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We present a detailed theoretical exploration of the refractory compositions and volatile enrichments of planets forming in protoplanetary disks with solar-like conditions. The two cases of the Sun and WASP-12 are studied due to the availability of spectral measurements and their known planets. The distribution throughout their disks of solid compounds with a wide range of volatilities is computed by a comprehensive chemical thermodynamics code. After the calculation of refractory compounds down to the water snowline, the compositional distributions are documented for planets generated in certain locations of protoplanetary disks depending on thermodynamic conditions. These results are referred to proposed bulk compositions for solar terrestrial planets, and for the core of the hot Jupiter WASP-12b. The material left over after the formation of rocky components is collected and treated in calculations to determine the abundances of fundamental volatile molecules in the outer regions of the disks. The distributions of planetesimal volatile composition are then altered for four different cases of the carbon-to-oxygen ratios, and for oxidizing and reducing conditions, in order to adjust the best fit for the accretion zone of Jupiter and WASP-12b. We compare the Jovian results to in situ atmospheric measurements from Jupiter's atmosphere. Overall, this study proposes a holistic approach to estimate possible planetary interior and envelope compositions from hot toward cold disk zones, along with the mass of planetesimals accreted into the envelopes of gas giants. [ABSTRACT FROM AUTHOR]

Over the past eight years, the Visual and Infrared Mapping Spectrometer (VIMS) on board the Cassini orbiter has returned hyperspectral images in the 0.35-5.1 μm range of the icy satellites and rings of Saturn. These very different objects show significant variations in surface composition, roughness, and regolith grain size as a result of their evolutionary histories, endogenic processes, and interactions with exogenic particles. The distributions of surface water ice and chromophores, i.e., organic and non-icy materials, across the Saturnian system, are traced using specific spectral indicators (spectral slopes and absorption band depths) obtained from rings mosaics and disk-integrated satellites observations by VIMS. Moving from the inner C ring to Iapetus, we found a marking uniformity in the distribution of abundance of water ice. On the other hand, the distribution of chromophores is much more concentrated in the rings particles and on the outermost satellites (Rhea, Hyperion, and Iapetus). A reduction of red material is observed on the satellites' surfaces orbiting within the E ring environment likely due to fine particles from Enceladus' plumes. Once the exogenous dark material covering the Iapetus' leading hemisphere is removed, the texture of the water ice-rich surfaces, inferred through the 2 μm band depth, appears remarkably uniform across the entire system. [ABSTRACT FROM AUTHOR]