航海士の画像で雲を追跡することによって得られた海王星の風速
まとめ
ヴォイジャー2号の画像は,海王星の恒常的な雲の特徴を明らかにし,その自転周期は15.8〜18.4時間です. 雲の上の風速は,太陽エネルギー投入の大きな違いにもかかわらず,金星から海王星まで類似しています.
科学分野:
- 惑星科学は惑星科学である.
- 大気ダイナミクス 大気ダイナミクス
- ネプテュンの研究 ネプテュンの研究
背景:
- ネプテュンの大気は,動的な雲の特徴を示しています.
- 以前の研究では,大気回転周期が変化していることが示されていた.
研究 の 目的:
- 海王星の雲の特徴の回転周期と風速を分析するために.
- 太陽系の内側と外側における大気動態を比較する.
主な方法:
- ボイジャー2号からの狭角カメラ画像の分析.
- 雲の特徴の回転周期の計算.
- 惑星の内部回転周期に相対する風速の計算.
主要な成果:
- ネプテュンの恒久的な雲の特徴を特定した.
- これらの特徴の回転周期は15.8時間から18.4時間です.
- 計算された雲の上風速は,東方向に20m/sから西方向に325m/sまで.
結論:
- 海王星の大気は,異なる回転周期を持つ複雑なダイナミクスを示しています.
- ネプテュンの雲の頂上にある風速は,太陽エネルギー投入の1000倍の違いにもかかわらず,金星の風速に匹敵します.
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