火星探査機パトファインダーのデータが,地上の惑星の蓄積史に及ぼす影響
1Geophysical Laboratory and the Center for High Pressure Research, Carnegie Institution of Washington, 5251 Broad Branch Road NW, Washington, DC 20015, USA.
Science (New York, N.Y.)
|September 22, 1998
まとめ
C1コンドライトの組成を想定した惑星増殖モデルは,火星には不十分である. 火星 火星 火星 火星
科学分野:
- 惑星科学は惑星科学である.
- 地質物理学 地質物理学とは地質物理学です.
- 宇宙化学 (コスモケミストリー)
背景:
- 地球上の惑星の蓄積モデルでは,大部分の構成にはC1炭酸性コンドライトが用いられます.
- これらのモデルでは,C1コンドライトに似た非揮発性元素の豊富度比を想定しています.
- この仮定は,惑星形成の研究で広く使用されています.
研究 の 目的:
- 地上惑星形成のためのC1コンドライトベースの蓄積モデルの十分性を調査する.
- 火星の慣性因子の瞬間が惑星の組成に及ぼす影響を分析する.
- 将来の惑星増殖モデルへの調整を提案する.
主な方法:
- 火星の慣性因子の瞬間の分析.
- 観測された火星データとC1コンドライト組成モデルからの予測の比較.
- 鉄 (Fe) 含量とFe/Si比率の評価について
主要な成果:
- 火星の慣性ファクターの瞬間は,大質量惑星のC1 Fe/Si比率と矛盾しています.
- 観測された火星のFe含量とFe/Si比はC1コンドライト値から逸脱する.
- C1コンドライトモデルは,火星の形成と構成を説明するのに不十分です.
結論:
- C1コンドライトの蓄積モデルは,火星の形成を説明するのに不十分です.
- 陸上の惑星の間の大量Fe/Si比の変動も考慮しなければならない.
- 将来のモデルは,惑星の組成に対してより微妙なアプローチを必要とします.
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