セドナのような天体で,周囲は80天文学単位
Chadwick A Trujillo1, Scott S Sheppard2
11] Gemini Observatory, 670 North A'ohoku Place, Hilo, Hawaii 96720, USA [2].
Nature
|March 28, 2014
まとめ
天文学者は,セドナのような2番目の天体2012 VP113を発見し,その周辺は80AU. この発見は,これらの物体がオート雲の内部に属している可能性を示唆し,他の太陽系の人口を上回る可能性があります.
科学分野:
- 天文学と天体物理学について
- 惑星科学は惑星科学である.
- 太陽系ダイナミクス 太陽系ダイナミクス
背景:
- 太陽系は岩石惑星,ガス巨星,氷のカイパーベルトの物体で構成されています.
- 惑星セドナ (Sedna) は,周辺日位76AUで,以前はユニークな存在でした.
- セドナの軌道は,外側のオート雲とのつながりを示唆していた.
研究 の 目的:
- セドナのような第二の物体の発見を報告するためです.
- この発見が太陽系形成モデルに及ぼす影響を調査する.
- 内部のオート雲の潜在的存在と構成を調査する.
主な方法:
- オブジェクトの検出と軌道分析 2012 VP113.3.
- 2012 VP113の軌道パラメータとセドナや他の太陽系天体の比較.
- セドナ型のオブジェクトの起源と分布を評価するための形成モデリング.
主要な成果:
- 2つ目のセドナ型天体である2012 VP113は,80AUの近日線で特定されました.
- セドナと2012 VP113は孤立していないので,似たようなオブジェクトの集団を示しています.
- これらのオブジェクトは,おそらく内部のオート雲のメンバーを表しています.
結論:
- 2012 VP113の発見は,内部のオート雲の存在を裏付けている.
- インナー・オート雲のオブジェクトは,太陽系で最も動的に安定した集団である可能性があります.
- 太陽系のこの新たに特定された領域を完全に特徴づけるためには,さらなる研究が必要である.
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