  We extend a data-based model-free multifractal method of exoplanet detection
to probe exoplanetary atmospheres. Whereas the transmission spectrum is studied
during the primary eclipse, we analyze the emission spectrum during the
secondary eclipse, thereby probing the atmospheric limb. In addition to the
spectral structure of exoplanet atmospheres, the approach provides information
to study phenomena such as atmospheric flows, tidal-locking behavior, and the
dayside-nightside redistribution of energy. The approach is demonstrated using
Spitzer data for exoplanet HD189733b. The central advantage of the method is
the lack of model assumptions in the detection and observational schemes.
