活発な地域の上での太陽風の速度を,遠隔ラジオ波観測を用いて決定する

J L Bougeret, J Fainberg, R G Stone

Science (New York, N.Y.)

|November 4, 1983

まとめ

科学者は現在,宇宙船の無線放射データを用いて太陽風の速度を測定することができます. この新しい技術は,太陽風の加速を観測するために,ラジオ波源を追跡し,理論的なモデルを確認します.

科学分野:

宇宙物理学宇宙物理学
ソーラー物理学ソーラー物理学
プラズマ物理学プラズマ物理学

背景:

太陽の上層大気から放出される電荷粒子の流れである太陽風は,宇宙天候に重要な役割を果たします.
太陽風の流れのダイナミクスを理解することは,宇宙天候の予測と太陽と地球の相互作用を理解するために不可欠です.
以前の方法では,特定の太陽風の塊が外へ膨張している時の速度を正確に測定する上で限界がありました.

研究の目的:

異なる太陽風の部分の速度を測定するための新しいテクニックを導入し,検証する.
太陽から離れていく太陽風の加速過程を調査する.
観測データを,太陽風の行動に関する既存の理論モデルと比較する.

主な方法:

国際太陽地球探査機3 (ISEE-3) のデータを活用した.
太陽活動地域と関連した太陽風地域から発生した放射能を分析した.
速度を推論するために,数日の間にわたるラジオ波源の表面的動きを追跡した.

主要な成果:

特定の太陽風の塊が,外向きに流れていく時の速度を測定しました.
理論的な予測と一致する太陽風加速の証拠を得ました.
太陽風のダイナミックな変化を追跡する新しい技術の能力を実証しました.

結論:

開発された技術は,太陽風の速度を in-situ で測定するための新しい能力を提供します.
観測の証拠は,太陽風加速の理論的モデルを裏付けている.
この方法は,将来の宇宙物理学研究と太陽風の研究に貴重なツールを提供します.

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