天王星:マイクロ波スペクトルの変動性

S Gulkis, E T Olsen, M J Klein

Science (New York, N.Y.)

|July 29, 1983

まとめ

ラジオ観測により,天王星が発見された.

科学分野:

惑星科学は惑星科学である.
ラジオ天文学ラジオ天文学
大気科学大気科学

背景:

天王星のラジオ天文観測は,天王星のラジオ放射スペクトルの時間的な変化を示しています.
以前の研究では,Uranusの大気中のアンモニア蒸気の枯渇が示唆されていました.

研究の目的:

天王星のラジオ放射スペクトルの時間的な進化を調査するために.
ラジオ観測に基づいて天王星の大気組成と状態を決定する.

主な方法:

天王星のラジオ天文観測の分析.
異なる時期 (1965年から現在まで) のマイクロ波観測の比較.
大気不透明性プロファイルのモデリング.

主要な成果:

天王星のラジオ放射スペクトルは,時間とともに進化しています.
アンモニアのレベルは,時間や緯度によって減少しているようです.
現在の観測は,アンモニアではなく水蒸気が大気中の不透明性を支配していることを示唆しています.
重要な極-赤道熱グラデーションは起こりそうにない.

結論:

天王星の大気中のアンモニアの枯渇は,新しいデータによって支持されています.
放射性物質の放出に影響を与える大気組成は,おそらくアンモニアから水蒸気へと変化した.
これらの変化は,天王星の軌道位置と太陽に対する軸の傾きと相関しています.

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