太陽とヘリオスフィアは,太陽の最大値に達する.
E J Smith1, R G Marsden, A Balogh
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
Science (New York, N.Y.)
|November 15, 2003
まとめ
ユリセスのデータは,太陽の磁場が,その回転軸にほぼ垂直であることを示しています. これはヘリオスフィアに影響を与え,太陽風と粒子を地球全体に誘導し,すべての緯度で宇宙線を減少させます.
科学分野:
- 宇宙物理学 宇宙物理学
- ヘリオフィジックス ヘリオフィジックス
- ソーラー物理学 ソーラー物理学
背景:
- ヘリオスフィアの構造とダイナミクスは,宇宙天候を理解するために極めて重要です.
- 太陽の最大値は,太陽とその環境を観察するためのユニークな条件を提示します.
- ヘリオスフィアの磁場方向の以前のモデルは,限られた観測に基づいていた.
研究 の 目的:
- 太陽の最大期間の3次元ヘリオスフィアを特徴づけるために.
- ヘリオスフィアの磁場の起源と方向を調査する.
- 太陽風,エネルギー粒子,宇宙線の緯度分布を理解する.
主な方法:
- ユリセス宇宙船のデータを活用して.
- 赤道から極地まで,幅広い太陽緯度における観測を分析する.
- 磁場測定を太陽風の性質とエネルギー粒子データと相関させる.
主要な成果:
- ヘリオスフィアの磁場二極は,太陽の回転軸にほぼ垂直な方向を向いている.
- 低緯度の磁場,太陽風,エネルギー粒子は,全ヘリオスフィアの緯度まで広がる.
- すべての緯度において,宇宙線流の対称的な減少が観察されました.
- 高緯度の急速な太陽風と極の冠状孔は,同時に姿を消し,再現する.
結論:
- 太陽の磁場幾何学は,地球上のヘリオスフィアの条件に大きく影響する.
- 低緯度の現象は,ヘリオスフィア全体を埋める上で支配的な役割を果たしています.
- これらのダイナミクスを理解することは,宇宙天候現象とその影響を予測する鍵です.
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