Japan Geoscience Union Meeting 2018

Presentation information

[EE] Evening Poster

P (Space and Planetary Sciences) » P-PS Planetary Sciences

[P-PS04] Results from Akatsuki and advances in Venus science

Tue. May 22, 2018 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Takehiko Satoh(Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency), Takeshi Horinouchi(Faculty of Environmental Earth Science, Hokkaido University), Masaru Yamamoto(九州大学応用力学研究所, 共同), Kevin McGouldrick(University of Colorado Boulder)

[PPS04-P06] The global variation of Venus cloud observed by IR1 camera onboard AKATSUKI

*Seiko Takagi1 (1.Hokkaido University, Graduate School of Science)

Keywords:Venus, NearInfraRed, cloud

Venus is our nearest neighbor, and has a size very similar to the Earth’s. However, previous observations discovered an extremely dense (92 bar at the surface) and CO2-rich atmosphere, with H2SO4 thick clouds. The Venus cloud consists of H2SO4 main cloud deck at 47 – 70 km, with thinner hazes above and below. The upper haze on Venus lies above the main cloud surrounding the planet, ranging from the top of the cloud (70 km) up to as high as 90 km.
Near infrared (0.986 µm) dayside image of Venus has taken by solid state imaging (SSI) of the Galileo spacecraft (NASA). It appears almost flat, there are some small scale features with a contrast of 3 % [Belton et al., 1991]. In Takagi et al. (2011), it may be calculated that the source of the contrast of the order of 3 % in near infrared Venus dayside image is due to variation in the cloud optical thickness.
On December 7, 2015, AKATSUKI (JAXA) approached Venus and the Venus orbit insertion was successful. After the Venus orbit insertion, many 0.90 µm Venus dayside images were taken by the 1 µm near infrared camera (IR1) onboard AKATSUKI.
In this study, cloud optical thickness variation are investigated from 0.90 µm Venus dayside images taken by IR1 camera and radiative transfer calculation globally. Furthermore, we will examine Venus meteorological some change that contribute to cloud variation.