パラサイト母体の固化によるコンベクションによる長寿磁気
James F J Bryson1, Claire I O Nichols1, Julia Herrero-Albillos2
1Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK.
Nature
|January 23, 2015
まとめ
初期の惑星系には,以前の理論とは対照的に,長寿命の磁場があった. この研究は,隕石の中核の固化によって誘発される磁気活動を明らかにし,太陽系初期に広範囲に広がり,永続的な磁気時代があった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.
- 地質物理学 地質物理学とは地質物理学です.
- 宇宙化学 (コスモケミストリー)
背景:
- 隕石からの古磁気データは,初期の太陽系惑星体が磁場を生成したことを示しています.
- 現在のモデルでは,熱で駆動されたコンベクションが示唆されており,短期間の磁気活動を示唆しています.
研究 の 目的:
- 初期の惑星系における磁場発生の持続時間と誘導因子を調査する.
- パラサイト母体の古磁気史を再構築する.
主な方法:
- イミラックとエスケルパラサイト隕石のナノ磁気画像.
- 磁場特性と冷却速度を決定するために,古磁気記録の分析.
主要な成果:
- パラサイトの親体には長寿の磁気活動史が確認された.
- この研究では,核の固化に関連した磁場の衰退と最終的なシャットダウンを捉えました.
結論:
- 漸進的な内核固化によって引き起こされる磁気活動は,観測されたデータと一致しています.
- 固化によるコンベクションが,太陽系初期の天体の遅い,長続きした,激しい磁気活動の原因になった可能性が高い.
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