Jupiter as an exoplanet: UV to NIR transmission spectrum reveals hazes, a Na layer, and possibly stratospheric H2O-ice clouds

Currently, the analysis of transmission spectra is the most successful technique to probe the chemical composition of exoplanet atmospheres. However, the accuracy of these measurements is constrained by observational limitations and the diversity of possible atmospheric compositions. Here, we show t...

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Bibliographic Details
Authors: Montañés-Ridríguez, Pilar, González-Merino, B., Pallé, Enric, López-Puertas, Manuel, García Melendo, Enrique José|||0000-0002-3354-1140
Format: article
Publication Date:2015
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/111904
Online Access:https://hdl.handle.net/2117/111904
https://dx.doi.org/10.1088/2041-8205/801/1/L8
Access Level:Open access
Keyword:Extrasolar planets
Jupiter (Planet)
Eclipses
Planets and satellites
Atmospheres
Gaseous planets
Jupiter
Ganymede
Planetes extrasolars
Júpiter (Planeta)
Àrees temàtiques de la UPC::Física::Astronomia i astrofísica
Description
Summary:Currently, the analysis of transmission spectra is the most successful technique to probe the chemical composition of exoplanet atmospheres. However, the accuracy of these measurements is constrained by observational limitations and the diversity of possible atmospheric compositions. Here, we show the UV – VIS – IR transmission spectrum of Jupiter as if it were a transiting exoplanet, obtained by observing one of its satellites, Ganymede, while passing through Jupiter’s shadow, i.e., during a solar eclipse from Ganymede. The spectrum shows strong extinction due to the presence of clouds (aerosols) and haze in the atmosphere and strong absorption features from CH4. More interestingly, the comparison with radiative transfer models reveals a spectral signature, which we attribute here to a Jupiter stratospheric layer of crystalline H2O ice. The atomic transitions of Na are also present. These results are relevant for the modeling and interpretation of giant transiting exoplanets. They also open a new technique to explore the atmospheric composition of the upper layers of Jupiter’s atmosphere.