Texto completo disponible sólo en PDF.
Servicios Personalizados
Revista
Articulo
Indicadores
- Citado por SciELO
- Accesos
Links relacionados
- Similares en SciELO
Compartir
TIP. Revista especializada en ciencias químico-biológicas
versión impresa ISSN 1405-888X
TIP vol.8 no.2 Ciudad de México dic. 2005
Artículos de revisión
Búsqueda de vida en Marte
Search of life on Mars
1Lab. de Química de Plasmas y Estudios Planetarios, Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, Ciudad Universitaria, Apdo. Postal 70-543, México D.F. E-mail: navarro@nucleares.unam.mx
La misión astrobiológica más importante que se ha realizado hasta la fecha ha sido sin duda el proyecto Vikingo de la NASA. Esta misión consistió en tres experimentos biológicos especialmente diseñados para la búsqueda de indicadores de vida en las capas superficiales del suelo marciano. Los tres experimentos dieron resultados positivos. Sin embargo, el análisis de materia orgánica en el suelo marciano demostró la ausencia total de carbono orgánico. Este hallazgo fue utilizado como uno de los argumentos más sólidos en contra de la existencia de vida en la superficie del planeta Marte. Como preparación para futuras misiones a Marte en búsqueda de vida es necesario probar los instrumentos en localidades terrestres que pudieran ser ambientes análogos a Marte. Uno de los desiertos más áridos del planeta es el de Atacama, en el norte de Chile. Estudios químicos y microbiológicos del suelo de Atacama sugieren que el corazón del desierto es en realidad un buen análogo de Marte, ya que no posee vida macroscópica y microscópica, tiene niveles muy bajos de materia orgánica, y sus suelos son muy reactivos. En colaboración con científicos franceses y estadounidenses, estamos preparando una misión robótica dirigida por la NASA para la búsqueda de vida pasada o presente en Marte por lo que el Desierto de Atacama en Chile es el escenario para la preparación de esta misión espacial.
Palabras Clave: Ambientes terrestres análogos a Marte; desierto de Atacama; Marte; Misión Vikingo; vida extraterrestre
Undoubtedly the NASA Viking Project has been the most outstanding astrobiological mission conducted so far. This mission consisted of three biological experiments specially designed for the search of life indicators in the upper layers of the Martian soil. The three experiments yielded positive results, however the analysis of organic matter in the Martian soil showed the lack of organic carbon. In order to prepare future missions, it is important to test the instruments beforehand. This could be done in terrestrial places which are similar to Mars. One of such places is the Atacama desert in northern Chile. This desert is one of the most arid places on Earth. Chemical and microbiological studies of the soil in this area suggest that the driest core of the desert is similar to Mars because there is no macroscopic or microscopic life, the amounts of organic matter are low and the soils are very reactive. In collaboration with French and American scientists, we are developing a NASA robotic mission for the search of extinct or extant life in Mars. We are working in the Atacama desert in Chile as the setting to prepare the space mission.
Key words: Terrestrial environments analogs of Mars; Atacama Desert; Mars; Viking Mission; Extraterrestrial life
Agradecimientos
La investigación científica del autor fue realizada con los apoyos económicos otorgados por la UNAM (DGAPA- IN101903), CONACyT (45810-F) y el programa de la NASA (NASA Astrobiology Science and Technology for Exploring Planets Program).
Referencias
1. Lederberg, J. & Sagan, C. Microenvironments for Life on Mars. Proc. Nat. Acad. Sci. (USA) 48, 1473-1475 (1962). [ Links ]
2. Salisbury, F.B. Martian Biology. Science 136, 17-26 (1962). [ Links ]
3. Rea, D.G. Evidence for Life on Mars. Nature 200, 114-116 (1963). [ Links ]
4. Sagan, C. & Lederberg, J. The Prospects for Life on Mars: A Pre-Viking Assessment. Icarus, 28, 291-300 (1976). [ Links ]
5. Soffen, G.A. Status of the Viking Missions. Science 194, 57-59 (1976). [ Links ]
6. Soffen, G.A. Scientific results of the Viking Missions. Science 194, 1274-1276 (1976). [ Links ]
7. Soffen, G.A. The Viking Project. J. Geophys. Res. 82, 3959-3970 (1977). [ Links ]
8. Hess, S.L., Henry, R.M., Leovy, C.B., Ryan, J.A. & Tillman, J.E. Meteorological Results from the Surface of Mars: Viking 1 and 2. J. Geophys. Res . 82, 4559-4574 (1977). [ Links ]
9. Owen, T. et al. The composition of the atmosphere at the surface of Mars. J. Geophys. Res . 82, 4635-4639 (1977). [ Links ]
10. Farmer, C.B., Davies, D.W., Holland, A.L., La Porte, D.D. & Doms, P.E. Mars: Water vapor observations from the Viking orbiters. J. Geophys. Res . 82, 4225-4248 (1977). [ Links ]
11. Levinthal, E.C., Jones, K.L., Fox, P. & Sagan, C. Lander imaging as a detector of life. J. Geophys. Res . 82, 4468-4478 (1977). [ Links ]
12. Klein, H.P. General constraints on the Viking Biolog investigations. Origins of Life 7, 273-279 (1976). [ Links ]
13. Klein, H.P. The Viking biological experiments on Mars. Icarus 34, 666-674 (1978). [ Links ]
14. Klein, H.P. The Viking mission and the search for life on Mars. Rev. Geophys. Space Phys. 17, 1655-1662 (1979). [ Links ]
15. Hubbard, J.S., Hobby, G.L., Horowitz, N.H., Geiger, P.J. & Morelli, F.A. Measurement of 14CO2 assimilation in soils: An experiment for the biological exploration of Mars. Appl. Microbiol. 19, 32-38 (1970). [ Links ]
16. Horowitz, N.H., Hubbard, J.S. & Hobby, G.L. The carbon-assimilation experiment: The Viking Mars Lander. Icarus 16, 147-152 (1972). [ Links ]
17. Hubbard, J.S. The pyrolytic release experiment: Measurement of carbon assimilation. Origins of Life 7, 281-292 (1976). [ Links ]
18. Klein, H.P. et al. The Viking biological investigation: Preliminary results. Science 194, 99-105 (1976). [ Links ]
19. Horowitz, N.H., Hobby, G.L. & Hubbard, J.S. The Viking carbon assimilation experiment: Interim report. Science 194, 1321-1322 (1976). [ Links ]
20. Levin, G.V. Detection of metabolically produced labeled gas: The Viking Mars lander. Icarus 16, 153-166 (1972). [ Links ]
21. Levin, G.V. & Straat, P.A. Labeled release. An experiment in radiorespirometry. Origins of Life 7, 293-311 (1976). [ Links ]
22. Levin, G.V. & Straat, P.A. Viking labeled release biology experiment. Interim results. Science 194, 1322-1329 (1976). [ Links ]
23. Levin, G.V. & Straat, P.A. Recent results from the Viking labeled release experiment on Mars. J. Geophys. Res . 82, 4663-4667 (1977). [ Links ]
24. Oyama, V.I. The gas exchange experiment for life detection: The Viking Mars Lander. Icarus 16, 167-184 (1972). [ Links ]
25. Oyama, V.I., Berdahl, B.J., Carle, G.C., Lehwalt, M.E. & Ginoza, H.S. The search for life on Mars: Viking 1976. Gas changes as indicators of biological activity. Origins of Life 7, 313-333 (1976). [ Links ]
26. Oyama, V.I. & Berdahl, B.J. The Viking gas exchange experiment results from Chryse and Utopia surface samples. J. Geophys. Res . 82, 4669-4676 (1977). [ Links ]
27. Toulmin, P., III et al. Geochemical and mineralogical interpretation of the Viking iorganic chemical results. J. Geophys. Res . 82, 4625-4634 (1977). [ Links ]
28. Simmonds, P.G., Shulman, G.P. & Stembridge, C.H. Organic analysis by pyrolysis-gas chromatography-mass spectrometry. A candidate experiment for the biological exploration of Mars. J. Chromat. Sci. 7, 36-41 (1969). [ Links ]
29. Biemann, K. Test results on the Viking gas chromatograph-mass spectrometry experiment. Origins of Life 5, 417-430 (1974). [ Links ]
30. Biemann, K. et al. The search of organic and volatile inorganic compounds in two surface samples from the Chryse Planitia region on Mars. Science 194, 72-76 (1976). [ Links ]
31. Biemann, K. et al. The search of organic substances and inorganic volatile compounds in the surface of Mars. J. Geophys. Res . 82, 4641-4658 (1977). [ Links ]
32. Biemann, K. The implications and limitations of the findings of the Viking organic analysis experiment. J. Mol. Evol. 14, 65-70 (1979). [ Links ]
33. Zent, A.P. & McKay, C.P. The chemical reactivity of the martian soil and implications for future missions. Icarus 108, 146-157 (1994). [ Links ]
34. McKay, C.P. et al. The Mars oxidant experiment (MOx) for Mars '96. Planet. Space Sci. 46, 769-777 (1998). [ Links ]
35. Yen, A.S., Skim, S.S., Hecht, M.H., Frant, M.S. & Murray, B. Evidence that the reactivity of the martial soil is due to superoxide ions. Science 289, 1909-1912 (2000). [ Links ]
36. Yen, A.S. Unusual reactivity of the martian soil: Oxygen release upon humidification. Lunar and Planetary Science XXXIII, 1760 (2002). [ Links ]
37. Levin, G.V. & Straat, P.A. A search for a nonbiological explanation of the Viking labeled release life detection experiment. Icarus 45, 494-516 (1981). [ Links ]
38. Levin, G.V. & Straat, P.A. Antarctic Soil No. 726 and Implications for the Viking Labeled Release Experiment. J. Theor. Biol. 91, 41-45 (1981). [ Links ]
39. Rieder, R. et al. The Chemical Composition of Martian Soil and Rocks Returned by the Mobile Alpha Proton X-ray Spectrometer: Preliminary Results from the X-ray Mode. Science , 278, 1771-1774 (1997). [ Links ]
40. Kerr, R.A. Planetary science - A wet early Mars seen in salty deposits. Science 303, 1450 (2004). [ Links ]
41. Butler, D. Mars satellite flies into hunt for lost Beagle 2. Nature 427, 5 (2004). [ Links ]
42. Horowitz, N.H. et al. Sterile soil from Antarctic: Organic analysis. Science 164, 1054-1056 (1969). [ Links ]
43. Horowitz, N.H., Cameron, R.E. & Hubbard, J.S. Microbiology of the Dry Valleys of Antarctic. Science 176, 242-245 (1972). [ Links ]
44. Friedmann, E.I. & Ocampo, R. Endolithic blue green-algae in the Dry Valleys: Primary producers in the Antarctic Desert ecosystem. Science 193, 1247-1249 (1976). [ Links ]
45. Friedmann, E.I. Endolithic microorganisms in the Antarctic cold desert. Science 215, 1045-1053 (1982). [ Links ]
46. McGinnies, W.G., Goldman, B.J. & Paylore, P. Deserts of the World (University of Arizona Press, Tucson, 788 pp., 1968) [ Links ]
47. Börgel, R.O. The coastal desert of Chile. En Coastal Deserts, Their Natural and Human Environments (eds. Amiran D.H. & Wilson, A.W.) 111-114 (University of Arizona Press, Tucson, 1973). [ Links ]
48. Caviedes, C.L. A climatic profile of the north Chilean desert at latitude 20 south. En Coastal Deserts, Their Natural and Human Environments (eds. Amiran D.H. &Wilson, A.W. ) 115-121 (University of Arizona Press, Tucson, 1973). [ Links ]
49. Miller, A. The climate of Chile. En World Survey of Climatology, Vol. 12: Climate of Centraland South America (ed. Schwerdfeger, W.) 113-145 (Elsevier, Amsterdam, 1976). [ Links ]
50. Rundel, P.W. et al. The phytogeography and ecology of the coastal Atacama and Peruvian deserts. Aliso 13(1), 1-49 (1991). [ Links ]
51. Lettau, H. Dynamics and energetic factors which cause and limit aridity along South America's Pacific coast. En World Survey of Climatology, Vol. 12: Climate of Central and South America (ed. Schwerdfeger, W.) 188-192 (Elsevier, Amsterdam, 1976). [ Links ]
52. Rutllant, J. & Ulriksen, P. Boundary layer dynamics of the extremely arid northern part of Chile: the Antofagasta Field Experiment. Boundary Layer Meteor. 17, 41-55 (1979). [ Links ]
53. Abreu, M.L. & Bannon, P. Dynamics of the South American coastal desert. J. Atmos. Sci. 50, 2952-2964 (1993). [ Links ]
54. Rutllant, J., Fuenzalida, H., Torres R. & Figueroa, D. Ocean-atmosphere-land interaction in the Antofagasta Region (Chile, 23 S): the DICLIMA field experiment. Rev. Chilena Historia Natural 71, 405-427 (1998). [ Links ]
55. Rutllant, J. et al. Coastal climate dynamics of the Antofagasta region (Chile, 23 S): the 1997-1998 DICLIMA experiment. En 6th International Conference on Southern Hemisphere Meteorology and Oceanography, Santiago, 3-7 April 2000, (2000), American Meteorological Society, Boston, pp. 268-269 (2000). [ Links ]
56. Betancourt, L.J., Latorre, C., Rech, J. A., Quade, J. & Rylander, K. AA 22,000-Year Record of Monsoonal Precipitation from Northern Chile's Atacama Desert. Science 289, 1542-1546 (2000). [ Links ]
57. Bobst, A.L. et al. A 106 ka paleoclimate record from drill core of the Salar de Atacama, northern Chile. Palaeogeography Palaeoclimatology Palaeoecology 173, 21-42 (2001). [ Links ]
58. Lowenstein, T.K. et al. An assessment of stratigraphic completeness in climate-sensitive closed-basin lake sediments: Salar de Atacama, Chile. J. Sedimentary Res. 73, 91-104 (2003). [ Links ]
59. Mckay, C.P. et al. Temperature and Moisture Conditions for Life in the Extreme Arid Region of the Atacama Desert: Four Years of Observations Including the El Niño of 1997-1998. Astrobiology 3, 393-406 (2003). [ Links ]
60. Ericksen, E. The Chilean nitrate deposits. Amer. Scientist 71, 366-374 (1983). [ Links ]
61. Berger, I.A. & Cooke, R.U. The origin and distribution of salts on alluvial fans in the Atacama Desert, Northern Chile. Earth Surface Processes Landforms 22, 581-600 (1997). [ Links ]
62. Bõhlke, J.K., Ericksen, G.E. & Revesz, K. Stable isotope evidence for an atmospheric origin of desert nitrate deposits in northern Chile and southern California, USA. Chemical Geology 136, 135-152 (1997). [ Links ]
63. Navarro-González, R., Molina, P. & McKay, C.P. Organic Characterization of Atacama Soils along a North-To-South Precipitation Gradient, Proc. 3 rd European Workshop on Exo/ Astrobiology. Mars: The search for life, Madrid (Spain), 18-20 November 2003, ESA Special Publication SP-545, pp. 245-248 (2004). [ Links ]
64. Navarro-González, R. et al. Mars-Like Soils in the Yungay Area, the Driest Core of the Atacama Desert in Northern Chile. En Life in the Universe (eds. Chela-Flores, J., Owen, T., Raulin, F. & Seckbach, J.) 211-216 (Kluwer Academic Pub., Dordrecht, 2004). [ Links ]
65. Navarro-González, R. et al. Mars-like soils in the Atacama Desert, Chile, and the dry limit of microbial life. Science 302, 1018-1021 (2003). [ Links ]
Recibido: 21 de Septiembre de 2005; Aprobado: 08 de Noviembre de 2005