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1.
Life Sci Space Res (Amst) ; 41: 86-99, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38670657

RESUMEN

Recent discoveries related to the habitability and astrobiological relevance of the outer Solar System have expanded our understanding of where and how life may have originated. As a result, the Icy Worlds of the outer Solar System have become among the highest priority targets for future spacecraft missions dedicated to astrobiology-focused and/or direct life detection objectives. This, in turn, has led to a renewed interest in planetary protection concerns and policies for the exploration of these worlds and has been a topic of discussion within the COSPAR (Committee on Space Research) Panel on Planetary Protection. This paper summarizes the results of those discussions, reviewing the current knowledge and the history of planetary protection considerations for Icy Worlds as well as suggesting ways forward. Based on those discussions, we therefore suggest to (1) Establish a new definition for Icy Worlds for Planetary Protection that captures the outer Solar System moons and dwarf planets like Pluto, but excludes more primitive bodies such as comets, centaurs, and asteroids: Icy Worlds in our Solar System are defined as all bodies with an outermost layer that is believed to be greater than 50 % water ice by volume and have enough mass to assume a nearly round shape. (2) Establish indices for the lower limits of Earth life with regards to water activity (LLAw) and temperature (LLT) and apply them into all areas of the COSPAR Planetary Protection Policy. These values are currently set at 0.5 and -28 °C and were originally established for defining Mars Special Regions; (3) Establish LLT as a parameter to assign categorization for Icy Worlds missions. The suggested categorization will have a 1000-year period of biological exploration, to be applied to all Icy Worlds and not just Europa and Enceladus as is currently the case. (4) Have all missions consider the possibility of impact. Transient thermal anomalies caused by impact would be acceptable so long as there is less than 10-4 probability of a single microbe reaching deeper environments where temperature is >LLT in the period of biological exploration. (5) Restructure or remove Category II* from the policy as it becomes largely redundant with this new approach, (6) Establish that any sample return from an Icy World should be Category V restricted Earth return.


Asunto(s)
Exobiología , Medio Ambiente Extraterrestre , Planetas , Sistema Solar , Vuelo Espacial , Nave Espacial , Historia del Siglo XX
3.
Gynecol Obstet Fertil Senol ; 47(1): 63-78, 2019 01.
Artículo en Francés | MEDLINE | ID: mdl-30579968

RESUMEN

OBJECTIVE: To determine a minimum threshold of human resources (midwives, obstetricians and gynecologists, anesthesiology and intensive care units, pediatricians) to ensure the safety and quality of unplanned activities in Obstetrics and Gynecology. MATERIALS AND METHODS: Consultation of the MedLine database, the Cochrane Library and the recommendations of authorities. Meetings of representative members in different modes of practice (university, hospital, liberal) under the aegis of and belonging to the French College of Obstetricians and Gynecologists (CNGOF), the French Society of Anesthesia and Resuscitation (SFAR), the French Society of Neonatalogy (SFN), the French Society of Perinatal Medicine (SFMP), the French College of Midwives (CNSF), the French Federation of Perinatal Care Networks (FFRSP) with elaboration of a re-read text by external experts, in particular by the members of the Boards of Directors of these authorities and of Club of Anesthesiology-Intensive Care Medicine in Obstetrics (CARO). RESULTS: Different minimum thresholds for each category of caregivers were proposed based on the number of births/year. These proposed minimum thresholds can be modulated upwards according to the types (level I, IIA, IIB or III) or the activity (existence of an emergency reception service, maternal-fetal and/or surgical activity of resort or referral). Due to peak activity and the possibility of unpredictable concomitance of urgent medical procedures, it is necessary that organizations plan to use resource persons. The occupancy rate of the target beds of a maternity ward must be 85%. CONCLUSION: These proposed minimum thresholds are intended to help caregivers providing non-scheduled perinatal as well as Obstetrics and Gynecology care to make the most of the human resources allocated to institutional bodies to ensure their safety and quality.


Asunto(s)
Consenso , Ginecología/métodos , Obstetricia/métodos , Anestesiología , Servicios Médicos de Urgencia , Femenino , Francia , Fuerza Laboral en Salud , Humanos , Unidades de Cuidados Intensivos , Comunicación Interdisciplinaria , MEDLINE , Partería , Pediatría , Embarazo , Sociedades Médicas
4.
J Chromatogr A ; 1368: 211-6, 2014 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-25441355

RESUMEN

With the European Space Agency's Rosetta space mission to comet 67P/Churyumov-Gerasimenko, a gas chromatograph, part of the COmetary Sampling And Composition (COSAC) experiment, travelled for about 10 years in the interplanetary medium before operating at the surface of the cometary nucleus in November 2014. During its journey in space, the instrument was exposed to the constraining conditions of the interplanetary medium, including reduced environmental pressures. In order to estimate the potential influence of this severe condition on the chromatographic capillary columns, their stationary phase and the subsequent separation capability, a set of flight spare columns were kept under reduced environmental pressure in the laboratory for the same duration as the probe sent to the comet. The columns' analytical performances were evaluated recently and compared to the original ones obtained just before the launch of the Rosetta probe. The results presented here show that the chromatographic performances of the spare chromatographic columns were not altered in time. From this result, it can be expected that the flight instrument will perform nominally for the analysis of the first cometary nucleus sample to be collected ever, and that the preparation of the interpretation of the data to be taken at the cometary surface nucleus can be done through calibration of these spare columns, and other spare components of the instrument.


Asunto(s)
Cromatografía de Gases/instrumentación , Cromatografía de Gases/métodos , Presión
5.
Faraday Discuss ; 147: 419-27; discussion 527-52, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21302559

RESUMEN

A laboratory study based on the chemical transformation that Titan's aerosol analogues suffer when placed under putative surface conditions of the satellite was performed. In order to understand the role that aqueous ammonia may play on the chemical transformation of atmospheric aerosols once they reach the surface, we synthesized laboratory analogues of Titan's aerosols from an N2 : CH4 (98 : 2) mixture irradiated at low temperatures under a continuous flow regime by a cold plasma discharge of 180 W. The analogues were recovered, partitioned in several 10.0 mg samples and placed inside different ammonia concentrations during 10 weeks at temperatures as low as those reported for Titan's surface. After a derivatization process performed to the aerosols' refractory phase with MTBSTFA in DMF, the products were identified and quantified using a GC-MS system. We found derived residues related to amino acids as well as urea. The simplest amino acids aminoethanoic acid (glycine) and 2-aminopropanoic acid (alanine) as well as diaminomethanal (urea), are found regardless of the ammonia concentration and temperature value to which the aerosol analogues were exposed. Our results have important astrobiological implications to Titan's environment particularly if the existence of the suggested subsurface water-ammonia mixture and its deposition on the satellite's surface is validated.

6.
Astrobiology ; 9(6): 543-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19663761

RESUMEN

The detection and identification of organic molecules on Mars are of primary importance to establish the existence of a possible ancient prebiotic chemistry or even biological activity. The harsh environmental conditions at the surface of Mars could explain why the Viking probes-the only efforts, to date, to search for organics on Mars-detected no organic matter. To investigate the nature, abundance, and stability of organic molecules that could survive such environmental conditions, we developed a series of experiments that simulate martian surface environmental conditions. Here, we present results with regard to the impact of solar UV radiation on various carboxylic acids, such as mellitic acid, which are of astrobiological interest to the study of Mars. Our results show that at least one carboxylic acid, mellitic acid, could produce a resistant compound-benzenehexacarboxylic acid-trianhydride (C(12)O(9))-when exposed to martian surface radiation conditions. The formation of such products could contribute to the presence of organic matter in the martian regolith, which should be considered a primary target for in situ molecular analyses during future surface missions.


Asunto(s)
Ácidos Carboxílicos/química , Evolución Química , Medio Ambiente Extraterrestre/química , Marte , Rayos Ultravioleta , Benzoatos/química , Ácido Benzoico/química , Ácido Oxálico/química , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo
7.
J Chromatogr A ; 1131(1-2): 215-26, 2006 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-16919657

RESUMEN

In the frame of the calibration of the aerosol collector and pyrolyser, and gas chromatography-mass spectrometry experiments of the Huygens probe arrived at Titan, systematic experimental studies were led to estimate the influence of the operating conditions on the analyses that should have been achieved in the Titan's atmosphere. The primary objective of this study was to estimate the influence of operating conditions variations induced by (i) instrumental modifications made shortly before the probe launch which can have changed the operating pressures; (ii) the change of the probe environmental conditions (pressure, temperature) during its descent in the atmosphere; (iii) a possible deviation of pressure and temperature regulations from their nominal values because of the long journey of the instrument in space, or of other external events. The secondary objective of this work was to create an analytical database that can be used as a reference to treat the chromatograms obtained in situ, and help to identify chromatographically the analyzed species, complementary to mass spectrometry. Beyond the application to a specific instrument, this work was also useful to experimentally estimate the fundamental evolution of the separation as a function of the changes of operating conditions with time. The obtained results show (i) the significant influence of inlet and outlet pressure variation on the time of analysis, but not on the separation power. It thus enables to significantly shorten the analysis duration, and thus to analyze more compounds within the fixed time of analysis of the instrument; (ii) the significant influence of temperature on the retention. In this frame, the enthalpies of exchange between the gas phase and the stationary phase of the species were determined to be used to retrieve the analyzed species in case of deviation of the operating temperature; (iii) that the possible aging of the columns does not have influence on the columns efficiency and separation power; (iv) the analytical capabilities of the gas chromatography-mass spectrometry experiment within operating conditions representative of those encountered in situ. Finally, in spite of possible operating condition changes, it is shown that results coming from the gas chromatograph-mass spectrometer experiment, which are currently under analysis, could bring important information on the Titan's atmosphere and its history.


Asunto(s)
Atmósfera/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Saturno , Temperatura , Presión Atmosférica , Medio Ambiente Extraterrestre , Meteoroides
8.
Chirality ; 18(4): 279-95, 2006 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-16534802

RESUMEN

The target of the in-situ research of optical activity in extraterrestrial samples stimulated an extended investigation of a GC-MS method based on the derivatization of amino acids by using a mixture of perfluorinated alcohols and perfluorinated anhydrides. Amino acids are converted to their N(O,S)-perfluoroacyl perfluoroalkyl esters in a single-step procedure, using different combinations of the derivatization reagents trifluoroacetic anhydride (TFAA)-2,2,2-trifluoro-1-ethanol (TFE), TFAA-2,2,3,3,4,4,4-heptafluoro-1-butanol (HFB), and heptafluorobutyric anhydride (HFBA)-HFB. The derivatives obtained are analyzed using two different chiral columns: Chirasil-L-Val and gamma-cyclodextrin (Rt-gamma-DEXsa) stationary phases which show different and complementary enantiomeric selectivity. The mass spectra of the derivatives are studied, and mass fragmentation patterns are proposed: significant fragment ions can be identified to detect amino acid derivatives. The obtained results are compared in terms of the enantiomeric separation achieved and mass spectrometric response. Linearity studies and the measurement of the limit of detection (LOD) show that the proposed method is suitable for a quantitative determination of enantiomers of several amino acids. The use of the programmed temperature vaporiser (PTV) technique for the injection of the untreated reaction mixture is a promising method for avoiding manual treatment of the sample and decreasing the LOD.


Asunto(s)
Aminoácidos/análisis , Vuelo Espacial , Acilación , Aminoácidos/química , Calibración , Esterificación , Ésteres/análisis , Ésteres/química , Cromatografía de Gases y Espectrometría de Masas , Estructura Molecular , Estándares de Referencia , Estereoisomerismo , Factores de Tiempo , Volatilización
9.
Nature ; 438(7069): 796-9, 2005 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-16319825

RESUMEN

Aerosols in Titan's atmosphere play an important role in determining its thermal structure. They also serve as sinks for organic vapours and can act as condensation nuclei for the formation of clouds, where the condensation efficiency will depend on the chemical composition of the aerosols. So far, however, no direct information has been available on the chemical composition of these particles. Here we report an in situ chemical analysis of Titan's aerosols by pyrolysis at 600 degrees C. Ammonia (NH3) and hydrogen cyanide (HCN) have been identified as the main pyrolysis products. This clearly shows that the aerosol particles include a solid organic refractory core. NH3 and HCN are gaseous chemical fingerprints of the complex organics that constitute this core, and their presence demonstrates that carbon and nitrogen are in the aerosols.


Asunto(s)
Medio Ambiente Extraterrestre/química , Compuestos Orgánicos/análisis , Saturno , Aerosoles/química , Amoníaco/análisis , Atmósfera/química , Carbono/análisis , Cromatografía de Gases y Espectrometría de Masas , Gases/análisis , Gases/química , Calor , Cianuro de Hidrógeno/análisis , Nitrógeno/análisis
10.
Nature ; 438(7069): 779-84, 2005 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-16319830

RESUMEN

Saturn's largest moon, Titan, remains an enigma, explored only by remote sensing from Earth, and by the Voyager and Cassini spacecraft. The most puzzling aspects include the origin of the molecular nitrogen and methane in its atmosphere, and the mechanism(s) by which methane is maintained in the face of rapid destruction by photolysis. The Huygens probe, launched from the Cassini spacecraft, has made the first direct observations of the satellite's surface and lower atmosphere. Here we report direct atmospheric measurements from the Gas Chromatograph Mass Spectrometer (GCMS), including altitude profiles of the constituents, isotopic ratios and trace species (including organic compounds). The primary constituents were confirmed to be nitrogen and methane. Noble gases other than argon were not detected. The argon includes primordial 36Ar, and the radiogenic isotope 40Ar, providing an important constraint on the outgassing history of Titan. Trace organic species, including cyanogen and ethane, were found in surface measurements.


Asunto(s)
Atmósfera/química , Medio Ambiente Extraterrestre/química , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Vuelo Espacial , Argón/análisis , Carbono/análisis , Carbono/química , Isótopos/análisis , Metano/análisis , Metano/química , Nitrógeno/análisis , Nitrógeno/química , Vuelo Espacial/instrumentación
11.
Science ; 308(5724): 975-8, 2005 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-15894528

RESUMEN

Temperatures obtained from early Cassini infrared observations of Titan show a stratopause at an altitude of 310 kilometers (and 186 kelvin at 15 degrees S). Stratospheric temperatures are coldest in the winter northern hemisphere, with zonal winds reaching 160 meters per second. The concentrations of several stratospheric organic compounds are enhanced at mid- and high northern latitudes, and the strong zonal winds may inhibit mixing between these latitudes and the rest of Titan. Above the south pole, temperatures in the stratosphere are 4 to 5 kelvin cooler than at the equator. The stratospheric mole fractions of methane and carbon monoxide are (1.6 +/- 0.5) x 10(-2) and (4.5 +/- 1.5) x 10(-5), respectively.


Asunto(s)
Hidrocarburos , Metano , Nitrilos , Saturno , Atmósfera , Monóxido de Carbono , Medio Ambiente Extraterrestre , Nave Espacial , Temperatura , Viento
12.
J Chromatogr A ; 1071(1-2): 255-61, 2005 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15865201

RESUMEN

Gas chromatography-mass spectrometry (GC-MS) will be used in future space exploration missions, in order to seek organic molecules at the surface of Mars, and especially potential chemical indicators of life. Carboxylic acids are among the most expected organic species at the surface of Mars, and they could be numerous in the analysed samples. For this reason, a chemometric method was applied to support the interpretation of chromatograms of carboxylic acid mixtures. The method is based on AutoCovariance Function (ACVF) in order to extract information on the sample--number and chemical structure of the components--and on separation performance. The procedure was applied to standard samples containing targeted compounds which are among the most expected to be present in the Martian soil: n-alkanoic and benzene dicarboxylic acids. ACVF was computed on the obtained chromatograms and plotted versus retention time: peaks of the ACVF plot can be related to specific molecular structures and are diagnostic for chemical identification of compounds.


Asunto(s)
Exobiología , Cromatografía de Gases y Espectrometría de Masas/métodos , Marte , Suelo/análisis
13.
Science ; 307(5713): 1247-51, 2005 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-15618486

RESUMEN

Stratospheric temperatures on Saturn imply a strong decay of the equatorial winds with altitude. If the decrease in winds reported from recent Hubble Space Telescope images is not a temporal change, then the features tracked must have been at least 130 kilometers higher than in earlier studies. Saturn's south polar stratosphere is warmer than predicted from simple radiative models. The C/H ratio on Saturn is seven times solar, twice Jupiter's. Saturn's ring temperatures have radial variations down to the smallest scale resolved (100 kilometers). Diurnal surface temperature variations on Phoebe suggest a more porous regolith than on the jovian satellites.


Asunto(s)
Saturno , Atmósfera , Carbono , Medio Ambiente Extraterrestre , Hidrógeno , Metano , Nave Espacial , Análisis Espectral , Temperatura , Viento
14.
Science ; 305(5690): 1582-6, 2004 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-15319491

RESUMEN

The Composite Infrared Spectrometer observed Jupiter in the thermal infrared during the swing-by of the Cassini spacecraft. Results include the detection of two new stratospheric species, the methyl radical and diacetylene, gaseous species present in the north and south auroral infrared hot spots; determination of the variations with latitude of acetylene and ethane, the latter a tracer of atmospheric motion; observations of unexpected spatial distributions of carbon dioxide and hydrogen cyanide, both considered to be products of comet Shoemaker-Levy 9 impacts; characterization of the morphology of the auroral infrared hot spot acetylene emission; and a new evaluation of the energetics of the northern auroral infrared hot spot.


Asunto(s)
Dióxido de Carbono , Hidrocarburos , Cianuro de Hidrógeno , Júpiter , Acetileno , Atmósfera , Etano , Medio Ambiente Extraterrestre , Nave Espacial , Análisis Espectral , Temperatura
15.
Nature ; 427(6970): 132-5, 2004 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-14712270

RESUMEN

The Earth's equatorial stratosphere shows oscillations in which the east-west winds reverse direction and the temperatures change cyclically with a period of about two years. This phenomenon, called the quasi-biennial oscillation, also affects the dynamics of the mid- and high-latitude stratosphere and weather in the lower atmosphere. Ground-based observations have suggested that similar temperature oscillations (with a 4-5-yr cycle) occur on Jupiter, but these data suffer from poor vertical resolution and Jupiter's stratospheric wind velocities have not yet been determined. Here we report maps of temperatures and winds with high spatial resolution, obtained from spacecraft measurements of infrared spectra of Jupiter's stratosphere. We find an intense, high-altitude equatorial jet with a speed of approximately 140 m s(-1), whose spatial structure resembles that of a quasi-quadrennial oscillation. Wave activity in the stratosphere also appears analogous to that occurring on Earth. A strong interaction between Jupiter and its plasma environment produces hot spots in its upper atmosphere and stratosphere near its poles, and the temperature maps define the penetration of the hot spots into the stratosphere.

16.
J Chromatogr A ; 999(1-2): 165-74, 2003 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-12885061

RESUMEN

A solid-liquid extraction method able to perform in situ extraction of organic compounds on Mars is proposed. The extraction efficiency of various organic solvents was tested and compared to that of water. The selected key compounds are molecules of exobiological interest: glycine, alanine, serine, glutamic acid, oxalic acid, benzoic acid, phthalic acid, isophthalic acid, terephthalic acid and 1,3,5-benzenetricarboxylic acid. Among the organic solvents, propanol gives the highest yield of extraction for all the targeted compounds except for benzoic acid. A mixture of propanol and ethyl acetate increases significantly the extraction yield of benzoic acid. The extraction time was considerably reduced (140 h to 15 min) by using sonication. The method is discussed for an easy automation with coupling to an in situ GC-MS space instrument.


Asunto(s)
Exobiología , Marte , Suelo/análisis , Cromatografía de Gases y Espectrometría de Masas
17.
J Chromatogr A ; 982(2): 303-12, 2002 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-12489887

RESUMEN

As part of the development of the European Space Agency Rosetta space mission to investigate a cometary nucleus, the selection of columns dedicated to the gas chromatographic subsystem of the Cometary Sampling and Composition (COSAC) experiment was achieved. Once the space probe launched, these columns will be exposed to the harsh environmental constraints of space missions: vibrations, radiation (by photons or energetic particles), space vacuum, and large temperature range. In order to test the resistance of the flight columns and their stationary phases, the columns were exposed to these rough conditions reproduced in the laboratory. The comparison of the analytical performances of the columns, evaluated prior and after the environmental tests, demonstrated that all the columns withstand space constraints, and that their analytical properties were preserved. Therefore, all the selected capillary columns, even having porous layer or chiral stationary phases, were qualified for space exploration.


Asunto(s)
Cromatografía de Gases/instrumentación , Meteoroides , Vuelo Espacial
18.
Chirality ; 14(6): 527-32, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12112349

RESUMEN

Two different methods of derivatization were studied in order to select and optimize one for the in situ enantiomeric separation of amino acids present in Martian samples. The method, using DMF-DMA [N,N-dimethylformamide dimethyl acetal], is simple and easily automated. However, byproducts of the reaction interfere in the gas chromatograms and mass spectrometry detection is needed for in situ analysis. The chloroformate derivatization has several advantages, including the use of achiral robust capillary column, room temperature reaction, and short analysis. The choice of the definitive derivatization method will depend on the energy and time devoted to the analysis of amino acids in the next Mars exploration missions.


Asunto(s)
Dimetilformamida/análogos & derivados , Origen de la Vida , Vuelo Espacial , Aminoácidos/química , Aminoácidos/aislamiento & purificación , Formiatos , Cromatografía de Gases y Espectrometría de Masas , Marte , Estereoisomerismo
19.
J Chromatogr A ; 953(1-2): 165-73, 2002 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-12058930

RESUMEN

The cometary sampling and composition (COSAC) experiment is one of the principal experiments of the surface lander probe of the European Space Agency Rosetta mission to be launched in January 2003. The instrument is designed for the in situ chemical analysis of a cometary nucleus as the details of the nucleus composition are of primary importance for understanding both the formation of the solar system, and the origin of life on Earth. The COSAC experiment consists of an evaporation/pyrolysis device and two analytical systems: a multi-column gas chromatograph and a high-resolution time-of-flight mass spectrometer which may either be operated alone or in a coupled mode. The gas chromatograph includes five general purpose chromatographic columns and three chiral ones, all mounted in parallel. Taking into account the chemical species potentially present in the cometary nucleus as well as the space constraints, a set of five complementary columns was selected to perform the separation and identification of the compounds present in the cometary nucleus. This set of columns includes a carbon molecular sieve porous-layer open tubular (PLOT) column used for the separation of both the noble and other permanent gases, and the C1-C2 hydrocarbons. A second PLOT column uses a divinylbenzene-ethylene glycol-dimethylacrylate porous polymer as stationary phase for the analysis of a wide range of C1-C2 organic molecules, Two complementary wall-coated open tubular (WCOT) columns with polydimethylsiloxane (PDMS) liquid stationary phases, one containing cyanopropyl-phenylsiloxane and the other diphenylsiloxane groups, are designed to target the same range of organic compounds (C3-C7) which could be representative of the widest range of cometary compounds. A third WCOT column with an apolar stationary phase made of non-substituted PDMS is used for the separation and identification of higher-molecular-mass compounds (up to C10) and aromatic species (monoaromatic and polyaromatic). This paper describes these five general-purpose capillary PLOT and WCOT columns, selected to be used in the COSAC GC system. The analytical capabilities are examined with a special emphasis on the exobiological and planetological implications.


Asunto(s)
Cromatografía de Gases/métodos , Meteoroides , Gases/análisis , Hidrocarburos/análisis , Peso Molecular
20.
Adv Space Res ; 27(2): 195-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11605632

RESUMEN

If there is, or ever was, life in our solar system beyond the Earth, Mars is the most likely place to search for. Future space missions will have then to take into account the detection of prebiotic molecules or molecules of biological significance such as amino acids. Techniques of analysis used for returned samples have to be very sensitive and avoid any chemical or biological contamination whereas in situ techniques have to be automated, fast and low energy consuming. Several possible methods could be used for in situ amino acid analyses on Mars, but gas chromatography would likely be the most suitable. Returned samples could be analyzed by any method in routine laboratory use such as gas chromatography, already successfully performed for analyses of organic matter including amino acids from martian meteorites. The derivatization step, which volatilizes amino acids to perform both in situ and laboratory analysis by gas chromatography, is discussed here.


Asunto(s)
Aminoácidos/análisis , Exobiología/instrumentación , Marte , Cromatografía de Gases , Medio Ambiente Extraterrestre , Suelo/análisis , Vuelo Espacial/instrumentación
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