低温转移ALH84001从火星到地球
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
概括
火星石ALH84001显示磁性证据表明它从未超过40°C. 这种温度太低,无法杀菌微生物,支持行星间生命通过石传递的理论.
科学领域:
- 行星科学 行星科学
- 天体生物学 天体生物学
- 地质物理学 地质物理学
背景情况:
- 理论上,火星上的大型撞击会将物质抛出太空.
- 预计这种喷射会使火星物质升温到高温.
- 了解石的热史对于评估泛精子学假说至关重要.
研究的目的:
- 为了调查火星石ALH84001.1的热史.
- 评估在星际转移期间微生物生命生存的潜力.
- 为了评估石在潘斯珀米亚中的作用.
主要方法:
- 分析火星石ALH84001.1的磁场.
- 空间异质磁化模式的成像.
- 控制加热实验以确定磁特征强度变化.
主要成果:
- 在ALH84001中磁化模式与断裂和岩石碎片有关.
- 将石加热到40°C可以降低某些磁特征的强度.
- 这表明石的内部自从从火星喷射出来以来一直低于40°C.
结论:
- ALH84001的低热历史支持其潜力,以庇护可行的微生物生命.
- 石所经历的温度不足以进行灭菌.
- 这些发现支持了行星之间通过石传递生命的假设.
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