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恒星群の内部と外部にある惑星の頻度は同じです
Søren Meibom1, Guillermo Torres, Francois Fressin
1Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA. smeibom@cfa.harvard.edu
Nature
|June 28, 2013
まとめ
海王星に似た小さな惑星が,密集したNGC6811のオープンクラスターで発見された. この発見は,オープンクラスターの惑星の頻度と特徴が,フィールドスターの周りに存在する惑星と一致することを示唆しています.
科学分野:
- 天文学と天体物理学について
- エクソプラネット科学 エクソプラネット科学
背景:
- ほとんどの恒星と惑星は,開かれた星団で発生しますが,低い恒星密度で多くの星が散らばります.
- より古く,より密度の高い開いた星団は,太陽の誕生地と比較して明確な恒星環境を提供します.
- フィールドスターには800以上の海王星大小またはより小さな惑星が宿っており,オープンクラスターで発見されたガス巨星はわずか4つしかありません.
研究 の 目的:
- 密集した,古代のオープンクラスターの小さな惑星の存在と特性を調査する.
- オープンクラスターの惑星集団と,フィールドスターの周りに存在する惑星集団を比較する.
主な方法:
- 通過観測を利用して,太陽のような星の周りの惑星を検出しました.
- 10億年前のオープンクラスターNGC6811.1に注目した観測.
主要な成果:
- NGC6811.1の中で,海王星より小さな惑星が通過している2つの太陽のような星を検出しました.
- 密集したクラスター環境における小惑星の形成と生存を確認した.
結論:
- 小さな惑星は,密集した恒星群の中で形成され,存在し続けることができます.
- オープンクラスターの惑星の周波数と性質は,フィールドスターの周波数と性質に匹敵します.
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