Ground-based telescopes and space exploration have provided outstanding observations of the complexity of icy planetary surfaces. This work presents our review of the varying nature of carbon dioxide (CO2) and carbon monoxide (CO) ices from the cold traps on the Moon to Pluto in the Kuiper Belt. This review is organized into five parts. First, we review the mineral physics (e.g., rheology) relevant to these environments. Next, we review the radiation-induced chemical processes and the current interpretation of spectral signatures. The third discusses the nature and distribution of CO2 in the giant planetary systems of Jupiter and Saturn, which are much better understood than the satellites of Uranus and Neptune, discussed in the subsequent section. The final sections focus on Pluto in comparison to Triton, having mainly CO, and a brief overview of cometary materials. We find that CO2 ices exist on many of these icy bodies by way of magnetospheric influence, while intermixing into solid ices with CH4 (methane) and N-2 (nitrogen) out to Triton and Pluto. Such radiative mechanisms or intermixing can provide a wide diversity of icy surfaces, though we conclude where further experimental research of these ices is still needed.

The temporal and spatial variability of the radiation environment around Ganymede has a direct impact on the moon's exosphere, which links Jupiter's magnetosphere with the satellite's icy surface. The dynamics of the entry and circulation inside Ganymede's magnetosphere of the Jovian energetic ions, as well as the morphology of their precipitation on the moon's surface, determine the variability of the sputtered-water release. For this reason, the so-called planetary space weather conditions around Ganymede can also have a long-term impact on the weathering history of the moon's surface. In this work, we simulate the Jovian energetic ion precipitation to Ganymede's surface for different relative configurations between the moon's magnetic field and Jupiter's plasma sheet using a single-particle Monte Carlo model driven by the electromagnetic fields from a global MHD model. In particular, we study three science cases characterized by conditions similar to those encountered during the NASA Galileo G2, G8, and G28 flybys of Ganymede (i.e., when the moon was above, inside, and below the center of Jupiter's plasma sheet). We discuss the differences between the various surface precipitation patterns and the implications in the water sputtering rate. The results of this preliminary analysis are relevant to ESA's JUICE mission and in particular to the planning and optimization of future observation strategies for studying Ganymede's environment.