メッセンジャー号の初飛行時の水星の磁場構造
Brian J Anderson1, Mario H Acuña, Haje Korth
1Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA. brian.anderson@jhuapl.edu
Science (New York, N.Y.)
|July 5, 2008
まとめ
MESSENGER宇宙船は,水星の赤道付近の磁場強度が,マリナー10の発見と似ていることを確認した. 分析により,このフィールドは純粋な中心二極体である可能性が示唆されているが,より高次元の構成要素も可能である.
科学分野:
- 惑星科学は惑星科学である.
- マグネトヒドロダイナミクス
- 宇宙物理学 宇宙物理学
背景:
- 水星は,その内部ダイナモを理解するために不可欠な,地球規模の磁場を持っています.
- マリナー10号による以前の測定は,水星の赤道磁場に関する初期データを提供した.
研究 の 目的:
- メッセンジャーの最初の水星のフライバイからの磁場測定を紹介します.
- 水星の赤道付近の磁場を特徴付け,以前の観測と比較する.
主な方法:
- MESSENGER宇宙船が初飛行中に収集した磁場データの分析.
- 中心二極と多極の解法を用いて磁場をモデル化する.
主要な成果:
- MESSENGERの測定は,Mariner 10の赤道データと10%の範囲で一致するフィールド強さを示しています.
- 二極解は,230−290 nT·RM3 の間の南向きの惑星モーメントを示し,自転軸から 5°−12° の傾きを示します.
- マルチポール解は,二極フィールドの22%から52%の範囲の非二極貢献を示します.
結論:
- 観測された磁場は,純粋な中心の二極体と,有意な高級成分を持つ磁場の両方と一致しています.
- マグネトパウズ,尾流,およびプラズマ圧力効果は,観測されたフィールドの複雑さに寄与する可能性があります.
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