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Las paleotemperaturas de la superficie marciana a partir de la termocronología de los meteoritos
David L Shuster1, Benjamin P Weiss
1Division of Geological and Planetary Sciences, California Institute of Technology, 100-23, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|July 26, 2005
Resumen
Las temperaturas de la superficie marciana se han mantenido frías durante miles de millones de años. Un nuevo análisis de meteoritos marcianos indica que las temperaturas rara vez superaban los 0 grados C, lo que sugiere un Marte antiguo consistentemente frío.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Geología Geología Geología.
- La termología térmica.
Sus antecedentes:
- Comprender las temperaturas superficiales marcianas pasadas es crucial para evaluar la habitabilidad del planeta.
- Estudios anteriores han dado datos limitados sobre la evolución térmica a largo plazo de Marte.
Objetivo del estudio:
- Para reconstruir las historias térmicas de los meteoritos marcianos, específicamente las nakhlitas y ALH84001.1.
- Para inferir las condiciones pasadas de temperatura cercanas a la superficie en Marte en escalas de tiempo geológicas.
Principales métodos:
- Utilizó técnicas de termocronología para analizar muestras de meteoritos.
- Incorporó datos publicados de gas noble y petrográficos para un análisis exhaustivo.
Principales resultados:
- Los meteoritos de nakhlite no muestran evidencia de calentamiento por encima de 350°C desde su formación.
- Los cálculos sugieren que las temperaturas cercanas a la superficie de Marte se han mantenido en gran medida por debajo de 0 °C durante los últimos 4 mil millones de años.
Conclusiones:
- El clima marciano ha sido predominantemente frío durante la mayor parte de su historia.
- Estos hallazgos tienen implicaciones significativas para la búsqueda de vida pasada en Marte.
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