出口の探求:ボイジャー1号は,銀河とのヘリオスフィアの境界にある
S M Krimigis1, R B Decker, E C Roelof
1Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA. tom.krimigis@jhuapl.edu
まとめ
ヴォイジャー1号は,太陽エネルギー粒子の急激な減少と,銀河の宇宙線の上昇を,ヘリオシート境界で検出しました. この領域は,太陽のプラズマと星間媒体の間の移行を表しています.
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
- 天体物理学 天体物理学
背景:
- ヴォイジャー1号は太陽から123天文学単位離れた場所に位置し,ヘリオシェアと局所恒星間介質の間のインターフェース領域を横断しています.
- ヘリオシェアは熱した太陽プラズマで特徴づけられ,星間媒体は冷たい非太陽プラズマと銀河の磁場を含んでいる.
研究 の 目的:
- ヘリオシート境界のエネルギー有電荷粒子の測定を報告する.
- このインターフェイスで太陽と銀河の粒子強度の変化を分析するために.
主な方法:
- ボイジャー1号を用いたエネルギー有電荷粒子 (>40キロ電子ボルト) の測定.
- 異なる方向 (アジムタル,放射性,反放射性) での粒子の強度の変化の分析.
主要な成果:
- 2012年8月25日,太陽エネルギー粒子 >10(3) の因数による減少が観測されました.
- 銀河系宇宙線の9.3%の増加が同時に発生しました.
- 濃度の変化は,アジムタル方向,それから放射方向,反放射方向で連続的に観察されました.
結論:
- 予期せぬヘリオスフィアの"枯渇領域"がヘリオシート境界で特定されました.
- この領域は,太陽のプラズマと銀河の間の移行地帯を表している可能性があります.
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