原惑星の隙間を通るガスの流れ
Simon Casassus1, Gerrit van der Plas, M Sebastian Perez
1Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile. scasassus@u.uchile.cl
Nature
|January 4, 2013
まとめ
観測により,若い恒星HD 142527の原惑星円盤の隙間からガスが流れていくことが明らかになり,惑星の形成が活発に恒星増殖を養っていることを示しています. このガスの流れは,星を維持するために極めて重要です.
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.
背景:
- 惑星形成モデルは,原惑星円盤の隙間を予測しています.
- 若い恒星HD 142527は,内部ディスク,大きなギャップ,外部のディスクが破壊されている.
研究 の 目的:
- HD 142527 原惑星円盤の隙間内のガスダイナミクスを調査するために.
- ガス流が観測された高い恒星増殖率を維持できるかどうかを判断する.
主な方法:
- ディスクの構造をマップするための赤外線観測.
- 分子ガスの組成と分布を分析するためのラジオ観測.
- 隙間内の拡散したCOと密度の高いHCO+ガスの分析.
主要な成果:
- 隙間内では分散したCOガスが検出された.
- 隙間横断フィラメントに沿って観察されたより濃厚なHCO+ガス.
- 推定ガスフロー率は,年間7x10^-9から2x10^-7の太陽質量である.
結論:
- 観測されたガスの流れは,恒星の高収縮率を維持するのに十分である.
- 原惑星の体は,外側から内側へガスを運ぶ可能性が高い.
- これは,恒星の活動に影響を与える惑星の形成が進行している証拠を提供します.
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