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Updated: Jul 7, 2026

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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
彗星81P/ワイルド2の原子核とジェットのモデリングは,スターダスト遭遇データに基づいています
Zdenek Sekanina1, Donald E Brownlee, Thanasis E Economou
1Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA. zs@sek.jpl.nasa.gov
まとめ
スターダスト宇宙船のデータは,彗星の核ジェットが特定の明るいスポットと斜面から発生し,均一ではないことを明らかにしています. これらのジェットは薄いエジェクトシートを形成し,回転する核の局所的な放出源を示唆しています.
科学分野:
- * 惑星科学 (惑星科学)
- * 彗星科学について
- * 宇宙ミッション分析
背景:
- *彗星核の性質を理解することは,太陽系形成理論にとって極めて重要です.
- * 彗星のジェットは,物質の放出と活動の主なメカニズムです.
研究 の 目的:
- * スターダスト宇宙船のデータを用いて核の性質とジェット活動の解釈.
- * 彗星のジェットとエジェクトの起源と特徴を特定する.
主な方法:
- *スターダスト宇宙船の画像と塵監視システムのデータを分析した.
- * 観測された20個のジェットを三角化し,その起源を決定した.
- * ジェット源と核のトポグラフィー,表面の特徴との相関.
主要な成果:
- * 核の暗黒側から2つのジェットが放出されていることが観察されました.
- *16個のジェットは,太陽の上昇が予測を上回る斜面から発生した.
- *マヨ低谷にある5つを含む7つの噴射源は,明るい表面のスポットと一致しました.
- * 塵の衝突データによると,宇宙船は薄くて密度の高い噴出物シートを横切った.
結論:
- * 彗星噴射は,原子核の特定の局所的な源,しばしば明るいスポットから発生します.
- * 観測された噴出物分布は,これらの源からの排出コーンモデルと一致しています.
- *核の地形と太陽光照明は,ジェット形成と活動において重要な役割を果たします.
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