パレオマグネティズム パレオマグネティズム セマルコナ隕石で記録された太陽星雲の磁場
Roger R Fu1, Benjamin P Weiss2, Eduardo A Lima2
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA. rogerfu@mit.edu.
Science (New York, N.Y.)
|November 15, 2014
まとめ
初期の惑星の形成には,強い磁場が関係していたのかもしれません. 隕石の分析により,54 ± 21 マイクロテスラスの星雲磁場が明らかになり,惑星形成の重要な理論が支持されています.
科学分野:
- 惑星科学は惑星科学である.
- 天体物理学 天体物理学
- 地質物理学 地質物理学とは地質物理学です.
背景:
- 磁場は惑星の形成に不可欠であると仮定されています.
- それらは物質の蓄積と初期の固体の形成を調節する可能性があります.
- 以前の研究では,これらの古代の磁場の強度に関する実験データがなかった.
研究 の 目的:
- 惑星形成の初期段階における磁場の強さを実験的に決定する.
- コンドルル形成のメカニズムと原惑星円盤のダイナミクスに関する仮説を検証する.
主な方法:
- セマルコナ隕石から採取されたオリヴィン系コンドルールの分析.
- コンドルルに記録された古代の磁場の強度を判断するための古磁気分析.
主要な成果:
- セマルコナ隕石からのホンドルルは,54 ± 21 マイクロテスラスの nebular フィールドで磁化されました.
- この磁場強さは,星雲ショックや小惑星衝突などの形成メカニズムをサポートしています.
- 地球上の惑星形成地域における背景磁場は,推定5~54マイクロテスラであった.
結論:
- 測定された磁場強度は,原惑星円盤における質量および角運動量輸送を説明するのに十分である.
- これらの発見は,惑星形成における磁場の役割に関する重要な実験的制約を提供します.
- この結果は,特定のコンドルール形成モデルを他のモデルよりも好み,初期の太陽系についての理解を洗練しています.
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