火星表面古气温 - - 来自石热年代学的火星表面古气温
David L Shuster1, Benjamin P Weiss
1Division of Geological and Planetary Sciences, California Institute of Technology, 100-23, Pasadena, CA 91125, USA.
概括
几十亿年来,火星表面的温度一直保持冷. 对火星石的新分析表明,温度很少超过0摄氏度,这表明古老的火星一直很冷.
科学领域:
- 行星科学 行星科学
- 地质地质地质地质地质地
- 热理学 热理学 热理学 热理学
背景情况:
- 了解过去的火星表面温度对于评估这个星球的可居住性至关重要.
- 之前的研究对火星的长期热进化产生了有限的数据.
研究的目的:
- 重建火星石的热史,特别是纳克利特和ALH84001.1.
- 在地质时间尺度上推断火星上过去的近地表温度条件.
主要方法:
- 利用热年代学技术分析石样本.
- 整合已公布的贵重气体和石化数据进行全面分析.
主要成果:
- 纳克莱特石的形成以来,没有任何证据表明其升温超过350°C.
- 计算表明,在过去的40亿年里,火星近地表温度在很大程度上保持在0°C以下.
结论:
- 火星的气候在历史上大部分时间都是冷的.
- 这些发现对在火星上寻找过去的生命有着重大意义.
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