星間多循環性アロマティック炭化水素と惑星間塵の粒子や隕石に含まれる炭素
Science (New York, N.Y.)
|July 3, 1987
まとめ
惑星間塵の粒子や隕石には,ポリサイクル芳香炭化水素 (PAH) に似た炭酸性物質が含まれています. これらの発見は,宇宙でのPAHは,恒星塵の殻で形成され,最小限の恒星間変異を経験することを示唆しています.
科学分野:
- アストロケミストリー アストロケミストリー
- 宇宙化学 (コスモケミストリー)
- 惑星科学は惑星科学である.
背景:
- 惑星間塵粒子 (IDP) と隕石は地球外物質である.
- ポリサイクル芳香炭化水素 (PAHs) は,宇宙で発見された有機分子です.
- PAHsは,星間赤外線放射の特徴に責任があると仮定されています.
研究 の 目的:
- IDPと隕石における炭酸性物質の存在と起源を調査する.
- IDPや隕石のスペクトル特性を星間PAHシグネチャーと比較する.
- PAHsの潜在的地球外起源を探求する.
主な方法:
- IDPと隕石のラーマンスペクトロスコーピー.
- 光発光スペクトルの分析.
- 炭酸相におけるデウテリウムと水素の比率の測定.
主要な成果:
- IDPや隕石のラーマンスペクトルは,星間PAH放射に似た特徴を示しています.
- いくつかのIDPで観察された赤い光発光は,PAHに起因する天文観測と一致しています.
- IDPと隕石は,地上のサンプルよりも高度のデウテリウムと水素の比率を示しており,UV照射された星間PAHと一致しています.
結論:
- IDPや隕石の炭酸性物質は,星間PAHと類似している.
- これらの発見は,PAHが周周塵殻で形成されるという仮説を裏付けている.
- この物質は,塵の粒子や隕石に組み込まれる前に,星間空間で限られた変化を経験する可能性がある.
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