Scattering Properties of the Venusian Clouds Observed by the UV Imager on board Akatsuki

作者：Lee Y J^*; Yamazaki A; Imamura T; Yamada M; Watanabe S; Sato T M; Ogohara K; Hashimoto G L; Murakami S

来源：Astronomical Journal, 2017, 154(1): 44.

DOI：10.3847/1538-3881/aa78a5

• planets and satellites: atmospheres
• ultraviolet: planetary systems

We analyze the albedo of Venus obtained from the UV Imager on board Akatsuki. A relative global mean albedo over phase angle is used in this study, and we confirm the glory feature at 283 and 365. nm in the data acquired in 2016 May. We successfully simulate the observation using a radiative transfer model. Our results show that cloud aerosols of r(eff) = 1.26 mu m and v(eff) = 0.076 (mode 2) can explain the glory, consistent with a property of aerosols previously suggested by using the Venus Monitoring Camera on board Venus Express. We find that SO2 and the unknown UV absorber are necessary factors to explain the decreasing trend of the observed relative albedo at phase angles larger than 10(omicron). We suggest a range of possible SO2 abundance from 80 to 400. ppbv at the cloud top level, depending on atmospheric conditions assumed.

• 出版日期2017-7