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Updated: Jul 11, 2026

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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
金星:新しいマイクロ波測定では,大気中の水蒸気がないことが示されています
まとめ
受動的な無線観測により,金星の下層大気圏では水蒸気は検出されなかった. この発見は,以前の測定に異議を唱え,水蒸気は金星の雲や温室効果に大きな影響を与えない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.
- 大気科学 大気科学
- ラジオ天文学 ラジオ天文学
背景:
- ベネラ宇宙探査機のデータを含む以前の研究では,金星の下層大気圏に水蒸気が有意に存在していることが示唆されました.
- 金星の大気組成を理解することは,気候モデリングと比較惑星学にとって極めて重要です.
研究 の 目的:
- 金星の下層大気圏における水蒸気の存在と豊富さを,無線観測を用いて調査する.
- 異なる観測方法間の水蒸気測定の不一致を調和させるため.
主な方法:
- 1センチメートルの波長近くの金星の円盤温度スペクトルの測定.
- 1.35センチメートルの水蒸気共鳴で暗くなった金星の端のインターフェロメトリック測定.
主要な成果:
- 金星の下層大気圏では水蒸気の証拠は見つかりませんでした.
- 水蒸気の混合比の上限値は2x10−3と定められた.
- この上限値は,ヴェネラ宇宙探査機が報告した量より大幅に低い.
結論:
- 水蒸気の少ない量は,それが金星で濃い雲を形成できないことを示唆しています.
- 測定された水蒸気濃度が,金星の温室効果に大きく寄与しているとは考えられません.
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