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南極のドームCの上の天文学的観測条件は例外的なものです
Jon S Lawrence1, Michael C B Ashley, Andrei Tokovinin
1School of Physics, University of New South Wales, New South Wales 2052, Australia.
Nature
|September 17, 2004
まとめ
天文学的場所の選択は,望遠鏡の性能にとって極めて重要です. 南極のドームCは,大気の見渡し条件が非常に優れているので,地上望遠鏡は宇宙ミッションに匹敵する.
科学分野:
- 天文学 天文学
- 大気科学 大気科学
- 光学工学は,光学工学である.
背景:
- 優れた天文学的視力は,地上ベースの光学望遠鏡にとって非常に重要です.
- 最適な中緯度の場所は,0.5〜1.0弧秒の平均視力を持っています.
- 以前,南極ステーションでの南極観測では,視力低下 (1.8弧秒) が示されていた.
研究 の 目的:
- 南極高原のドームCにある大気の観測条件を調査するために.
- 次世代の天文観測所の場所としてのドームCの可能性を評価する.
主な方法:
- 冬の間,ドームC (南緯75度) で観測を行った.
- 光の経路に影響を与える大気屈折率の変動を分析した.
主要な成果:
- ドームCは,0.27アーチ秒の顕著な平均視力を示しています.
- ドームCの視覚条件は,25%の時間において0.15アーチ秒未満でした.
- この視覚は,中緯度のサイトよりも大幅に優れています.
結論:
- ドームCは,高度な天文観測所にとって理想的な,優れた大気の視界を提供します.
- ドームCの望遠鏡は,中緯度の場所にあるはるかに大きな望遠鏡の性能に匹敵し,またはそれを上回る可能性があります.
- ドームCのインターフェロメーターは,宇宙ミッションレベルのプロジェクトを可能にします.
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