土星の重力場,内部回転,内部構造について

John D Anderson¹, Gerald Schubert

¹121 South Wilson Avenue, Pasadena, CA 91106-3017, USA. jdandy@earthlink.net

Science (New York, N.Y.)

|September 8, 2007

まとめ

土星サターン

科学分野:

惑星科学惑星科学
天文学天文学
ガス巨人の研究

背景:

土星の内部回転周期は不明である.
以前の推定は,磁場と放射線データによって制限されていた.

研究の目的:

土星の正確な内部回転周期を決定するために.
土星の大気動力学と内部構造のモデルを精錬する.

主な方法:

カッシーニ宇宙船の重力データを活用した.
組み込まれたパイオニアとボイジャーの無線遮蔽と風データ.

主要な成果:

土星の自転周期を10時間32分35+/- 13秒と決定した.
以前に想定していたより低い赤道風速を示した.
観測された大気循環パターンは,木星のそれと似ています.

結論:

精巧な回転周期は,土星の内部構造の理解に影響を与える.
惑星の中心近くの分子から金属の水素への移行を示唆しています.

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