恒星間水素の減速は,ヘリオスフィアのインターフェースで起こります
まとめ
地元の恒星間雲からの中性水素は,太陽系では減速します.
科学分野:
- 天文学と天体物理学について
- 星間媒介は,星間媒介である.
- ヘリオスフィア物理学 ヘリオスフィア物理学
背景:
- 高解像度の恒星スペクトルは,地元の恒星間雲からの吸収線を明らかにします.
- この雲は,太陽に対して26km/sの速度で移動し,星間風と一致しています.
- 以前の測定では,太陽系内の中性水素とヘリウムの速度が異なることが示されました.
研究 の 目的:
- 太陽系内の局所的な星間雲からの中性水素とヘリウムの速度を調査するために.
- 恒星間物質とヘリオスフィアのインターフェースの相互作用を決定する.
- 恒星間プラズマの密度とヘリオスフィアの衝撃の位置を制限するために.
主な方法:
- 近くの星からの高解像度スペクトルの分析により,星間雲の物質を研究する.
- ニュートラルヘリウム漂流測定のためのユリセス宇宙船からのデータを活用する.
- ハッブル宇宙望遠鏡の高解像度スペクトログラフを使用して,新しい水素放射線測定を行いました.
主要な成果:
- 地元の恒星間雲からの中性ヘリウムは,恒星間風と一致して,秒速26kmで漂流しています.
- 同じ雲からの中性水素は,20 km/sまで減速されます.
- この減速は,恒星間陽子との電荷交換が,ヘリオスフィアのインターフェイスで起きていることによるものである.
結論:
- 中性水素原子は,好ましくは,ヘリオスフィアのプラズマとの相互作用によって減速されます.
- 中性ヘリウムはプラズマの影響を受けず,選択的相互作用を示しています.
- 観測された減速は,恒星間プラズマ密度が0.060.10cm−3であることを意味し,太陽から100AU以内のヘリオスフィアの衝撃を意味する.
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