MESSENGERから見た水星の重力場と内部構造
David E Smith1, Maria T Zuber, Roger J Phillips
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA.
Science (New York, N.Y.)
|March 23, 2012
まとめ
ラジオ追跡により,水星が発見された.
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.
- 天文学 天文学
背景:
- 水星の重力場と内部構造は,まだ完全に理解されていない.
- 以前のモデルには,詳細な重力異常データがなかった.
研究 の 目的:
- 水星の詳細な重力場モデルを開発する.
- 水星の内部密度分布と慣性の瞬間を制限するために.
主な方法:
- MESSENGER宇宙船からの無線追跡データの分析.
- 異常とマスクを組み込む重力場モデルの開発.
- 惑星の慣性モーメントと殻対惑星比の計算.
主要な成果:
- メルキュアの北半球で重力異常 (>100 mgal) を特定し,候補マスコンを含む.
- 決定 水星の北半球の地殻は,低緯度ではより厚く,極の近くではより薄い.
- 慣性のモメント (C/MR(2) = 0.353 ± 0.017) と固体外殻の比率 (C(m) /C = 0.452 ± 0.035) を計算した.
結論:
- 重力模型は,水星の異なる内部構造を支えている.
- 提案された密度モデルには,シリケート殻/マントル,鉄硫化物層,および鉄に富んだコア (液体の外側,おそらく固体の内側) が含まれる.
- これらの発見は,水星の形成と進化に関する重要な洞察を提供します.
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