ジョビアの磁気尾のエネルギー粒子
R L McNutt1, D K Haggerty, M E Hill
1Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA. ralph.mcnutt@jhuapl.edu
Science (New York, N.Y.)
|October 13, 2007
まとめ
"ニュー・ホライゾンズ"宇宙船は木星を調査した.
科学分野:
- 惑星科学は惑星科学である.
- 宇宙物理学 宇宙物理学
- 天体物理学 天体物理学
背景:
- 木星には強力な磁場があり,太陽風と相互作用しています.
- この相互作用は巨大な磁気尾を形成し,木星の宇宙環境の重要な構成要素である.
- 磁気尾のダイナミクスを理解することは,木星系の流出過程の鍵です.
研究 の 目的:
- 木星の磁気尾の構造と動態を調査するために.
- マグネトーテール内のエネルギー粒子集団を分析する.
- 遠方の磁気尾にプラズマの行動と潜在的注入機構を特定する.
主な方法:
- ニュー・ホライゾンズ宇宙船によるイン・シトゥ測定.
- 木星の磁気尾の全長を横断し,木星の半径2500を超えました.
- エネルギー粒子速度の分散,アニゾトロピー,および組成の分析.
主要な成果:
- マグネトーテール全体で高温で多種多様なエネルギー粒子集団が観察されました.
- 深尾 (RJ >500) の3日~周期的な変動が検出され,木星近くでの観測に似ています.
- 識別されたシグネチャは,プラズマの流出と,尾の近く領域 (200-400 RJ) での潜在的な磁気再接続イベントと一致しています.
結論:
- 木星の磁気尾は少なくとも1655 RJ.まで相関性を維持しています.
- プラズマのストリーミングと注入のイベントは,磁気尾の内部で発生します.
- マグネトテイルは,木星系から外へ物質を誘導する上で重要な役割を果たします.
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