Date/Time: Tuesday, April 24, 2012 9:00AM PST, 16:00 UTC
Presenter: Dana Hurley, Johns Hopkins University Applied Physics Lab
“2-D Distribution of Ice in Lunar Cold Traps”
Data from neutron spectroscopy, far-ultraviolet spectroscopy, radar, and analyses of impact ejecta contribute to define the distribution and composition of volatiles in lunar polar regions. Data from any one instrument taken alone would lead one to a different conclusion about the distribution of volatiles than data taken from any other single instrument owing to the different fields of view and sensitivities of the detection techniques. The complementary nature of these data can be exploited to provide a multi-dimensional view of volatiles in lunar polar regions when combined with modeling of distribution of volatiles. We present simulations of space weathering effects on ice deposits in regions of permanent shadow on the Moon. The code conducts a Monte Carlo simulation of how space weathering processes affect the evolution of the volatiles over time, constraining the coherence of volatile deposits with depth, area, and time. The model suggests that if thermal diffusion does not play a role, then ice is buried and diluted with time. Anomalous radar craters are < 100 Myr; surface frost becomes homogenized within 20 Myr; neutron spectroscopy is sensitive to the oldest deposits; and a range of 10 m is sufficient to acquire measurements of heterogeneity.
Dana Hurley is a planetary scientist at the Johns Hopkins University Applied Physics Lab. She studies volatiles on the Moon both in the sparse exosphere and in the lunar regolith. She investigates them as a Co-I on the LRO LAMP instrument and through computer modeling as part of the NASA Lunar Science Institute. Her other research interests include planetary exploration, solar wind interactions with planets, and planetary atmospheres. She earned a Ph.D. and M.S. in Space Physics and Astronomy from Rice University and a B.A. in Physics from The Johns Hopkins University.