太陽風の磁場は,木星の塵の軌道を曲げている
1SN3, NASA Johnson Space Center, Houston, TX 77058, USA. Hamilton, Department of Astronomy, University. zook@snmail.jsc.nasa.gov
Science (New York, N.Y.)
|November 29, 1996
まとめ
ユリセス宇宙船は木星から11の塵の流れを検出しました. これらの宇宙塵粒は,太陽風の磁場の影響で,以前に観測されたよりも速く,より軽量でした.
科学分野:
- 宇宙物理学 宇宙物理学
- 惑星科学は惑星科学である.
- 宇宙塵の研究研究
背景:
- "ユリセス"宇宙船の宇宙塵探知器は,1991年9月から1992年10月までの間にこの現象を観測した.
- 宇宙塵に関する以前の研究は,ベースラインの質量と速度の範囲を確立しました.
研究 の 目的:
- 木星系から発生した塵の流れを分析するために.
- 塵粒軌道に太陽風の磁場力の影響を調査するために.
- これらの塵の流れの質量と速度の特性を決定する.
主な方法:
- ユリセス宇宙船の宇宙塵探知器からのオンボード測定を用いた.
- 宇宙船によって記録された磁場データを分析した.
- 塵の流れの接近方向を調べました.
主要な成果:
- 木星系から発する塵の 11 つの明確な短い爆発,またはストリームを記録しました.
- 粉塵粒の質量が約10~18gであることを確認しました.
- 測定された塵粒の速度は,秒速200キロを超える.
- 観測されたこれらの質量と速度は,以前の報告と著しく異なっており,質量が約1000倍少なく,速度が5〜10倍速い.
結論:
- 木星系からの宇宙塵の流れは,以前に記録されたものよりも著しく高い速度と低質量を示しています.
- 太陽風の磁場力は,これらの塵粒の軌道を形作る上で重要な役割を果たします.
- これらの発見は,太陽系内の塵の動力学と組成に関する新しい洞察を提供します.
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