Unveiling cloudy exoplanets: the influence of cloud model choices on retrieval solutions

Understand

In recent years, it has become clear that a substantial fraction of transiting exoplanets have some form of aerosol present in their atmospheres.

• Transit spectroscopy - mostly of hot Jupiters, but also of some smaller planets - has provided evidence for this, in the form of steep downward slopes from blue to red in the optical part of the spectrum, and muted gas absorption features throughout.
• Retrieval studies seeking to constrain the composition of exoplanet atmospheres must therefore account for the presence of aerosols.
• However, clouds and hazes are complex physical phenomena, and the transit spectra that are currently available allow us to constrain only some of their properties.