Ammonia in Jupiter’s Atmosphere: Spatial and Temporal Variations of the NH3 Absorption Bands at 645 and 787 Nm
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Based on the material of long-term spectrophotometric observations of Jupiter, we studied the weak absorption bands of ammonia at 645 and 878 nm, whose behavior had previously been little studied. A clearly expressed depression of ammonia absorption in the 787-nm band was found in the Northern Equatorial Belt (NEB) of Jupiter. In the Great Red Spot, this band also exhibits substantial weakening. The position of the depression in the NEB is similar to that of the enhanced brightness temperature detected in the observations of the millimeter-wave radio emission, which is considered to be a result of the reduced ammonia content in this belt. At the same time, the weakening of the 787-nm band in the Red Spot is most likely caused by the enhanced bulk density of clouds, which influences the formation of absorption bands in the multiple scattering by cloud particles. The brightness temperature in the Red Spot is relatively low, as seen from observations in the radio and thermal IR ranges. We studied the spatial and temporal variations of the 645- and 787-nm bands in five belts of Jupiter: the Equatorial Zone (EZ), both Equatorial Belts (SEB and NEB), and both Tropical Zones (STZ and NTZ). The observations covered the time interval from 2005 to 2015, i.e., almost a complete orbital period of Jupiter. These observations confirmed the systematic character of the depression of the 787-nm band in the NEB and the difference in the latitudinal variations of the 645- and 787-nm bands. The latter can be related to features of the vertical distribution of the cloud density, which has a different influence on bands of different intensity.
KeywordsJupiter atmosphere clouds Great Red Spot spectrophotometry ammonia molecular absorption thermal radiation
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- ALPO Japan—Jupiter, 2017. https://doi.org/alpo-j.asahikawamed.ac.jp/indexE.htm.
- Bjoraker, G.L., Wong, M.H., de Pater, I., and Ad’amkovics, M., Jupiter’s deep cloud structure revealed using Keck observations of spectrally resolved line shapes, Astrophys. J., 2015, vol. 810, no. 2, art. ID 122.Google Scholar
- Bowles, N., Private communication, 2009.Google Scholar
- Cox, A.N., Tejfel, V.G., and Tholen, D.J., Planets and satellites, in Astrophysical Quantities, New York: Springer-Verlag, 1999, pp. 293–313.Google Scholar
- Drossart, P., Roos-Serote, M., Encrenaz, Th., Lellouch, E., Baines, K.H., Carlson, R.W., Kamp, L.W., Calcutt, S., Irwin, P., Taylor, F.W., and Orton, G.S., The solar reflected component in Jupiter’s 5-micron spectra from NIMS/Galileo observations, J. Geophys. Res., 1998, vol. 103, pp. 23043–23050.ADSCrossRefGoogle Scholar
- Fletcher, L.N., Orton, G.S., Mousis, O., Yanamandra- Fisher, P., Parrish, P.D., Irwin, P.G.J., Edkins, E., Baines, K.H., Line, M.R., Vanzi, L., Fujiyoshi, T., and Fuse, T., Jupiter’s Great Red Spot: high-resolution thermal imaging from 1995 to 2008, Icarus, 2010, vol. 208, pp. 306–328.ADSCrossRefGoogle Scholar
- Mallama, A., The old and new meanings of cloud ‘belt’ and ‘zone’: a study of Jovian and Saturnian atmospheric banding based on Hubble Space Telescope images, arXiv 1410.3337v3 [astro-ph.EP].Google Scholar
- Orton, G.S., Hansen, C., Janssen, M.A., Bolton, S., Brown, S., Eichstaedt, G., Rogers, J., Ingersoll, A.P., Li, Ch., Momary, T.W., Tabataba-Vakili, F., Fletcher, L., Fujiyoshi, T., Greathouse, T.K., Kasaba, Y., et al., and Juno-Support Observing Team, Characterization of the great red spot from observations by Juno and the Earth-based supporting campaign, Proc. 49th DPS AAS Meeting of American Astronomical Society., Knoxville, TN, 2017, no. 205.2.Google Scholar
- Teifel’, V.G., Spectrophotometry of Jupiter Great Red Spot, Tr. Astrofiz. Inst., Akad. Nauk Kaz. SSR, 1967, vol. 9, pp. 52–58.Google Scholar
- Tejfel, V.G., Vdovichenko, V.D., Kirienko, G.A., and Kharitonova, G.A., Spectrophotometric study of the changes on Jupiter in 2009–2011, Proc. 44th Lunar and Planet. Sci. Conf., Woodlands, 2013, no. 1205, p. 2.Google Scholar
- Vdovichenko, V.D., Kirienko, G.A., Lysenko, P.G., and Teifel’, V.G., Features of the Jupiter Great Red Spot in methane absorption bands, Izv. Nats. Akad. Nauk Resp. Kaz., Ser. Fiz.-Mat., 2014, no. 4, pp. 77–84.Google Scholar
- Vdovichenko, V.D., Kirienko, G.A., and Lysenko, P.G., Methane-ammonia absorption at Jupiter during 2015 visibility season. II Equatorial and tropical zones, Izv. Nats. Akad. Nauk Resp. Kaz., Ser. Fiz.-Mat., 2015, no. 4, pp. 87–90.Google Scholar
- Vdovichenko, V.D. and Kirienko, G.A., Ammonia absorption asymmetry at Jupiter northern and southern hemispheres for 2004–2016 years, Izv. Nats. Akad. Nauk Resp. Kaz., Ser. Fiz.-Mat., 2017, no. 4, pp. 170–178.Google Scholar