オート雲彗星の質量破壊
Harold F Levison1, Alessandro Morbidelli, Luke Dones
1Southwest Research Institute, 1050 Walnut Street, Suite 426, Boulder, CO 80302, USA. hal@gort.boulder.swri.edu
Science (New York, N.Y.)
|June 22, 2002
まとめ
ほとんどのオート雲彗星は,太陽系の内部に到達する前に物理的に破壊されます. ダイナミックモデルは,観測されたものより100倍も多くの休眠彗星を予測しており,その旅の間に彗星が著しく破壊されたことを示している.
科学分野:
- 天文学と天体物理学について
- 太陽系科学 太陽系科学
- 彗星科学 彗星科学
背景:
- オート雲は,太陽系を囲むと信じられている氷の体の理論的な殻です.
- オーート雲から発生した彗星は,ほぼ同極彗星を含む,動的に分類されています.
- これらの彗星の集団と進化を理解することは,太陽系形成モデルにとって極めて重要です.
研究 の 目的:
- 太陽系内の休眠状態の,ほぼ同位圏のオート雲彗星の数を計算する.
- 理論的な彗星集団と観測データとの不一致を調和させるため.
- 彗星が内部へ移動する過程で発生する物理的過程を研究する.
主な方法:
- 軌道分布モデルと彗星発見の統計モデルを組み合わせた.
- モデル予測と既知の休眠彗星の観測を比較した.
- 動的モデルを用いて彗星の進化と生存率をシミュレートした.
主要な成果:
- ダイナミックモデルでは,現在観測されているものより約100倍多くの眠っているほぼ同位型彗星を予測しています.
- この不一致は,彗星の物質が著しく失われていることを示唆している.
- 彗星の大部分は,オート雲から離れる途中,物理的に破壊されなければなりません.
結論:
- オート雲から発生した彗星の大多数は,太陽系内部の内側への旅を生き残らない.
- 物理的な破壊は,オート雲彗星の進化において支配的なプロセスである.
- 現在のモデルは,より堅牢な彗星破壊機構を組み込む必要があります.
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