Japan Geoscience Union Meeting 2019

Presentation information

[E] Poster

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

[P-PS05] Recent advances of Venus science

Mon. May 27, 2019 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall8, 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(Research Institute for Applied Mechanics, Kyushu University), Kevin McGouldrick(University of Colorado Boulder)

[PPS05-P07] The global variation of Venus cloud obtained from IR1 camera onboard AKATSUKI

*Seiko Takagi1, Naomoto Iwagami, Yukihiro Takahashi1, Mitsuteru Sato1 (1.Hokkaido University, Graduate School of Science)

Keywords:Venus, cloud, near infrared

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 um) 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 and Iwagami. (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 um Venus dayside images were taken by the 1 um near infrared camera (IR1) onboard AKATSUKI. In this study, Venus cloud variations are investigated from 0.90 um Venus dayside images taken by IR1 camera globally. Further, meteorological some changes that contribute to cloud variation are examined in using radiative transfer calculation with high altitude cloud model obtained from Venus Express/SOIR observation. Furthermore, I will introduce observation plan with PIRKA telescope of Hokkaido University.