ヘール・ボップ彗星からの大量CO排出は,大太陽中心距離で発生しています
Nature
|March 14, 1996
まとめ
ヘイル・ボップ彗星は,水の氷の昇華ではなく,一酸化炭素 (CO) の放出による異常な輝きを示しています. このCOの亜熱化は,太陽から遠く離れたところでもその活動を推進しています.
科学分野:
- 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
- 彗星科学 彗星科学
- アストロケミストリー アストロケミストリー
背景:
- 彗星C/1995 O1 (ヘイル・ボップ) が7AUで発見されました.
- 彗星の輝きは,通常,揮発性氷の昇華によって引き起こされる塵粒の反射によるものです.
- 太陽の近くではよく見られる水氷の昇華は,ヘイル・ボップの現在の距離ではありそうにない.
研究 の 目的:
- ヘール・ボップ彗星の活動源を,大太陽中心距離で調査する.
- 彗星の観測された明るさと放出ガスの原因となる揮発性種を決定する.
主な方法:
- ヘール・ボップ彗星からのCO2排出量の検出.
- 他の揮発性生物種を探しましたが,見つかりませんでした.
主要な成果:
- ヘイル・ボップからのCO2排出量は,有意な排出ガスを示すレベルで確認されています.
- アクティビティは,水氷ではなく,一酸化炭素の亜鉛化に起因する.
結論:
- 炭素一酸化物 (CO) の昇華は,ヘイル・ボップ彗星の活動の主な原動力である.
- 将来の観測は,彗星が太陽に近づくにつれて,他の揮発性種の亜高化が始まっていることを明らかにするかもしれません.
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