金星の重力場: 予備分析

R J Phillips, W L Sjogren, E A Abbott

Science (New York, N.Y.)

|July 6, 1979

まとめ

ヴィーナス探査機パイオニアは,ヴィーナの重力場をマッピングし,異常を明らかにした. 北の高原は,浅い深さで補償を必要とし,地球と比較してユニークな惑星のプロセスを示唆しています.

科学分野:

惑星科学は惑星科学である.
地質物理学地質物理学とは地質物理学です.
グラビメトリー・グラビメトリー

背景:

金星の重力場は,金星の内部構造と地質学的過程を理解するために極めて重要です.
以前のミッションでは,高解像度の重力データが限られており,さらなる調査が必要でした.

研究の目的:

パイオニア・ヴェーナス号の宇宙船のデータを用いて,ヴィーナの視界の重力場をマッピングする.
重力の異常を調査するために,特に北部高原のような地形学に関連して.
金星の重力場特性を地球の特性と比較して,惑星の進化の違いを推測する.

主な方法:

視界線重力場マッピングは,ペリアプシスの近くにあるピオニア・ベーナス宇宙船の追跡を介して行われました.
特定の縦断 (294度から339度) の重力シグネチャーの分析.
長波長異常のフーリエ分解と,地球の重力データとのスペクトルの比較.

主要な成果:

重力シグネチャーの一貫した,体系的な変動は,観測された異常の現実性を確認します.
北の高原は重力シグネチャーを示さないため,高度の静止補償を意味する.
シミュレーションモデリングは,北部高原の補償深さが100km以下であることを示しています.
金星と地球は,平均重力スペクトルにおいて類似した総力を示しているが,調和の差異は,異なる動的プロセスまたは石層の振る舞いを示唆している.

結論:

金星の北の高原は,浅い深さで補償され,ユニークな地質学的プロセスを示しています.
比較スペクトル分析は,金星と地球の間の動的プロセスまたは石層の行動における根本的な違いを明らかにします.
高解像度の重力マッピングは,金星の内部構造と進化に関する重要な洞察を提供します.

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