小惑星セレスの形状によって明らかになった,小惑星セレスの差別化
P C Thomas1, J Wm Parker, L A McFadden
1Center for Radiophysics and Space Research, Cornell University, Ithaca, New York 14853, USA. thomas@baritone.astro.cornell.edu
Nature
|September 9, 2005
まとめ
かつて均質と考えられていた矮惑星セレスは,分化を示す証拠を示しています. その形状は岩石の核と氷のマントルを示唆し,内部構造に関する以前の仮定に異議を唱える.
科学分野:
- 惑星科学は惑星科学である.
- 小惑星研究研究.
- 太陽系形成 太陽系形成について
背景:
- 小惑星帯は,太陽系の歴史の初期に形成され,その形成の記録を保存しています.
- 4 Vestaのようないくつかの小惑星は,熱的に進化し,層状の構造に微分化しています.
- 最大の小惑星であるセレスは,低密度とスペクトルの特徴のため,均質であると考えられていた.
研究 の 目的:
- 矮惑星のセレスの内部構造と微分を調査する.
- 新しい形状と滑らかさのデータに基づいて,セレスの推定された均質性を再評価する.
主な方法:
- セレスの形状と表面の滑らかさの分析.
- 観察された特徴を,差異化され,均質な体のモデルと比較する.
主要な成果:
- サーレスは,重力的にリラックスした物体を示す形状と滑らかさを示しています.
- その形状は,均質な体で予想されるよりも平らな形であり,内部差異化を示唆しています.
- データは,中心の質量濃度,おそらく岩石の核を持つモデルをサポートしています.
結論:
- セレスは,以前の仮定に反して,差別化を経験しました.
- その内部構造は,水氷に富んだマントルで覆われた岩石のコアから成る可能性があります.
- セレスは,初期の太陽系プロセスと惑星の進化を理解するための重要な物体です.
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