カイパーベルトのオブジェクト (50000) Quaoarの水晶の水氷
1Institute for Astronomy, 2680 Woodlawn Drive, Honolulu, Hawaii 96822, USA. jewitt@hawaii.edu
Nature
|December 14, 2004
まとめ
カイパーベルトのオブジェクトであるクオアは,水晶の水氷とアンモニア水合物の兆候を示しており,最近表面が再現されたことを示唆しています. これは,原始的な太陽系天体でダイナミックなプロセスが活発であることを示している.
科学分野:
- 惑星科学 惑星科学
- 天文学 天文学
- 太陽系探査 太陽系探査について
背景:
- 海王星の向こうにあるカイパーベルトには,太陽系の原始的な物質が隠されている.
- ほとんどのカイパーベルトオブジェクト (KBO) は,詳細な構成分析には弱すぎます.
- カイパーベルトの表面温度は極めて低い (約 50 K) でした.
研究 の 目的:
- 大型のカイパーベルトオブジェクト (50000) Quaoar.の表面構成を調査するために.
- カイパーベルトの氷の保存と潜在的な変化を理解するために.
主な方法:
- (50000) Quaoar.の近赤外線観測結果
- 表面材料を特定するための光譜分析.
主要な成果:
- Quaoarの表面に結晶の水氷が検出されました.
- アンモニア水合物の識別.
- 証拠によると,氷は少なくとも110Kまで加熱されている.
結論:
- 結晶の氷とアンモニア水合物の存在は,クォーアが最近地表に浮上したことを示している.
- 可能性のある再表面化メカニズムには,衝撃被曝または冷凍火山活動が含まれます.
- これらの発見は,低温にもかかわらず,KBOにおける活発な地質学的プロセスを示唆しています.
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