火星の磁気異常の上でのプラズマ加速は,火星の磁気異常の上でのプラズマ加速である
R Lundin1, D Winningham, S Barabash
1Swedish Institute of Space Physics, Box 812, S-98 128, Kiruna, Sweden.
Science (New York, N.Y.)
|February 18, 2006
まとめ
火星の明るいオーロラは,惑星の夜間大気中に加速するエネルギー粒子によって引き起こされます. これらの条件は,地球のオーロラと似ており,火星の地殻の磁場と関連しています.
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
- 大気科学 大気科学
背景:
- オーロラは,惑星の大気に衝突する電荷のある粒子から生じる.
- オーロラ光の明るさは,粒子を降ろすエネルギーの流れと相関しています.
- 火星は,その宇宙環境に影響を与える地殻の磁場を持っています.
研究 の 目的:
- 火星のナイトサイドの有電粒子加速過程を調査するために.
- 火星オーロラにおける粒子の落下エネルギーフックスを測定する.
- 火星のオーロラと地殻の磁力の関係を理解するために.
主な方法:
- マース・エクスプレス号の宇宙プラズマとエネルギー原子の分析器実験を活用した.
- 火星の高い夜辺の領域で加速電子とイオンを分析した.
- 粒子加速領域を火星の地殻磁化領域にマッピングした.
主要な成果:
- 火星の深夜高海域で加速電子とイオンを観測した.
- 地理的にこれらの領域をマッピングして,地殻の磁化に関連したインターフェース/割れ目の領域にしました.
- 1秒あたり1平方メートルあたり1〜50ミリワットまでのエネルギーフローを測定した.
結論:
- 火星の離散的なオーロラは,地殻の磁化領域の上の磁気流管の分岐でプラズマ加速と関連しています.
- 火星のオーロラの複雑なパターンは,多極磁場線によって形作られています.
- 観測された条件は,地球上の明るい分断的なオーロラを生成する条件に匹敵します.
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