过境的太阳系外行星大气中的水蒸气
Giovanna Tinetti1, Alfred Vidal-Madjar, Mao-Chang Liang
1European Space Agency, Frascati 00044, Italy. gio@gps.caltech.edu
Nature
|July 13, 2007
概括
科学家在热木星HD 189733b的大气中检测到水蒸气. 这一发现是在行星过境期间观察到的,证实了水的存在.
科学领域:
- 外系行星科学 外系行星科学
- 大气物理学 大气物理学
- 红外天文学 红外天文学
背景情况:
- 水是热木星大气中的一个关键分子.
- 之前试图在这些行星上检测水的尝试产生了不确定的结果.
研究的目的:
- 为了分析最近对热木星HD 189733b在其过境期间的观测.
- 为了调查行星有效半径中波长依赖的变化的原因.
主要方法:
- 在行星过境期间分析红外线 (3.6,5.8和8微米) 和可见光观测.
- 将有效半径变化解释为吸收特征.
主要成果:
- 水蒸气吸收是红外波长观察到的有效半径变化最可能的解释.
- 在可见波长的更大有效半径可能是由于恒星的变化或云/雾.
- 之前没有检测到水是由于行星几乎同热的大气概况而解释的.
结论:
- 这项研究提供了令人信服的证据,表明HD 189733b.b.大气中的水蒸气存在.
- 了解大气组成对于描述系外行星至关重要.
- 大气概况显著影响分子物种的检测能力.
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