New determination of Jupiter’s vertical cloud and haze structure using dual viewing angle MUSE/VLT observations

Jupiter is a hugely varying and diverse planet, demonstrated through spectacular changes in the cloud top appearance. However, the cloud structures which contributes to this appearance are hard to determine and are not known with certainty. A lack of in-situ observations and many unknown parameter values and numerous near-degenerate pairings within the parameter space for visible/near infrared observations of the aerosol profiles makes the problem under constrained. This work utilises several methods to alleviate these issues. Fitting simultaneously to dual viewing angle VLT/MUSE observations, using a radiative transfer algorithm, provides greater constraint to the aerosol profile than fitting to a single viewing geometry alone. To reduce the degeneracy between parameter pairings in the model, we utilise an aerosol profile with a minimised number of variable parameters by predetermining these values wherever possible. We find two clouds are needed, with a main cloud and haze layer fixed at 1.4 and 0.2 bars respectively, to successfully reproduce six years of VLT/MUSE observations (2018 - 2023), including dual angle observations of the Great Red Spot. We also retrieve an ammonia gas distribution across the disc similar to previous derived profiles, including the peak in deep volume mixing ratio at 5°N before a rapid depletion at 10°N. This cloud parameterisation successfully reproduces spectra extracted from 40°N to 40°S across the disc of Jupiter. For all locations (including the GRS) we find the material responsible for colouring Jupiter to be located in the main cloud layer (1.4 bar).