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Updated: May 31, 2026

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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
創世記太陽風サンプルによって示されたように,太陽系における15N-貧乏な同位体組成です
B Marty1, M Chaussidon, R C Wiens
1Centre de Recherches Pétrographiques et Géochimiques (CRPG), Nancy Université, Vandoeuvre-lès-Nancy, France. bmarty@crpg.cnrs-nancy.fr
まとめ
創世記ミッションは,太陽風の窒素が窒素-15 (15N) で枯渇していることを発見しました. これは,初期の太陽系における極度の同位体変動を明らかにし,他の場所で発見された15Nが乏しい物質を説明します.
科学分野:
- 宇宙化学 (コスモケミストリー)
- 惑星科学は惑星科学である.
- 天体物理学 天体物理学
背景:
- 太陽系における窒素の同位体組成は十分に理解されていない.
- 太陽風は,太陽と太陽前星雲のサンプルを提供します.
- ジェネシスミッションは,太陽風の元素および同位体組成を分析することを目的とした.
研究 の 目的:
- 太陽風の窒素における窒素-15/窒素-14 (15N/14N) の比率を決定する.
- 太陽系における窒素同位体変動の起源を調査する.
- 原太陽雲の窒素同位体組成を特徴づけるために.
主な方法:
- ジェネシス太陽風コンセントレーターの標的材料に埋め込まれた窒素同位体の分析.
- 精密な同位素比測定のための質量スペクトロメトリ.
主要な成果:
- 太陽風の窒素は,2.18 ± 0.02 × 10−3.3の15N/14N比を示しています.
- この比率は,地球の大気と比較して15Nで約40%低い.
- 原太陽雲の15N/14N比は2.27 ± 0.03 × 10−3と決定され,太陽系で知られている中で最も低い値である.
結論:
- 初期の太陽系は極度の窒素同位体異質性を有していた.
- 15Nが枯渇した太陽風は,他の太陽系材料に見られる15Nが枯渇したコンポーネントを構成しています.
- この発見は,誕生した太陽系の化学的進化に関する重要な洞察を提供します.
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