在月球南极的沙克尔顿火山口内挥发性分布的限制
Maria T Zuber1, James W Head, David E Smith
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. zuber@mit.edu
Nature
|June 23, 2012
概括
月球南极附近的沙克尔顿火山口可能含有挥发性物质. 新的数据显示,它的墙壁比它的地板更新鲜,这表明冰可能存在,尽管下坡 regolith运动也是可能的.
科学领域:
- 月球地质学 月球地质学
- 星球科学 星球科学
- 遥感是一种远程传感.
背景情况:
- 在月球南极附近的沙克尔顿火山口是挥发性物质的潜在冷陷.
- 以前对沙克尔顿火山口的挥发性物质含量进行的研究产生了相互矛盾的结果.
- 了解沙克尔顿火山口的组成是月球探索的关键.
研究的目的:
- 为了研究沙克尔顿火山口的地质特征和挥发性潜力.
- 为了解决有关沙克尔顿火山口中挥发物质存在的相互矛盾的解释.
- 用先进的遥感数据分析沙克尔顿火山口的表面和地下组成.
主要方法:
- 从月球轨道器激光高度计 (LOLA) 在月球侦察轨道器 (LRO) 上的观测.
- 对火山口形态的分析,包括墙壁和地板的保存.
- 在1064纳米波长的光度分析以评估表面亮度.
主要成果:
- 沙克尔顿火山口是一个古老的,保存完好的简单火山口.
- 内部墙壁在地质上比火山口的地板和边缘更新鲜.
- 坑底沉积物几乎和边缘一样古老,这表明形成后沉积的最小程度.
- 沙克尔顿的地板比周围的地形更明亮,但在1,064nm时比内部墙壁明亮得多.
结论:
- 石岩在火山口壁上的下坡运动,暴露了更新鲜的材料,主要解释了这些观测.
- 由于阴影造成的太空气候变化的减少为更明亮的石坑地板提供了一个简单的解释.
- 一层薄薄的表面冰层 (约. 1微米厚,20%度) 仍然是对地板亮度的合理替代解释.
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