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恒星の活動と明るさの変動:太陽の歴史を垣間見る
Science (New York, N.Y.)
|January 5, 1990
まとめ
太陽の輝度は,磁気活動のサイクルによって変化し,古い恒星と似ています. 若い恒星は逆の行動を示し,時間の経過とともに太陽の明るさの変動が変化していることを示しています.
科学分野:
- 太陽物理 太陽物理学
- 星の天体物理学 星の天体物理学
- 天文学 (astronomy) 天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは
背景:
- 合計太陽照射量 (TSI) は,太陽の11年間の磁気活動サイクルに関連した変動を示しています.
- 以前の衛星ミッション (ソーラー・マキシマム・ミッション,ニンバス7) は,TISの変動に関する初期データを提供した.
研究 の 目的:
- 太陽の磁気活動と太陽の全照射量との間の観測された関係を確認し,拡張する.
- 異なる年齢の恒星と磁気活動のレベルにおける恒星の明るさの変動を調査する.
- 太陽の明るさの変動の長期的な進化を理解するために.
主な方法:
- ソーラー・マキシマム・ミッションとニンブス7衛星からの放射測定値の分析.
- ローウェル天文台とマウント・ウィルソン天文台で行われた恒星観測.
- 太陽や他の恒星の磁気活動レベルと明るさの変化の比較.
主要な成果:
- 太陽の合計太陽放射線量は,その11年間の磁気サイクルによって変化することを確認しました.
- 古い太陽のような星は,磁気活動の増加に伴い,一般的に明るくなることが観察されました.
- 若い恒星は,磁気活動の増加に伴い,弱くなる傾向があることが判明しました.
結論:
- 若い恒星と古い恒星の対照的な明るさの振る舞いは,恒星の生涯にわたる太陽の変動性を支配する基本的な物理的メカニズムのシフトを示唆しています.
- 太陽の現在の振る舞いは,古い恒星を代表するもので,進化の過程で輝度調節プロセスが変化することを意味しています.
- この研究は,太陽を含む恒星の長期的な安定性と進化の洞察を提供します.
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