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わずかな太陽風,または全くない太陽風は,太陽最小値で金星の大気圏に入ります
T L Zhang1, M Delva, W Baumjohann
1Space Research Institute, Austrian Academy of Sciences, A-8042 Graz, Austria. tielong.zhang@oeaw.ac.at
Nature
|November 30, 2007
まとめ
ヴィーナス (Venus) ヴィーナス (Venus) ヴィーナス (Venus) ヴィーナス (Venus) ヴィーナス (Venus) ヴィーナス (Venus) ヴィーナス (Venus) とは
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
- エアロノミーはエアロノミーです.
背景:
- 金星には地球規模の磁場がないため,太陽風が直接その大気と相互作用する.
- 誘導磁場は部分的な大気のシールドを提供しますが,太陽の最小値での有効性は不明です.
- 太陽風と金星の相互作用に関する現在の理解は,太陽の最大条件に基づいています.
研究 の 目的:
- 太陽最小期における金星の誘導磁気シールドの有効性を調査するために.
- 低太陽活動下で太陽風が金星の大気中に浸透する範囲を決定するために.
- 金星の大気進化に太陽風が与える影響を評価する.
主な方法:
- 磁場測定は,ヴィーナス・エクスプレス号によって収集されました.
- 分析は,プラズマ環境と金星の周りの弓の衝撃位置に焦点を当てた.
- データは低太陽活動条件下で収集されました.
主要な成果:
- 弓の衝撃は,磁気化されたイオノスフィアの完全な傾きと一致する位置で観察されました.
- わずかな太陽風が,太陽の最小値でも,金星のイオノスフィアに入り込むように見える.
- 誘導された磁場は,直接的な太陽風の影響から大気を効果的に保護します.
結論:
- 金星の大気は,太陽の最小期でも太陽風から著しく保護されています.
- 誘導された磁場は,地球をシールドする上で重要な役割を果たします.
- 大気進化に寄与する直接的な太陽風の吸収は最小限である.
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