惑星間および恒星間塵が木星の磁気圏によって捕捉される
J E Colwell1, M Horányi, E Grün
1Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309-0392, USA. colwell@casper.colorado.edu
Science (New York, N.Y.)
|April 29, 1998
まとめ
惑星間塵粒は木星の周りに薄いリングを形成する. 大きさは0.5〜1.5マイクロメートルで,木星の磁気圏内で特定の軌道特性を有しています.
科学分野:
- 惑星科学は惑星科学である.
- 天体物理学 天体物理学
- 宇宙物理学 宇宙物理学
背景:
- 木星の磁気圏は,太陽風と惑星のプロセスによって影響を受ける複雑な環境です.
- 惑星間および恒星間からの外来粉塵粒子は,惑星の磁気圏に侵入することができます.
研究 の 目的:
- 木星の磁気圏内の外来塵の拡散リングの形成と特性を調査する.
- これらの塵粒のサイズ分布と軌道動態を分析するために.
主な方法:
- 木星の磁気圏内の塵粒の性質を分析した.
- 観測データと数値軌道統合の比較.
- ガリレオの塵探知器によるin situ検出のデータを利用する.
主要な成果:
- 塵粒 (0.51.5ミクロメートル) で構成された,外来物質の検出可能な拡散した薄いリングが特定されました.
- 粒子は 4:1 の比率で逆行軌道と進行軌道を示し,特定の半大軸,離心点,傾きがある.
- 測定された塵粒の割合は,軌道のモデルから予測された密度と一致しています.
結論:
- 観測された塵の輪は,木星の磁気圏に惑星間および恒星間塵が侵入していることに一致しています.
- 塵粒の大きさと軌道特性は,in situ測定を裏付けている.
- 数学的モデルによって,木星の磁気圏内の外来塵の密度が正確に予測されます.
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