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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
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彗星67P/チュリュモフ・ゲラシメンコの集積塵
Mark S Bentley1, Roland Schmied1, Thurid Mannel1,2
1Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, 8042 Graz, Austria.
Nature
|September 2, 2016
まとめ
彗星の塵粒子はより小さな粒子の階層的集合体であり,初期の太陽の星雲状態の洞察を提供します. この構造は粒子の集積と彗星からの塵の放出に影響します
科学分野:
- 惑星科学
- 宇宙化学
- 天体物理学
背景:
- 彗星は太陽系形成の理解に不可欠な 初期の太陽雲の原始的な塵を保存しています
- 以前の研究では,間接的な観測に基づいて,彗星塵は毛細いアグロメラートで構成され,孔状の多孔な惑星間塵粒子に似ていると示唆されていました.
- 彗星塵の細粒子の構成要素は,以前のミッションで収集中に変更されました.
研究 の 目的:
- 彗星67P/チュリュモフ・ゲラシメンコからの微小な性質と集積構造を調査する.
- 彗星塵が階層的集積を示すかどうかを判断し,星間塵との性質を比較する.
- 彗星形成と塵の放出メカニズムにおける塵の集積の役割を理解する.
主な方法:
- 彗星探査の先端機器を用いた塵粒子のインサイト測定.
- 1マイクロメートルから数十マイクロメートルまでの塵粒子の地形画像.
- 粒子の形状,サイズ,伸びの分析
主要な成果:
- 彗星67P/チュリュモフ・ゲラシメンコからの彗星塵は,より小さい長方形の粒子の集合体である.
- 階層的な集積構造は,異なるサイズスケールで観察されました.
- 粉塵粒子の形状は多様で,コンパクトな単粒子や,コンドリート型の多孔型惑星間粉塵粒子のような多孔型積層を含んでいる.
- 測定した粒子の長さは 星間塵の推論値と一致する.
結論:
- 彗星の塵粒は,星間塵から生まれた彗星の構成要素を表すかもしれません.
- 階層的集積は彗星塵の集積の成長において重要なプロセスである.
- 塵の集積の階層構造は彗星核の張力に影響を与え,塵の放出を促進します.
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