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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
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星团内部和外部的行星的频率相同
Søren Meibom1, Guillermo Torres, Francois Fressin
1Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA. smeibom@cfa.harvard.edu
Nature
|June 28, 2013
概括
在密集的NGC6811开放星团中发现了类似海王星的小行星. 这一发现表明,开放星团中的行星的频率和特征与野外恒星周围的行星一致.
科学领域:
- 天文学和天体物理学
- 外系行星科学 外系行星科学
背景情况:
- 大多数恒星和行星都起源于开放的星团,但恒星密度低导致许多恒星消散.
- 与太阳的出生地相比,更老,更密集的开放星团提供了一个独特的恒星环境.
- 野外恒星拥有超过800颗海王星大小或更小的行星,与在开放星团中发现的仅有四颗气体巨星形成鲜明对比.
研究的目的:
- 为了调查密集的,古老的开放星团中小行星的存在和特征.
- 为了比较开放星团中的行星种群与在野外恒星周围发现的行星种群.
主要方法:
- 利用过境观测来检测围绕类似太阳恒星的行星.
- 专注于对10亿年前的开放星团NGC6811进行观测.
主要成果:
- 在NGC6811.11中检测到两颗类似太阳的恒星,由比海王星小的行星穿过.
- 证实了小行星在密集的星团环境中的形成和生存.
结论:
- 小行星可以在密集的恒星团中形成并持续存在.
- 开放星团中的行星频率和属性与野星相似.
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