最近のガス放出による月の活動
Peter H Schultz1, Matthew I Staid, Carlé M Pieters
1Brown University, Geological Sciences, Providence, Rhode Island 02912-1846, USA. peter_schultz@brown.edu
Nature
|November 10, 2006
まとめ
最近の月の表面の変化は,月からのガスの排出が進行していることを示唆しています.
科学分野:
- 月面地質学 月面地質学
- 惑星科学は惑星科学である.
- アストロジオロジー アストロジオロジー
背景:
- 広範囲にわたる月の火山活動は,約32億年前に停止した.
- 月面の進化は,過去10億年の間,衝突クレーター形成によって支配されていると考えられていた.
- 月は,月震や断層系を除いて,一般的に地質学的に不活性と考えられています.
研究 の 目的:
- インナ構造の内部の月面の最近の改変を調査する.
- インナ構造の特徴の年齢と形成過程を決定する.
- これらの発見が月面のガス排出と揮発性物質の含有量に及ぼす影響を調査する.
主な方法:
- クレーター統計と劣化の分析.
- トポグラフィック・レリーフの保存の評価.
- 規則石のスペクトル成熟度 (新鮮さ) の評価.
主要な成果:
- イナ構造の内部にある特徴は,近年の表面再生の証拠を示し,年齢は1000万年ほど若い.
- これらの特徴は,まだ活発に形成されている可能性があります.
- この発見は,最近,月面を形づくったのは衝突クレーターだけという仮定に異議を唱えている.
結論:
- 最近,月の内部からエピソード的にガスを放出することが,INA構造の観測された特徴を生み出した可能性が高い.
- このガスの放出は,過去の月面ミッションで検出された放射性ガスを説明するかもしれない.
- ガス組成を分析し,月の深層の揮発性物質を理解するためにさらなる監視が必要である.
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