在原行星盘中识别硫化铁颗粒
L P Keller1, S Hony, J P Bradley
1Mail Code SR, NASA Johnson Space Center, Houston, Texas 77058, USA. lindsay.p.keller@jsc.nasa.gov
Nature
|May 10, 2002
概括
在年轻的恒星天体中发现了以前未被发现的硫化铁 (FeS) 颗粒. 这一发现解决了太空中枯竭硫的奥秘,证实了FeS是宇宙尘埃的关键组成部分.
科学领域:
- 天文学和天体物理学
- 太空化学 太空化学
- 行星科学 行星科学
背景情况:
- 硫在冷,密集的分子云中显著耗尽,这表明它存在于这些环境中的固体颗粒形式.
- 硫化铁 (FeS) 是彗星尘埃中的主要硫种,但对FeS缺乏直接的天文证据,这对理解硫的宇宙丰富性构成了挑战.
研究的目的:
- 为了识别天文来源中缺失的硫的形式.
- 调查环恒星尘埃中硫化铁 (FeS) 颗粒的存在和重要性.
主要方法:
- 采集和分析来自原始石和行星间尘埃的硫化铁 (FeS) 和 pyrrhotite ([Fe,Ni](1-x) S颗粒的实验室红外光谱.
- 实验室光谱与年轻恒星物体的红外光谱的比较.
主要成果:
- 实验室光谱显示出一个独特的FeS特征,以23.5微米为中心.
- 在年轻的恒星物体中观察到类似的光谱特征,以前被误认为是FeO.
- 天文线强度与气相硫耗尽和典型的银河硫/比率保持一致.
结论:
- 硫化铁 (FeS) 颗粒被确定为环恒星尘埃中至关重要的,以前未被识别的成分.
- 在天文源中检测到FeS解决了恒星间介质中耗尽气体硫的长期问题.
- 这一发现证实了银河系中预期的硫的丰富性.
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