クド・フジカワ彗星のプラズマ尾に観測された二重イオン化された炭素
Matthew S Povich1, John C Raymond, Geraint H Jones
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA. mpovich@cfa.harvard.edu
Science (New York, N.Y.)
|December 13, 2003
まとめ
彗星C/2002 X5 (Kudo-Fujikawa) は,独特の尾の組成を明らかにした. 高炭素イオンの豊富さは,塵の有機耐火性化合物からの起源を示唆し,彗星と太陽系物質を結びつける.
科学分野:
- 天文学 天文学
- 惑星科学は惑星科学である.
- 彗星科学 彗星科学
背景:
- 彗星C/2002 X5 (Kudo-Fujikawa) は,0.19AUで周日点に近づきました.
- 彗星の構成と起源に関する以前の研究.
研究 の 目的:
- 彗星C/2002 X5.5の構成を調査する.
- 彗星の尾の観測されたイオンの起源を決定する.
- 彗星と太陽系の形成とのつながりを強化する.
主な方法:
- 太陽と熱球天文台 (SOHO) の紫外線冠状図スペクトロメーター (UVCS) を用いた観測.
- 高解像度スペクトルの彗星画像の再構築.
- イオン量,特にC+とC2+の分析.
主要な成果:
- 準球形の中性水素雲を観測した.
- C+とC2+イオンの変数尾が検出され,接続が切断され再生されました.
- 高いC2+とC+ (水に比べて≥24%) を発見した.
結論:
- 高濃度のC+とC2+は,一酸化炭素の光解離によるものではない.
- 炭素イオンは,彗星塵内の耐火性有機化合物の原子炭素の蒸発と光イオン化から発生する可能性があります.
- この発見は,太陽系の原始物質の媒介者としての彗星の役割を強化している.
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