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彗星67Pの2つの独立で原始的な殻
Matteo Massironi1,2, Emanuele Simioni3, Francesco Marzari4
1Dipartimento di Geoscienze, University of Padova, via G. Gradenigo 6, 35131 Padova, Italy.
Nature
|September 30, 2015
まとめ
彗星67P/チュリュモフ・ゲラシメンコ
科学分野:
- 惑星科学
- 彗星科学
- 太陽系形成
背景:
- 彗星核の形成因子はほとんど不明である.
- 彗星67P/チュリュモフ・ゲラシメンコの双葉形は,核融合や発掘の可能性を示唆している.
- 彗星核の構造を理解することは 太陽系の初期進化の鍵です
研究 の 目的:
- 彗星67P/チュリュモフ・ゲラシメンコの双葉核の構造組成と形成を調査する.
- 原子核が単一の物体なのか 複数の物体の集まりなのかを 判断する.
- 初期の太陽系における 原始的な過程を 解明するために
主な方法:
- 彗星67Pのメジャーロブとマイナーロブの両方の層状の分析.
- 個々の葉と核全体の重力ベクトルの計算.
- 重力ベクトルと観測された層の向きを比較する.
主要な成果:
- 彗星67Pのメジャーロブには,マイナーロブとは異なる層状の覆いがある.
- 重力ベクトルは,分葉を独立して分析すると,層に垂直に並べられます.
- 核は"オニオンのような"層化を示し,異なるオブジェクトの合併前の形成を示しています.
結論:
- 彗星67P/チュリュモフ・ゲラシメンコは,2つの異なる彗星から形成された集積体である.
- これらの彗星は太陽系初期に 穏やかで低速の衝突を経験しました
- 葉の構造の類似性は,独立した彗星小惑星の比較可能な原始分層の蓄積過程を示唆する.
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