Evidence for water ice near the lunar poles
Evidence for water ice near the lunar poles
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DOI：
10.1029/2000je001444
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发表时间：
2001-10-25
影响因子：
4.8
通讯作者：
Binder, AB
中科院分区：
文献类型：
--
作者：
Feldman, WC;Maurice, S;Binder, AB
对月球勘探者号热中子和超热中子数据的改进版本进行了研究，以帮助区分月球上氢的潜在输送和留存机制。两极地区提高的空间分辨率显示，氢浓度最高的区域位于永久阴影区。在北极，这些区域由布满众多小型（直径小于约10千米）孤立环形山的崎岖地形组成。这些区域与氢丰度（[H]）的环形区域相邻，该区域的氢丰度仅略高于赤道平均值，但位于大型平底且有阳光照射的极地环形山内。在南极附近，几个直径30千米的永久阴影环形山内氢丰度（[H]）有所增加，而其有阳光照射的相邻区域氢丰度仅略有增加。我们表明，太阳风输送无法解释这些观测结果，因为在两极附近有阳光照射和永久阴影环形山内的温度下，氢的扩散率足够低，太阳风起源无法解释它们之间的差异。我们得出结论，两极附近增加的氢有很大一部分极有可能以水分子的形式存在。
Improved versions of Lunar Prospector thermal and epithermal neutron data were studied to help discriminate between potential delivery and retention mechanisms for hydrogen on the Moon. Improved spatial resolution at both poles shows that the largest concentrations of hydrogen overlay regions in permanent shade. In the north these regions consist of a heavily cratered terrain containing many,small (less than similar to 10-km diameter), isolated craters. These border circular areas of hydrogen abundance ([H]) that is only modestly enhanced above the average equatorial value but that falls within large, flat-bottomed, and sunlit polar craters. Near the south pole, [H] is enhanced within several 30-km-scale craters that are in permanent shade but is only modestly enhanced within their sunlit neighbors. We show that delivery by the solar wind cannot account for these observations because the diffusivity of hydrogen at the temperatures within both sunlit and permanently shaded craters near both poles is sufficiently low that a solar wind origin cannot explain their differences. We conclude that a significant portion of the enhanced hydrogen near both poles is most likely in the form of water molecules.