MESSENGERは,水星の磁気尾の極端な負荷と負荷の観測を行った
James A Slavin1, Brian J Anderson, Daniel N Baker
1Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA. james.a.slavin@nasa.gov
Science (New York, N.Y.)
|July 22, 2010
まとめ
メルキュール メルキュール メルキュール メルキュール
科学分野:
- 宇宙科学,惑星科学,およびプラズマ物理学.
背景:
- 水星の磁気圏は極度の磁気尾の負荷を呈しており,地球の磁気荷を大幅に上回っている.
- 地上のサブストームは,磁気尾の負荷によって駆動され,水星の磁気圏のダイナミクスの比較モデルを提供します.
研究 の 目的:
- 水星の磁気圏のサブストームの間,磁気尾の負荷の特徴と影響を調査する.
- 水星のサブストームの強度と時間スケールを,地球上で観測されたものと比較するために.
主な方法:
- メッセンジャー号の第3回水星の横断飛行から得た磁場データの分析.
- 観測されたテールフィールドの強化を,地上のサブストームデータと磁気圏モデルと比較.
主要な成果:
- 観測された磁場は,2〜3分の間隔で2〜3.5の因数で水星の尾に増加します.
- 水星の尾の負荷は,地球の約10倍強烈です.
- テイルフィールド強化の持続時間は,ダンギサイクルと相関しており,それがサブストームの時間スケールを支配することを示唆しています.
結論:
- 水星のサブストームは,観測されたエネルギー粒子加速が欠如しているにもかかわらず,地球のそれよりも著しく強烈です.
- ダンギーのサイクルで説明されているプラズマ循環は,水星の磁気圏におけるサブストームの持続時間を決定する重要な要因です.
関連する概念動画
01:27Magnetic Fields
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01:19Magnetic Field Lines
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Magnetic field lines follow several hard-and-fast rules:
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01:23Magnetic Field due to Moving Charges
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01:28Magnetostatic Boundary Conditions
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01:18Magnetic Flux
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