紫外線スペクトロメーターによる海王星とトリトンの観測
まとめ
海王星の上層大気は750ケルビンに達し,紫外線スペクトルは他のガス巨星と似ています. トリトンの大気は主に窒素で,表面圧力は14マイクロバーです.
科学分野:
- 惑星科学は惑星科学である.
- 大気物理学 大気物理学
- スペクトロスコーピーは,スペクトロスコーピーを用います.
背景:
- 外惑星の大気組成と熱構造を理解することは,比較惑星学にとって極めて重要です.
- ガス巨星に関する以前の観測は,海王星の大気特性を比較するための基礎を提供した.
研究 の 目的:
- 太陽遮蔽データを用いて海王星の気温と大気組成を決定する.
- ネプテュンの太陽が照らした大気の紫外線スペクトルを分析するために.
- ネプテュンの月であるトリトンの大気の性質を調査する.
主な方法:
- 大気温と組成を推論するための太陽遮蔽測定.
- 大気中の放射を分析するための紫外線および極紫外線スペクトロスコピー.
- トリトンの大気の特徴化のための空気光観測.
主要な成果:
- 海王星の上層大気温は750 +/- 150ケルビンと推定されています.
- ネプテュンの下層大気中のメタン,アセチレン,エタンの分布を決定した.
- 海王星の紫外線スペクトルは,木星,土星,天王星と同じような,Hライマンアルファと分子水素の放射によって支配されています.
- エクストリーム紫外線放射のスケールは,日中心距離の逆正方形である.
- トリトンの大気は主に分子窒素と微量メタンで,気温95+/- 5ケルビン,表面圧力約14マイクロバーと特定されました.
結論:
- 海王星の大気特性は,スペクトル放射の観点から,他の巨大惑星のそれと一致しています.
- ヴォイジャー号の観測は,太陽系外部の全域にわたるUV放射の一貫したスケーリングを提供します.
- トリトンは薄い窒素-メタンの大気を持っています.
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