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超海王星物体クオアールの密集したリング,そのロシュ限界の外側
B E Morgado1,2,3, B Sicardy4, F Braga-Ribas5
1Federal University of Rio de Janeiro - Observatory of Valongo, Rio de Janeiro, Brazil. bmorgado@ov.ufrj.br.
Nature
|February 9, 2023
まとめ
天文学者は,従来のロシュの限界を遥かに超えた,超ネプテュンの天体クォーアーの周りのリングを発見しました. この発見は 弾性衝突とスピン軌道共鳴が 予期せぬ宇宙の領域に リングの存在を可能にすると示唆しています
科学分野:
- 惑星科学
- 天文学
- 天体物理学
背景:
- 惑星のリングは巨大惑星や チャリクロやハウメアのような小さな惑星の周りに存在します
- 以前は,すべての密度の高いリングは,潮力が衛星の形成を妨げているロシュの限界内で観察されました.
- ローシュの限界は,天体の重力によって保持されている天体が,第二の天体の潮力によって解体する理論的な境界線です.
研究 の 目的:
- 超海王星の天体 (50000) Quaoarの周りのリングシステムの発見と特徴を報告する.
- 古典的なロシュの限界を超えてリングの材料の生存を調査する.
- 小さな天体の周りに リングを閉じ込めるメカニズムを探る
主な方法:
- 超海王星天体 (50000) クアオアの観測.
- Quaoar's Rocheの限界に対するリングシステムの位置の分析
- 研究室での実験から得られたパラメータを用いた局所衝突シミュレーション.
主要な成果:
- 不均質な環が検出され,7.4クォーア半径で (50000) クォーアを回っている.
- このリングはクアオアの クラシック・ロシュ・リミットの外にあります
- リングはクアオールと1/3のスピン軌道共鳴に近い軌道に回っており,これはチャリクロとハウメア周辺のリングでも観察されている特徴です.
結論:
- 惑星の環の物質の生存の絶対的な境界ではないかもしれない.
- 弾性衝突は リングを親体から遠ざける上で 重要な役割を果たします
- スピン・オービットの共鳴は,小さな天体の周りのリングを閉じ込めるのに重要なようです.
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