The nighttime ozone and sulfur dioxide distributions were analyzed using the entire Spectroscopy for the Investigation of the Characteristics of the Atmosphere of Venus (SPICAV) UV/Venus Express stellar occultation data set. After the discovery of an ozone layer at 100 km in the mesosphere reported by Montmessin, Bertaux, et al. (2011, https://doi.org/10.1016/j.icarus.2011.08.010), 132 other detections were made during the entire 8 years long observing period of the SPICAV UV instrument. In the rare detections, the peak abundances of O₃ accumulating in the mesosphere are observed with densities from 10⁷ to 10⁸ molecules⋅cm⁻³ at 85–110 km. The ozone layer is estimated to vary from 1 to 30 ppbv at 85–95 km while at 95–105 km the volume mixing ratio is expected within an interval from 6 to 120 ppbv. Below 93 km, a puzzling decrease of mixing ratio is observed towards midnight at 30°N. Our work also provides an improved sequel to the analysis of the sulfur dioxide survey previously made in the upper mesosphere by Belyaev, Evdokimova, et al. (2017, https://doi.org/10.1016/j.icarus.2017.05.002). On average, the SO₂ content is found to remain constant throughout the vertical profile at a value of around 135 ± 21 ppbv between 85 and 100 km. Rapid and large variations prevent to conclude firmly on any time or space pattern of SO₂.

中文翻译：

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通过SPICAV UV恒星掩星推断金星中层夜间臭氧和二氧化硫的时空分布。

使用整个光谱仪分析了夜间臭氧和二氧化硫的分布，以研究金星大气（SPICAV）的紫外线/金星快速恒星掩星数据集的特征。Montmessin报道，Bertaux等在中层大气中发现了100 km的臭氧层。（2011年，https：//doi.org/10.1016/j.icarus.2011.08.010），在SPICAV UV仪器的整个8年观察期内，共进行了132次其他检测。在极少见的检测中，以10 ⁷到10 ⁸分子· ^{cm -3的}密度观察到在中层层中积累的O ₃的峰丰度。在85–110公里处。臭氧层在85–95 km范围内估计为1到30 ppbv，而在95–105 km范围内，预计体积混合比在6到120 ppbv之间。在93 km以下，在30°N午夜时可观察到令人困惑的混合比降低。我们的工作还为Belyaev，Evdokimova等人先前在中层中层进行的二氧化硫调查分析提供了改进的后遗症。（2017年，https：//doi.org/10.1016/j.icarus.2017.05.002）。平均而言，发现在整个垂直剖面中，SO ₂含量在85至100 km之间保持恒定，约为135±21 ppbv。快速而大的变化会阻止在SO _2的任何时间或空间模式上得出可靠的结论。