火星上有液态水存在的雷达证据
R Orosei1, S E Lauro2, E Pettinelli2
1Istituto di Radioastronomia, Istituto Nazionale di Astrofisica, Via Piero Gobetti 101, 40129 Bologna, Italy. roberto.orosei@inaf.it.
Science (New York, N.Y.)
|July 27, 2018
概括
科学家使用雷达数据在火星南极层沉积物下发现了液态水的证据. 这一发现表明红色星球上可能存在稳定的地下水体.
科学领域:
- 星球科学
- 地质学
- 天体生物学
背景情况:
- 在火星上存在液态水是行星科学的一个关键问题.
- 之前的研究表明可能有地下水,特别是在极地, 但直接的证据一直缺乏.
研究的目的:
- 调查火星南极层层沉积物的地下, 寻找液态水的证据.
- 分析雷达数据以发现含水材料的异常.
主要方法:
- 在火星探测器上使用了火星先进地表和离子层探测雷达 (MARSIS).
- 在2012年5月至2015年12月期间调查了澳大利亚.
- 分析了地下雷达反射的介电性.
主要成果:
- 在南极层沉积物中检测到异常明亮的地下雷达反射.
- 定量分析显示该特征的相对介电性高 (>15).
- 明亮的反射和高的导电性与含水材料一致.
结论:
- 观察到的雷达信号强烈地表明火星冰盖下方存在稳定的液态水体.
- 这一发现提供了火星极地底液体水的第一个直接证据.
- 这一发现对火星的潜在可居住性有重大影响.
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