ウラノスの新しい塵帯:一環,二環,赤環,青環
Imke de Pater1, Heidi B Hammel, Seran G Gibbard
1Astronomy Department, 601 Campbell Hall, University of California, Berkeley, CA 94720, USA. imke@astron.berkeley.edu
Science (New York, N.Y.)
|April 8, 2006
まとめ
天王星の内輪 (R/2003 U 2) は赤色で,外輪 (R/2003 U 1) は異常な青色である. この青い色は,R/2003 U 1が,その月,マブとの衝突によって生成された可能性があることを示唆しています.
科学分野:
- 惑星科学は惑星科学である.
- 天文学 天文学
- リングシステム リングシステム
背景:
- 天王星には,最近発見された外環系があります.
- 惑星環の色と組成は,その起源と動態についての洞察を提供します.
研究 の 目的:
- 天王星の外環の近赤外線観測を,ハッブル宇宙望遠鏡のデータと比較するために.
- 天王星の環 R/2003 U 1 と R/2003 U 2 のスペクトル特性を特徴付け,その組成を推論する.
主な方法:
- ウラノスの環の近赤外線観測データの取得と分析.
- 現存するハッブル宇宙望遠鏡の結果とスペクトルデータの比較.
主要な成果:
- 内輪のR/2003 U2は,粉塵のリングの典型的な赤色のスペクトルサインを示しています.
- 外環R/2003 U 1は,鮮明に青い色を呈しており,知られている環系の中で珍しい特徴です.
- R/2003 U 1の青い色は,土星のE環に似ている.
結論:
- R/2003 U 2の赤い色は,土星のG環に似た組成を示唆しています.
- R/2003 U 1の異常な青い色は,ミクロン未満の大きさの塵が支配する組成を示唆し,その埋め込まれた月であるMab. Mab. への衝突によって潜在的に生成されます.
- Mabの周りの軌道動態は,微塵粒子の生存と分散を好み,リングの青い色に寄与する可能性があります.
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