Venus looks different from day to night across wavelengths: morphology from Akatsuki multispectral images.

Autor: Limaye SS; 1Space Science and Engineering Center, University of Wisconsin, Madison, WI 53706 USA., Watanabe S; 2Space Information Center, Hokkaido Information University, Ebetsu, Hokkaido 069-8585 Japan., Yamazaki A; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Yamada M; 4Planetary Exploration Research Center, Chiba Institute of Technology, 2-17-1, Tsudanuma, Narashino, Chiba 275-0016 Japan., Satoh T; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Sato TM; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Nakamura M; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Taguchi M; 5College of Science, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo, 171-8501 Japan., Fukuhara T; 5College of Science, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo, 171-8501 Japan., Imamura T; 6Department of Complexity Science and Engineering, Graduate School of Frontier Sciences, The University of Tokyo, Kiban-tou 4H7, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 Japan., Kouyama T; 7Artificial Intelligence Research Center, National Institute of Advanced Industrial Science and Technology, Tokyo, Japan., Lee YJ; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan.; 8Present Address: Department of Complexity Science and Engineering, Graduate School of Frontier Sciences, The University of Tokyo, Kiban-tou 4E5, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 Japan., Horinouchi T; 9Faculty of Environmental Earth Science, Hokkaido University, N10W5, Sapporo, Hokkaido 060-0810 Japan., Peralta J; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Iwagami N; School of Commerce, Senshu University, 2-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8580 Japan., Hashimoto GL; 11Department of Earth Sciences, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama, 700-8530 Japan., Takagi S; 12Tokai University, Research and Information Center, 4-1-1 Kitakaname, Hiratsuka-shi, Kanagawa 259-1292 Japan., Ohtsuki S; School of Commerce, Senshu University, 2-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8580 Japan., Murakami SY; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Yamamoto Y; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Ogohara K; 13School of Engineering, University of Shiga Prefecture, Hikone, Japan., Ando H; 14Faculty of Science, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto-City, 603-8555 Japan., Sugiyama KI; 15Department of Information Engineering, National Institute of Technology, Matsue College, 14-4 Nishi-Ikuma, Matsue, Shimane 690-8518 Japan., Ishii N; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Abe T; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Hirose C; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Suzuki M; 3Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Chuo-ku, Sagamihara, 252-5210 Japan., Hirata N; 16ARC-Space, CAIST, The University of Aizu, 90 Kami-Iawase, Tsuruga, Ikki-machi, Aizu-Wakamatsu, Fukushima 965-8580 Japan., Young EF; 17Southwest Research Institute, 1050 Walnut St., Suite 300, Boulder, CO 80302 USA., Ocampo AC; 18NASA Headquarters, 300 E Street SW, Washington, DC 20546 USA.
Jazyk: angličtina
Zdroj: Earth, planets, and space : EPS [Earth Planets Space] 2018; Vol. 70 (1), pp. 24. Date of Electronic Publication: 2018 Feb 12.
DOI: 10.1186/s40623-018-0789-5
Abstrakt: Since insertion into orbit on December 7, 2015, the Akatsuki orbiter has returned global images of Venus from its four imaging cameras at eleven discrete wavelengths from ultraviolet (283 and 365 nm) and near infrared (0.9-2.3 µm), to the thermal infrared (8-12 µm) from a near-equatorial orbit. The Venus Express and Pioneer Venus Orbiter missions have also monitored the planet for long periods but from polar or near-polar orbits. The wavelength coverage and views of the planet also differ for all three missions. In reflected light, the images reveal features seen near the cloud tops (~ 70 km altitude), whereas in the near-infrared images of the nightside, features seen are at mid- to lower cloud levels (~ 48-60 km altitude). The dayside cloud cover imaged at the ultraviolet wavelengths shows morphologies similar to what was observed from Mariner 10, Pioneer Venus, Galileo, Venus Express and MESSENGER. The daytime images at 0.9 and 2.02 µm also reveal some interesting features which bear similarity to the ultraviolet images. The nighttime images at 1.74, 2.26 and 2.32 µm and at 8-12 µm reveal features not seen before and show new details of the nightside including narrow wavy ribbons, curved string-like features, long-scale waves, long dark streaks, isolated bright spots, sharp boundaries and even mesoscale vortices. Some features previously seen such as circum-equatorial belts (CEBs) and occasional areal brightenings at ultraviolet (seen in Venus Express observations) of the cloud cover at ultraviolet wavelengths have not been observed thus far. Evidence for the hemispheric vortex organization of the global circulation can be seen at all wavelengths on the day- and nightsides. Akatsuki images reveal new and puzzling morphology of the complex nightside cloud cover. The cloud morphologies provide some clues to the processes occurring in the atmosphere and are thus, a key diagnostic tool when quantitative dynamical analysis is not feasible due to insufficient information.
Competing Interests: There are no financial and non-financial competing interests.
(© The Author(s) 2018.)
Databáze: MEDLINE
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