まとめ
月面岩66095は水分を大量に含有しており,同位体分析により,一部が地上の水分と区別できない可能性があることが示唆され,月面水分化に関する以前の仮定に異議を唱える. この発見は,月の水の起源を理解するための意味を持つ.
科学分野:
- 地質化学 地質化学
- 月科学 月科学 月科学
- 天体生物学 アストロバイオロジー
背景:
- 月の岩は通常,ほとんど水を含まない.
- 月面から採取したサンプルの岩66095には,水分が異常に多く含まれている.
- 岩66095の水は,主に低温で放出されます.
研究 の 目的:
- 月岩66095.5の水分と同位体組成を特徴づけるために
- 月面のサンプルに含まれる水の起源を調査する.
- 月面の水の同位体シグネチャを地上の水とと比較するために.
主な方法:
- 水の放出温度を測定するための熱重力測定分析.
- 放出された水の同位体分析 (デルタDとデルタ{18) O)
- 炭素同位体分析 (デルタ) (13) C).
主要な成果:
- 月岩66095は140〜750ppmの水を含み,90%が690°C以下で放出されます.
- 低温水には,SMOWの1ミリあたり75~140のデルタD値があり,陸上の水と同じです.
- 高温水は,SMOW.の1ミリあたり -175±25のデルタDを持っています.
- delta(18) 1ミリあたり+5±1のO値のSMOWは,月のシリケートに似ているが,地上の生とは異なる.
結論:
- 岩66095の水の同位体組成は,それが単に地上の起源ではないことを示唆しています.
- 月面の水には,地上の水と区別がつかないデルタDがある可能性があるという証拠があります.
- この発見は,月の水の起源と進化の理解に重大な意味を持つ.
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