概括
科学家在Abee石中发现了新的钻石. 这些钻石具有太阳系同位素组成,表明星云起源和低压合成,与星前星际钻石不同.
科学领域:
- 宇宙化学 宇宙化学
- 地质地质地质地质地质地
- 行星科学 行星科学
背景情况:
- 原始石含有太阳前和星云组成部分.
- 星际钻石 (Cdelta) 具有特定的同位素组成和高含量.
- 以前,钻石在石中的起源与冲击事件或特定类型的石有关.
研究的目的:
- 为了描述从蜜蜂恩斯塔石 (Abee enstatite chondrite) 中分离出来的钻石.
- 为了确定这些新发现的钻石的起源和形成条件.
- 为了将这些钻石与已知的太阳前和星云钻石种群进行比较.
主要方法:
- 采用已确定的度程序,将钻石从Abee enstatite chondrite中分离出来.
- 对碳 (delta) 13C, (delta) 15N和的同位素分析.
- 测量的度 (百万分之一的质量).
主要成果:
- 隔离了具有每毫升-2的三角形C值和低 (<50 ppm) 的钻石.
- 这些钻石呈现出典型的太阳系同位素组成的碳,和.
- 这些钻石大约100纳米大小,状,按质量构成Abee石的100ppm.
结论:
- 阿比钻石很可能来自星云,而不是太阳前.
- 它们在未被冲击的石中的存在表明了低压合成.
- 这一发现挑战了以前关于石中钻石形成的假设.
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