Water ice has been delivered to the lunar poles from different sources over billions of years, but this accumulation was punctuated by large impacts that excavated dry regolith from depth and emplaced it in layers over the poles. Here, we model the resulting stratigraphies of ice and ejecta deposits in the lunar polar regions. Large polar craters were age dated, and their ejecta distributions calculated with standard scaling relations. We then created a Monte Carlo model for ice deposition and ejecta emplacement. Typical model runs showed that deposits in older cold traps (>4 Ga) are divided into two zones: buried ice-rich gigaton deposits and younger more gardened mantles. The latter are consistent with small crater morphometry measurements, but the existence of substantial ice buried at great depths is more difficult to confirm. Rare outlier model runs included Mercury-like cases with significant deposition events in recent history (<200 Ma). Plain Language Summary The polar regions of Earth's Moon have topographic depressions that are never directly exposed to the Sun, so they are cold enough for deposits of ice to exist. Water can get into these regions by water-bearing asteroids colliding with the Moon, or from lunar volcanoes erupting gases that travel to the poles. At the same time, large impact craters that form at the poles eject an enormous amount of soil and rock that could bury existing ice. It is not well understood how these two processes work together to build up deposits that may have alternating layers of ice-rich and ice-poor soil. In this study, we used computer simulations to predict what these layered deposits may look like. We found it is likely that large amounts of relatively pure ice are buried at depth in the oldest deposits, covered with thinner layers hosting less ice. Impact cratering has been the dominant process affecting the lunar poles, but the effects of large polar craters on nearby ice deposits have not been previously addressed. Impact effects have been considered for micrometeoroids (e.g.,

Thirty silicate glasses were synthesized as realistic analogs to those expected to exist on Mars, the Moon, and Mercury. Samples were measured using visible/near‐infrared and Mössbauer spectroscopy to determine the effects of varying bulk chemistry, oxygen fugacity, and temperature on spectral properties. For Martian glasses, the fO2 during fusion strongly affects absorption band intensities in the spectra, while bulk chemistry has noticeable secondary effects on absorption band positions. Titanium and iron content drive spectral changes in lunar glasses, where Fe3+ is effectively absent. Iron‐free Mercury analog glasses have much higher albedos than all other samples, and their spectral shape is a close match to some pyroclastic deposits on Mercury. Synthetic glass spectra were used as inputs into a spectral unmixing model applied to remote orbital datasets to test for the presence of glass. The model is validated against physical laboratory mixture spectra, as well as previous detections of glass‐rich pyroclastic deposits on the Moon. Remote data were then used from suspected impact deposits and possible pyroclastic deposits on Mars as a new application of the model: the results reveal spatially coherent glass‐rich material, and the strong spectral match of the synthetic glasses to these remotely sensed data gives new insights into the presence and character of glasses on the Martian surface. The large library of glass spectra generated here, acquired from consistently synthesized and measured samples, can serve as a resource for further studies of volcanic and impact processes on planetary bodies.

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