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Una transferencia de baja temperatura de ALH84001 desde Marte a la Tierra
B P Weiss1, J L Kirschvink, F J Baudenbacher
1Division of Geological and Planetary Sciences, 170-25, California Institute of Technology, Pasadena, CA 91125, USA. bweiss@gps.caltech.edu
Science (New York, N.Y.)
|October 29, 2000
Resumen
El meteorito marciano ALH84001 muestra evidencia magnética de que nunca excedió los 40°C. Esta temperatura es demasiado baja para esterilizar los microbios, lo que apoya la teoría de la transferencia de vida interplanetaria a través de meteoritos.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Astrobiología Astrobiología.
- La geofísica es la geofísica.
Sus antecedentes:
- Se teoriza que los grandes impactos en Marte expulsan material al espacio.
- Se espera que tales eyecciones calienten el material marciano a altas temperaturas.
- Comprender la historia térmica de los meteoritos es crucial para evaluar las hipótesis de la panspermia.
Objetivo del estudio:
- Para investigar la historia térmica del meteorito marciano ALH84001.1.
- Para evaluar el potencial de supervivencia de la vida microbiana durante la transferencia interplanetaria.
- Para evaluar el papel de los meteoritos en la panspermia.
Principales métodos:
- Análisis del campo magnético del meteorito marciano ALH84001.1.
- Imagen de patrones de magnetización espacialmente heterogéneos.
- Experimentos de calentamiento controlado para determinar los cambios de intensidad de las características magnéticas.
Principales resultados:
- Los patrones de magnetización en ALH84001 están asociados con fracturas y fragmentos de roca.
- Calentar el meteorito a 40°C redujo la intensidad de algunas características magnéticas.
- Esto indica que el interior del meteorito se mantuvo por debajo de 40 ° C desde la eyección de Marte.
Conclusiones:
- La baja historia térmica de ALH84001 apoya su potencial para albergar vida microbiana viable.
- Las temperaturas experimentadas por el meteorito son insuficientes para la esterilización.
- Estos hallazgos refuerzan la hipótesis de la transferencia de vida entre planetas a través de meteoritos.
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