Several remote observations have indicated that water ice may be presented in permanently shadowed craters of the Moon. The Lunar Crater Observation and Sensing Satellite (LCROSS) mission was designed to provide direct evidence. On 9 October 2009, a spent Centaur rocket struck the persistently shadowed region within the lunar south pole crater Cabeus, ejecting debris, dust, and vapor. This material was observed by a second "shepherding" spacecraft, which carried nine instruments, including cameras, spectrometers, and a radiometer. Near-infrared absorbance attributed to water vapor and ice and ultraviolet emissions attributable to hydroxyl radicals support the presence of water in the debris. The maximum total water vapor and water ice within the instrument field of view was 155 ± 12 kilograms. Given the estimated total excavated mass of regolith that reached sunlight, and hence was observable, the concentration of water ice in the regolith at the LCROSS impact site is estimated to be 5.6 ± 2.9% by mass. In addition to water, spectral bands of a number of other volatile compounds were observed, including light hydrocarbons, sulfur-bearing species, and carbon dioxide.

In some large solar energetic particle (SEP) events, the intensities of higher energy SEPs decay more rapidly than at lower energies. This energy dependence varies with particle species, as would be expected if the decay timescale depended on a rigidity-dependent diffusion mean free path. By comparing the decay timescales of carbon, nitrogen, oxygen, neon, magnesium, silicon, sulfur, and iron, mean charge states are inferred for these (and other) elements in three SEP events between 1997 and 2002 at energies between 10 and 200 MeV nucleon À1 . In a fourth event, upper limits for the charge states are inferred. The charge states of many different particle species are all consistent with a single source temperature; in two events in 1997 and 2002, the best-fit temperature is much higher than that of the corona, which could imply a contribution from solar flare material. However, comparison with lower energy iron charge states for the 1997 event implies that the observed high-energy charge state could also be understood as the result of stripping during shock acceleration in the corona. Subject headingg s: acceleration of particles -methods: data analysis -Sun: particle emission

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Mean ionic charge states for SEP events can reflect source temperatures, stripping during acceleration and transport, and the composition of source material.Multi-spacecraft measurements of mean ionic charge states for single SEP events can also demonstrate longitudinal dependence depending on seed particle composition or acceleration conditions. in previous studies, we calculated inferred high-energy ionic charge states for SEP events. The analysis method fits the energy dependence of decay times for each element in SEP events, combined with charge-to-mass ratios relative to a calibration element, and derives mean charge state estimates for elements from O to Fe. Previously, we applied the method using ACE and STEREO data to SEP events through the beginning of 2012, in order to elucidate evidence on seed populations or longitudinal variations with charge state for single SEP events, with varying results. In this paper, we continue applying the method to new SEP events from 2012 to 2015 in the ACE and STEREO data. With the three spacecraft widely spread apart during this time period, there are fewer single SEP events with multi-spacecraft data, but the wide spacing allows more SEP candidate events to be considered, separately, than would be available with just a single spacecraft. Our new results for two SEP events continue to be consistent with observed correlation between Q(Fe) and Fe/O in previous events.

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