HD 189733 b的HST/NICMOS透射光谱测量表明在系外行星大气中检测到甲烷（CH $_{4}$），这一直是一个重大争议的来源。这可能是迄今为止分析得最好的系外行星光谱数据集，不同的团队使用不同的方法，声称有证据既反驳又支持最初的发现。在这里，我们报告了对三个独立的已发布光谱进行统一光谱检索分析以及零假设检验的结果。基于贝叶斯模型比较，我们发现，三个光谱中的两个显示出强有力的证据（$\geq$ 3.6 $σ$）的分子特征的检测主要是由于水和甲烷，而第三个是一致的弱分子检测在2.2 $σ$水平。我们解释协议的光谱调制建立由以前的作者和大气检索结果在这里，作为确认的原始检测分子吸收剂在大气中的HD 189733 b。
英文摘要：
The HST/NICMOS transmission spectrum measurements of HD 189733b that suggest the detection of methane (CH$_{4}$) in an exoplanet atmosphere have been a source of significant controversy. With what is probably the best analyzed exoplanet spectroscopy data set to date, different teams, using different methods, have claimed evidence both contradicting and supporting the original findings. Here, we report results from a uniform spectral retrieval analysis of the three, independent, published spectra together with null hypothesis testing. Based on Bayesian model comparison, we find that two of the three spectra show strong evidence ($\geq$ 3.6$σ$) for the detection of molecular features mainly due to water and methane while the third is consistent with a weak molecular detection at the 2.2$σ$ level. We interpret the agreement in the spectral modulation established by previous authors and the atmospheric retrieval results presented here, as a confirmation of the original detection of molecular absorbers in the atmosphere of HD 189733b.
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