在太阳系早期可能在现场形成石纳米钻石
Z R Dai1, J P Bradley, D J Joswiak
1School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
Nature
|July 12, 2002
概括
太阳前的纳米钻石,曾经被认为在石和彗星中丰富,在行星间尘埃中令人惊地罕见. 这挑战了它们的起源,表明它们可能在太阳系内部形成,而不仅仅是围绕着其他恒星.
科学领域:
- 宇宙化学 宇宙化学
- 行星科学 行星科学
- 天文学 天文学
背景情况:
- 太阳前颗粒提供了对恒星形成和太阳系早期演变的见解.
- 来自石的纳米钻石被认为是最丰富的太阳前颗粒.
研究的目的:
- 为了研究行星间尘埃颗粒 (IDP) 中纳米钻石的丰富性.
- 重新评估 presolar纳米钻石的起源和分布.
主要方法:
- 对脆弱的,富含碳的行星间尘埃颗粒进行分析.
- 在IDP中纳米钻石丰富度与石和彗星样本的比较.
主要成果:
- 在分析的IDP中,纳米钻石不存在或极度耗尽.
- 这与预期纳米钻石应该在原始的,外太阳系物质如彗星中丰富的预期相矛盾.
结论:
- 一些纳米钻石可能在太阳系内部形成,而不仅仅是太阳前.
- 另一个选择是,前太阳纳米钻石分布可能会随着日中心距离的减少而减少,这表明我们对早期太阳系运输的理解不完全.
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