christopher K. Materese, and Michel Nuevo
- Subjects
Physics ,Astrochemistry ,Pyrimidine ,Astronomy and Astrophysics ,Uracil ,Photochemistry ,Thymine ,Nucleobase ,chemistry.chemical_compound ,chemistry ,Deoxyribose ,Space and Planetary Science ,Chondrite ,Cytosine - Abstract
Nucleobases, together with deoxyribose/ribose and phosphoric acid, are the building blocks of DNA and RNA for all known life. The presence of nucleobase-like compounds in carbonaceous chondrites delivered to the Earth raises the question of an extraterrestrial origin for the molecules that triggered life on our planet. Whether these molecules are formed in interstellar/protostellar environments, in small parent bodies in the solar system, or both, is currently unclear. Recent experiments show that the UV irradiation of pyrimidine (C4H4N2) in H2O-rich ice mixtures that contain NH3, CH3OH, or CH4 leads to the formation of the pyrimidine-based nucleobases uracil, cytosine, and thymine. In this work, we discuss the low-temperature UV irradiation of pyrimidine in realistic astrophysical ice mixtures containing H2O, CH3OH, and NH3, with or without CH4, to search for the production of nucleobases and other prebiotic compounds. These experiments show the presence of uracil, urea, glycerol, hexamethylenetetramine, small amino acids, and small carboxylic acids in all samples. Cytosine was only found in one sample produced from ices irradiated with a higher UV dose, while thymine was not found in any sample, even after irradiation with a higher UV dose. Results are discussed to evaluate the role of the photochemistry of pyrimidine in the inventory of organic molecules detected in meteorites and their astrophysical/astrobiological implications.
- Published
- 2014
48. ICE CHEMISTRY ON OUTER SOLAR SYSTEM BODIES: CARBOXYLIC ACIDS, NITRILES, AND UREA DETECTED IN REFRACTORY RESIDUES PRODUCED FROM THE UV PHOTOLYSIS OF N2:CH4:CO-CONTAINING ICES
- Author
-
Hiroshi Imanaka, Douglas W. White, Scott A. Sandford, Michel Nuevo, Christopher K. Materese, and Dale P. Cruikshank
- Subjects
Astrochemistry ,Absorption spectroscopy ,Chemistry ,Photodissociation ,Infrared spectroscopy ,Astronomy and Astrophysics ,Mass spectrometry ,Photochemistry ,Astrobiology ,chemistry.chemical_compound ,Space and Planetary Science ,Absorption (chemistry) ,Spectroscopy ,Carbon monoxide - Abstract
Radiation processing of the surface ices of outer solar system bodies may result in the production of new chemical species even at low temperatures. Many of the smaller, more volatile molecules that are likely produced by the photolysis of these ices have been well characterized by laboratory experiments. However, the more complex refractory material formed in these experiments remains largely uncharacterized. In this work, we present a series of laboratory experiments in which low-temperature (15–20 K) N2:CH4:CO ices in relative proportions 100:1:1 are subjected to UV irradiation, and the resulting materials are studied with a variety of analytical techniques including infrared spectroscopy, X-ray absorption near-edge structure spectroscopy, gas chromatography coupled with mass spectrometry, and high-resolution mass spectroscopy. Despite the simplicity of the reactants, these experiments result in the production of a highly complex mixture of molecules from relatively low-mass volatiles (tens of daltons) to high-mass refractory materials (hundreds of daltons). These products include various carboxylic acids, nitriles, and urea, which are also expected to be present on the surface of outer solar system bodies, including Pluto and other transneptunian objects. If these compounds occur in sufficient concentrations in the ices of outer solar system bodies, their characteristic bands may be detectable in the near-infrared spectra of these objects.
- Published
- 2014
49. VACUUM ULTRAVIOLET EMISSION SPECTRUM MEASUREMENT OF A MICROWAVE-DISCHARGE HYDROGEN-FLOW LAMP IN SEVERAL CONFIGURATIONS: APPLICATION TO PHOTODESORPTION OF CO ICE
- Author
-
Michel Nuevo, K.-J. Chuang, Y.-J. Chen, T. S. Yih, Wing-Huen Ip, G. M. Muñoz Caro, C. C. Chu, and C.-Y. R. Wu
- Subjects
Physics ,Astrochemistry ,Hydrogen ,chemistry.chemical_element ,Astronomy and Astrophysics ,Electromagnetic radiation ,Spectral line ,chemistry ,Space and Planetary Science ,Atomic electron transition ,Irradiation ,Emission spectrum ,Atomic physics ,Absorption (electromagnetic radiation) - Abstract
We report measurements of the vacuum ultraviolet (VUV) emission spectra of a microwave-discharge hydrogen-flow lamp (MDHL), a common tool in astrochemistry laboratories working on ice VUV photoprocessing. The MDHL provides hydrogen Ly-α (121.6 nm) and H2 molecular emission in the 110-180 nm range. We show that the spectral characteristics of the VUV light emitted in this range, in particular the relative proportion of Ly-α to molecular emission bands, strongly depend on the pressure of H2 inside the lamp, the lamp geometry (F type versus T type), the gas used (pure H2 versus H2 seeded in He), and the optical properties of the window used (MgF2 versus CaF2). These different configurations are used to study the VUV irradiation of CO ice at 14 K. In contrast to the majority of studies dedicated to the VUV irradiation of astrophysical ice analogs, which have not taken into consideration the emission spectrum of the MDHL, our results show that the processes induced by photons in CO ice from a broad energy range are different and more complex than the sum of individual processes induced by monochromatic sources spanning the same energy range, as a result of the existence of multistate electronic transitions and discrepancy in absorption cross sections between parent molecules and products in the Ly-α and H2 molecular emission ranges.
- Published
- 2013
50. Photochemistry of interstellar/circumstellar ices as a contributor to the complex organics in meteorites
- Author
-
Scott A. Sandford and Michel Nuevo
- Subjects
chemistry.chemical_classification ,Astrochemistry ,Meteorite ,Space and Planetary Science ,Chemistry ,Astronomy and Astrophysics ,Methods laboratory ,Photochemistry ,Astrobiology ,Nucleobase ,Amino acid - Abstract
The UV irradiation of interstellar/circumstellar ice analogs is known to lead to the formation of organic compounds such as amino acids and maybe nucleobases. In this work, the mechanisms of formation and distribution of amino acids, chosen as tracers for the organic compounds formed in such experiments, are studied and compared with meteoritic data.
- Published
- 2008
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