概括
月球岩66095揭示了显著的水含量,同位素分析表明一些可能与陆地水无法区分,挑战了关于月球水分的先前假设. 这一发现对了解月球上水的起源有重要意义.
科学领域:
- 地质化学 地质化学
- 月球科学 月球科学
- 天体生物学 天体生物学
背景情况:
- 月球岩通常含有很少的水.
- 岩石66095,一个月球样本,拥有异常高的含水量.
- 岩石66095中的水主要在低温下释放出来.
研究的目的:
- 描述月球岩石66095.5的水含量和同位素组成
- 为了调查月球样本中的水的起源.
- 为了比较月球水的同位素标志与陆地水和生.
主要方法:
- 热重力测量分析以确定水释放温度.
- 释放的水的同位素分析 (deltaD和delta(18) O).
- 碳同位素分析 (三角形) 13C).
主要成果:
- 月球岩66095含有140-750ppm的水,其中90%的水在690°C以下释放.
- 低温水具有每毫米SMOW -75至 -140的deltaD值,类似于陆地水.
- 高温水具有每毫米SMOW的-175±25的deltaD.
- delta(18) 每毫升+5±1的O值SMOW与月球酸盐相似,但与陆地生不同.
结论:
- 岩石66095中的水的同位素组成表明,它不仅仅是地球上的起源.
- 有证据表明,月球上的水可能具有与陆地水区分不清的deltaD.
- 这一发现对了解月球上水的起源和演变具有重大意义.
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