ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences (Sep 2018)
NEW INSIGHTS INTO SOLAR WIND IMPLANTED VOLATILES FOR LUNAR REGOLITH CHARACTERIZATION: A SIMULATION BASED APPROACH
Abstract
The effect of solar wind implanted volatiles into the top 100 nm of the lunar regolith plays a significant role in quantitatively assessing the lunar surface isotopic composition. In essence, these volatiles can either quickly sputter out of the surface or be retained. The implantation processes exhibit a functional dependency on the surface temperature, ilmenite abundance and the activation energy associated with the optical maturity of the lunar soil. The prime focus of this study is to simulate the implication of these incident volatiles in characterizing the regolith for a better insight into the modeling of lunar exosphere during both Interplanetary Coronal Mass Ejection (ICME) and usual cases. Additionally, the proposed model quantifies the total lunar oxygen repository along with determining the associated textural and frequency domain measures for probable future lunar 3He mining sites. In this 30-day simulation, the particles bombard the reconstructed lunar grid wherein each cell displays varying particle density at a given local time. Moreover, both the activation energy and TiO2 content are assumed to be in a Gaussian distribution having (μ, σ) of (0.96, 0.025) and (12.52, 3.44) respectively. It has been found that the surfaces characterized by high activation energy tend to retain solar wind implants due to the large numbers of crystal defects. However, for H and heavy trace ions, intermediate activation energy range demonstrates diurnal behavior with the diffusive loss at local noon time. The study also finds an intriguing relationship between the lunar O2 and retained H sites (frequency domain). Furthermore, this could be utilized as a generic exospheric modeling paradigm for airless bodies and contribute to the understanding of the physical processes associated with solar astronomy.