  Deducing the cloud cover and its temporal evolution from the observed
planetary spectra and phase curves can give us major insight into the
atmospheric dynamics. In this paper, we present Aeolus, a Markov-Chain Monte
Carlo code that maps the structure of brown dwarf and other ultracool
atmospheres. We validated Aeolus on a set of unique Jupiter Hubble Space
Telescope (HST) light curves. Aeolus accurately retrieves the properties of the
major features of the jovian atmosphere such as the Great Red Spot and a major
5um hot spot. Aeolus is the first mapping code validated on actual observations
of a giant planet over a full rotational period. For this study, we applied
Aeolus to J and H-bands HST light curves of 2MASSJ21392676+0220226 and
2MASSJ0136565+093347. Aeolus retrieves three spots at the top-of-the-atmosphere
(per observational wavelength) of these two brown dwarfs, with a surface
coverage of 21+-3% and 20.3+-1.5% respectively. The Jupiter HST light curves
will be publicly available via ADS/VIZIR.
