局所的な恒星間塵の流れが,太陽放射線の圧力によって歪む
M Landgraf1, K Augustsson, E Grün
1NASA Johnson Space Center, Mailcode SN2, Houston, TX 77058, USA. mlandgra@esoc.esa.de
Science (New York, N.Y.)
|December 22, 1999
まとめ
恒星間塵粒は,太陽放射線の圧力により,2〜4AUの間では少なく見られる. 太陽の重力の1.4-1.8倍のこの圧力は,シリケートと有機耐火性粒子を影響する.
科学分野:
- * 惑星科学と天体物理学
- * 宇宙塵のダイナミクス
背景:
- *星間塵の組成と分布を理解することは,惑星の形成と進化にとって極めて重要です.
- * 過去の研究は,太陽系内の塵の集団の変動を示している.
研究 の 目的:
- * 恒星間塵粒の観測された欠乏を,2~4AUの太陽中心距離範囲で調査する.
- * 観測された塵粒の分布に起因する力を決定する.
主な方法:
- *宇宙船"ユリセス"と"ガリレオ"の塵探知器からのデータの分析.
- * 太陽放射線圧力と太陽重力の影響を様々な組成と大きさの塵粒にモデル化.
主要な成果:
- *星間塵粒 (質量1×10−17~3×10−16) の有意な欠乏が,2−4AUの領域と比べて,4AUを超える領域で検出されました.
- *太陽放射線の圧力は,太陽の重力の1.4~1.8倍で,これらの粒子を誘導する必要があります.
- *これらの比率は,天文学的シリケート,有機耐火材料,純粋なグラファイト粒 (0.2-0.4マイクロメートルの直径) の光学特性と一致しています.
結論:
- * 太陽放射線圧は,太陽系内部の恒星間塵の分布を形作る上で重要な役割を果たします.
- * 観測された塵の不足は,シリケート,有機,グラファイトの塵粒に作用する力と一致しています.
- *この発見は,塵の動力学と,惑星間環境における恒星放射線との相互作用についての洞察を提供します.
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