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Distribución del hielo subterráneo de latitudes medias en Marte de nuevos cráteres de impacto
Shane Byrne1, Colin M Dundas, Megan R Kennedy
1Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA. shane@lpl.arizona.edu
Science (New York, N.Y.)
|September 26, 2009
Resumen
Nuevos cráteres de impacto revelan hielo de agua subterránea en las latitudes medias de Marte. Este descubrimiento sugiere que Marte puede contener más hielo de lo que se modeló anteriormente, con potencial para depósitos de hielo profundo.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Geología Geología Geología.
- Astrobiología Astrobiología.
Sus antecedentes:
- El hielo de agua subterránea es un recurso clave para la exploración humana potencial y la comprensión de la historia del clima marciano.
- Estudios anteriores han indicado la presencia de hielo de agua, principalmente en las regiones polares y a poca profundidad.
Objetivo del estudio:
- Para investigar la presencia y accesibilidad de hielo de agua subterránea en las latitudes medias de Marte.
- Para determinar la profundidad y distribución de los depósitos de hielo de agua excavados por cráteres de impacto.
Principales métodos:
- Análisis de imágenes de alta resolución de los orbitadores de Marte para identificar nuevos cráteres de impacto.
- Análisis espectroscópico (infrarrojo cercano) para determinar la composición de los materiales excavados.
- Modelado térmico para evaluar las tasas de sublimación y la pureza del hielo.
- Comparación de las profundidades derivadas de la tabla de hielo con modelos climáticos.
Principales resultados:
- Nuevos cráteres de impacto en cinco sitios de latitudes medias expusieron material brillante y espectralmente distinto consistente con hielo de agua.
- Se observó el desvanecimiento del hielo expuesto durante varios meses, lo que confirma la sublimación.
- El modelado térmico indicó sublimación a escala milimétrica, lo que sugiere hielo limpio y relativamente puro en lugar de hielo dentro de los poros del suelo.
- Las profundidades derivadas de la tabla de hielo se alinean con los modelos que incorporan un mayor contenido de vapor de agua atmosférico pasado.
- Los cráteres probablemente penetraron metros en el hielo, lo que indica una significativa heterogeneidad vertical del hielo.
Conclusiones:
- El hielo de agua subterránea está presente a profundidades de decímetros en las latitudes medias de Marte, accesible a través de cráteres de impacto.
- El hielo observado es relativamente puro y su presencia apoya los modelos de mayor contenido de agua atmosférica pasada.
- Los cráteres de impacto proporcionan un método único para sondear el hielo subterráneo marciano a profundidades no muestreadas anteriormente, revelando heterogeneidad.
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