金星の質量,重力場,大気,イオノスフィアは,マリナー10二重周波無線システムによって測定されました
関連する実験動画
Updated: Jul 12, 2026

11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
まとめ
新金星のデータは,太陽と金星の質量比を408,523.9.9に精錬しています. 分析は,X帯信号の弱体化と以前のミッションよりも低い電子密度を持つ温度逆転とイオノスフィアの層を明らかにします.
科学分野:
- 惑星科学 惑星科学
- ラジオ科学 ラジオ科学
- 大気物理学 大気物理学
背景:
- 以前の研究では,マリナー2号とマリナー5号のデータを用いて,金星の質量比を測定した.
- 金星の重力場と大気構造を理解することは,惑星科学にとって極めて重要です.
研究 の 目的:
- ドップラー追跡データを用いて太陽と金星の質量比を決定する.
- 金星の重力場,特に慣性の主要な瞬間を調査するために.
- 金星の大気気温プロファイルとイオノスフィアを分析するために.
主な方法:
- 金星との遭遇時のドップラー追跡データ分析.
- 主要な慣性の瞬間における分数差の予備分析.
- ラジオ信号の衰弱 (XバンドとSバンド) の観測と分析.
- 電子の密度と構造を決定するためのイオノスフィアの探知.
主要な成果:
- 太陽と金星の質量比は408,523.9 ±1.2と決定されました.
- 金星の主要な慣性の瞬間における微分差異は,事前に10−4.4で制限されています.
- 標高56kmから63kmの間に4つの異なる温度逆転が確認されました.
- Xバンドの信号は,52kmで消え,有意な衰弱を経験しました.
- 夜側のイオノスフィアは2つの層 (ピーク密度は140/120 kmで104 e−/cm3) を示し,昼側のイオノスフィアは145 kmで3x105 e−/cm3のピークを示している.
- より高い高度での電子密度は,マリナー5の観測値より10倍低かった.
結論:
- 決定された質量比は,以前の測定値と一致しています.
- 高級重力場ハーモニクスの影響については,さらなる調査が必要である.
- 金星の大気は,複雑な熱構造と層層のイオノスフィアを示しています.
- ラジオ信号の伝播は大気条件によって影響を受け,イオノスフィアの密度は以前の発見とは異なる.
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