火星のイオノスフィアに太陽フレアの影響
Michael Mendillo1, Paul Withers, David Hinson
1Center for Space Physics, Boston University, Boston, MA 02215, USA.
まとめ
太陽フレアは,火星のイオノスフィアを200%まで大幅に強化します. これらの効果は,紫外線に対する強化された柔らかいX線流によって引き起こされ,火星グローバルサーベイヤーによって観測されました.
科学分野:
- 惑星科学 惑星科学
- ソーラー物理学 ソーラー物理学
- 大気科学 大気科学
背景:
- 惑星の大気は,太陽のX線と紫外線 (UV) フレアに反応する.
- これらの太陽フレア効果の継続的で信頼性の高い測定は,主に地球に利用できます.
- 他の惑星におけるこれらの大気反応を理解することは,比較惑星学にとって極めて重要です.
研究 の 目的:
- 火星のイオノスフィアに対する太陽フレアの影響を報告し,分析する.
- 太陽フレアイベントによって引き起こされる火星のイオノスフィアの強化を定量化するために.
- 火星における太陽のフレア中の柔らかいX線と紫外線の相対的な貢献を調査する.
主な方法:
- マース・グローバル・サーベイヤー宇宙船のデータを活用した.
- 2001年4月の観測を分析し,特に太陽フレアイベントに焦点を当てました.
- フレア効果の高度依存性を理解するために大気モデリングを使用しました.
主要な成果:
- 太陽フレアイベント中に火星のイオノスフィアの200%の強化が観察されました.
- 柔らかいX線流の相対的な強化が,UV流の相対的な強化を大幅に上回ることを決定しました.
- 火星における太陽フレア強度とイオノスフィアの反応との関連を確立した.
結論:
- 太陽フレアは,火星のイオノスフィアに相当かつ測定可能な影響を及ぼします.
- 柔らかいX線は,紫外線よりも優位な役割を果たし,火星のイオノスフィアの強化を推進しています.
- 太陽と地球と太陽と火星の大気反応の比較研究が不可欠である.
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