SIMBAD references

2017ApJ...847...32L - Astrophys. J., 847, 32-32 (2017/September-3)

Aerosol properties of the atmospheres of extrasolar giant planets.


Abstract (from CDS):

We use a model of aerosol microphysics to investigate the impact of high-altitude photochemical aerosols on the transmission spectra and atmospheric properties of close-in exoplanets, such as HD 209458 b and HD 189733 b. The results depend strongly on the temperature profiles in the middle and upper atmospheres, which are poorly understood. Nevertheless, our model of HD 189733 b, based on the most recently inferred temperature profiles, produces an aerosol distribution that matches the observed transmission spectrum. We argue that the hotter temperature of HD 209458 b inhibits the production of high-altitude aerosols and leads to the appearance of a clearer atmosphere than on HD 189733 b. The aerosol distribution also depends on the particle composition, photochemical production, and atmospheric mixing. Due to degeneracies among these inputs, current data cannot constrain the aerosol properties in detail. Instead, our work highlights the role of different factors in controlling the aerosol distribution that will prove useful in understanding different observations, including those from future missions. For the atmospheric mixing efficiency suggested by general circulation models, we find that the aerosol particles are small (∼nm) and probably spherical. We further conclude that a composition based on complex hydrocarbons (soots) is the most likely candidate to survive the high temperatures in hot-Jupiter atmospheres. Such particles would have a significant impact on the energy balance of HD 189733 b's atmosphere and should be incorporated in future studies of atmospheric structure. We also evaluate the contribution of external sources to photochemical aerosol formation and find that their spectral signature is not consistent with observations.

Abstract Copyright: © 2017. The American Astronomical Society. All rights reserved.

Journal keyword(s): meteorites, meteors, meteoroids - planets and satellites: atmospheres - planets and satellites: composition - planets and satellites: gaseous planets - planets and satellites: individual HD 209458 b, HD 189733 b - planets and satellites: individual HD 209458 b, HD 189733 b

Simbad objects: 6

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2017ApJ...847...32L and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact