孔德鲁和孔德里特的形成条件
C M O'D Alexander1, J N Grossman, D S Ebel
1Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015, USA.
概括
孔德鲁,太阳系早期的水滴,可能是在密集的,自我引力区域形成的. 这解释了它们的含量,并将孔德鲁形成与行星小发展联系起来.
科学领域:
- 行星科学 行星科学
- 宇宙化学 宇宙化学
- 太阳系早期的进化过程
背景情况:
- 圆柱体是毫米大小的酸盐球体,在原始石 (圆柱体) 中大量存在.
- 它们的形成涉及太阳系内部早期的能量过程,但条件仍然不清楚.
- 圆柱体形成是一个关键的过程,它将尘埃与行星状物联系起来.
研究的目的:
- 为了研究孔德鲁的形成条件.
- 为了解释chondrules的化学特性,特别是挥发性元素的丰度.
- 为了将圆柱体形成与行星小行星形成联系起来.
主要方法:
- 在chondrules中的丰度的分析.
- 模拟圆柱体形成环境的建模.
- 模型预测与chondrule化学成分的比较.
主要成果:
- 挥发性元素在体形成过程中表现出持续的丰富性.
- 恒定的在形成区域中需要高的固体密度,这表明自我引力环境.
- 这个模型解释了其他的孔德鲁尔化学特征.
结论:
- 宏德鲁形成很可能发生在自我引力,密集的区域.
- 宏德鲁形成和小行星形成很可能是相互关联的过程.
- 了解圆柱体的形成,可以了解太阳系积聚的早期阶段.
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