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月球永久阴影区域的过去范围
Norbert Schörghofer1, Raluca Rufu2
1Planetary Science Institute, Tucson, AZ 85719, USA.
Science advances
|September 13, 2023
概括
月球探测重点,永久阴影区域 (PSRs) 在一个主要的旋转轴重定向后增长. 新的计算表明,这些月球区域的冰块可能比以前估计的更少.
科学领域:
- 月球科学 月球科学
- 行星地质学 行星地质学
- 天体生物学 天体生物学
背景情况:
- 月球上的永久阴影区域 (PSR) 是由于潜在的冰沉积物而成为探索的关键目标.
- 这些区域被认为是在月球自转轴重定向事件发生后形成和扩大,被称为卡西尼状态过渡.
- 对于了解月球冰的分布和历史,PSR的年龄和范围至关重要.
研究的目的:
- 重新计算月球旋转轴的方向和由此产生的永久阴影区域 (PSR) 的范围.
- 调查PSR与变化的地球月球距离有关的时间演变.
- 重新评估月球PSR中冷挥发物的潜在体积.
主要方法:
- 利用最近的地球月球距离时间演变模型来确定月球自转轴的方向.
- 根据旋转轴的变化计算永久阴影区域 (PSR) 的历史范围和面积.
- 分析特定位置的连续阴影的时间,例如Cabeus火山口.
主要成果:
- 月球的旋转轴在远离地球时经历了重大的重定位.
- 永久阴影区域 (PSRs) 的面积大约是21亿年前目前面积的一半,当时太阳衰减值是现在的两倍.
- 超过34亿年前,PSR变得可以忽略不计,Cabeus火山口的撞击地点在大约09亿年前才成为持续的阴影.
结论:
- 永久阴影区域 (PSR) 的形成和增长与月球旋转轴重定向事件直接相关.
- 月球PSR中挥发性物质的冷捕获发生的时间比以前认为的要近.
- 根据这些发现,月球上被冷的冰的估计数量可能需要向下修订.
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