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1843年にエタ・カリーネが噴火した時の衝撃波です
1Astronomy Department, University of California, 601 Campbell Hall, Berkeley, California 94720-3411, USA. nathans@astro.berkeley.edu
Nature
|September 12, 2008
まとめ
観測により,19世紀のエタ・カリーナエの噴火で放出された物質が極めて高速で,その運動エネルギーは2倍になったことが明らかになった. これは,単なる恒星風ではなく,超新星のような強力な爆発が,輝く青色変数 (LBV) 噴火を起こす可能性があることを示唆しています.
科学分野:
- 天文学 天文学
- 天体物理学 天体物理学
- 恒星の進化について
背景:
- 巨大な恒星は,超新星の前には,明るい青色変数 (LBV) として激しい噴火を経験します.
- LBVの噴火の原因は不明である.
- 19世紀のエタ・カリーナの噴火は,太陽の12倍の質量を650km/sで噴出し,その運動エネルギーは1050ergでした.
研究 の 目的:
- エタ・カリーナエの19世紀の噴火からの噴出物の完全な分布と速度を調査するために.
- LBV噴火のエネルギー源と影響を決定する.
主な方法:
- 観測天文学は,観測による天文学である.
- エタ・カリーナ (eta Carinae) からの高速噴出物の分析
主要な成果:
- 19世紀のイベントで放出されたはるかに速い物質 (3,5006,000 km/s) の発見.
- この素早い物質は噴火の運動エネルギーを2倍にし,衝撃波を生み出します.
- エタ・カリーナの外殻は,今や低エネルギー超新星残骸に似ている.
結論:
- エタ・カリーナエのようなLBV噴火は,超新星と競合する深層の爆発によって推進される可能性があります.
- 脈動性ペアの不安定性は,そのような強力なLBVイベントを誘発する可能性があります.
- この発見は,類似の銀河外イベントの解釈を変えるかもしれない.
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