This thesis integrates thermodynamic modeling tools, laboratory analyses of meteorites, and telescopic observations to characterize the chemical processes occurring on objects within our solar system. It addresses two fundamental questions: 1. How can we link meteorite samples to in situ observations to explain the origins of rocks found in situ and to provide insights into the evolution of a planet’s interior? 2. How can the geographic distribution of an object's surface composition suggest information about its interaction with its interior? This thesis addresses these questions through case studies focusing on Martian meteorites and Europa's surface, respectively. Chapter II presents fractional crystallization models using parental magma composition calculated from NWA 2737 melt inclusions as starting compositions. Thermodynamic modeling software, MELTS, is used to model fractional crystallization of Northwest Africa (NWA) 2737 parental magma compositions with a wide range of parameters (pressure, water content, oxygen fugacity). Our models show that the felsic compositions recently analyzed at the Martian surface in Gale Crater, especially Sparkle and Angmaat, the two rocks thought to be analogous to the earliest continental crust on Earth, can be obtained by fractional crystallization of chassignite-like parental melts. Our results suggest a link between the processes that resulted in chassignites and the rocks analyzed in situ at Gale Crater. To assess the possible scenarios for Martian magma migration and storage processes, we compared chassignites to terrestrial analogs formed via various mechanisms and proposed two mechanisms that may explain the intrusive and effusive rocks found in situ at Gale Crater: 1) emplacement and fractionation in a closed-system crustal reservoir; and 2) eruption of mafic to intermediate lavas of a relatively open-system subject to constant replenishment. Chapter III presents the application of nano-XCT for non-destructive 3D phase analysis and estimation of phase abundances in rare Martian meteorite samples, specifically chassignite NWA 2737. In this chapter, we determine the most suitable laser power for minimizing artifacts and maximizing phase contrast. By utilizing nano-XCT, we successfully identify and segment primary phases in the bulk meteorite sample. Additionally, we are able to locate and segment crystallized silicate melt inclusions within the meteorite. The phase abundances in bulk NWA 2737 and within melt inclusions calculated using nano-XCT are in good agreement with previous studies that used thin section calculations, demonstrating the reliability of nano-XCT as a non-destructive alternative for estimating bulk phase abundances in rare samples. This study develops a benchmarking protocol and demonstrates the efficacy of nano-XCT as a non-destructive technique for generating an overview of phase distribution and assemblages of melt inclusions within rare samples. Future research can benefit from combining non-destructive 3D phase assemblage estimations with non-destructive 3D chemical analysis techniques to achieve a fully non-destructive parental magma composition estimation of rare cumulate samples. In chapter IV, we use observations of Europa from the NASA Infrared Telescope Facility, Keck Observatory, and JWST to disentangle the potential effects of temperature and composition. In order to isolate the effect of temperature on Europa's H₂O₂, we use the ground-based observations to assess its response to temperature changes over timescales associated with Europa's daily eclipse and diurnal cycle. We use JWST Cycle 1 data to look for any geographic correlation between Europa's H₂O₂ and CO₂. Both changes in Europa's 3.5-μm H₂O₂ absorption band from pre to post eclipse and across a local day suggest minimal effects of the local temperature on these timescales. In contrast, the JWST observations show a strong positive correlation between Europa's H₂O₂ and CO₂ bands, supporting the previously suggested possibility that the presence of CO₂ in the ice may enhance H₂O₂ concentrations via electron-scavenging. Chapter V presents the first global, spatially resolved Mid-UV (200-315 nm) spectra of Europa obtained with Hubble Space Telescope (HST)/ Space Telescope Imaging Spectrograph (STIS) to constrain the origins of Europa’s mid-UV absorption features. We map both the 280-nm SO₂ feature and the 230-nm feature across trailing, leading, anti-Jovian, and sub-Jovian hemispheres. With an adequate spatial resolution to differentiate resurfaced terrain from the background radiolytic processing patterns, we confirm that the distribution of SO₂ is primarily influenced by exogenic radiolytic sulfur from Io or electrons influenced by Jupiter’s magnetic field, with minimal correlation to the geological chaos terrains. Additionally, we verify the identification of the 230 nm feature as irradiated NaCl and its strong association with the leading chaos terrains. These results enhance our understanding of Europa's chemistry and provide valuable insights that complement ongoing planetary missions with additional coverage and wavelengths.