メッセンジャーX線スペクトロメトリーによる水星の表面の主要な元素の組成
Larry R Nittler1, Richard D Starr, Shoshana Z Weider
1Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015, USA. lnittler@ciw.edu
Science (New York, N.Y.)
|October 1, 2011
まとめ
メルキュール メルキュール メルキュール メルキュール メルキュール
科学分野:
- 惑星科学は惑星科学である.
- 地質化学 地質化学
- アストロケミストリー アストロケミストリー
背景:
- 水星の表面の構成はほとんど不明である.
- 水星の組成を理解することで,地上の惑星の形成に関する洞察が得られます.
研究 の 目的:
- X線光データを用いて水星の表面構成を分析する.
- 水星の組成を他の地上の惑星と比較し,その形成の歴史を制限するために.
主な方法:
- MESSENGER宇宙船によって得られたX線光スペクトルの分析.
- 元素の比率 (Mg/Si,Al/Si,Ca/Si,Fe,S,Ti) を惑星の地殻や隕石物質のモデルと比較する.
主要な成果:
- 水銀の表面はMg/Siの比率が高く,Al/SiとCa/Siの比率が低く,フェルダスパートに富んだ月の地殻とは違います.
- 硫黄の豊富さは,地球や月よりも少なくとも10倍高い.
- 低表面の鉄とチタンの豊富さは,表面反射率の主要な要因として不透明な酸化物をサポートしません.
結論:
- 水銀の表面の組成は,高度に還元された物質から形成されたことを示唆し,おそらくエンスタタイトコンドライトまたは無水彗星塵である.
- 惑星の地殻は,月の地殻のようにフェルドスパートに富んでいない.
- 組成は,水銀の低反射率のために不透明な酸化物に依存するモデルに挑戦しています.
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