ヴォイジャー1号がヘリオシート枯渇領域に入ったときの磁場観測
L F Burlaga1, N F Ness, E C Stone
1NASA-Goddard Space Flight Center, Greenbelt, MD 20771, USA. lburlagahsp@verizon.net
Science (New York, N.Y.)
|July 2, 2013
まとめ
ヴォイジャー1号は,予期せぬ磁場増加と粒子減少を検知し,恒星間空間ではなく,ヘリオシート枯渇領域に入ったことを示した.
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
- 惑星科学は惑星科学である.
背景:
- ヴォイジャー1号 (V1) は,ヘリオスフィアの外側を探査し,ヘリオスフィアの重要なデータを提供してきました.
- ヘリオスフィアと恒星間介質の境界を理解することは,ヘリオ物理学の鍵です.
研究 の 目的:
- ボイジャー1からの磁場と粒子データを分析して,新たに発見された地域の性質を特定する.
- 探査機ボイジャー1号が恒星間介質,またはヘリオシート内の他の領域に入ってきたかどうかを判断するために.
主な方法:
- ボイジャー1号からの磁場強度と方向測定の分析.
- 磁場データとエネルギー粒子 (原子粒子1個につき0.5メガ電子ボルト) の数値との相関.
主要な成果:
- ボイジャー1号は,2012年210日~238日の間に5回,予期せぬ境界線を越えました.
- 磁場強度は ~0.2 から ~0.4 nanotesla に倍増し,上昇し続けました.
- より強い磁場は,エネルギー粒子の数値が著しく低いと相関する.
結論:
- 観測された現象は,ボイジャー1号がヘリオシート枯渇領域に入ったことを示しています.
- この地域は,磁場が強化され,粒子の流れが減少していることが特徴であり,星間介質とは異なる.
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