Looking at lunar dust with ladee data over the past year, the lunar atmosphere and dust environment explorer (ladee) mission performed several experiments designed to determine the distribution the…

This federal contract award to the Regents of the University of Idaho, doing business as the University of Idaho, supports research to analyze data from the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission. The research will use LADEE's Ultraviolet Spectrometer (UVS) observations to characterize the spatial and size distributions of dust particles in the lunar exosphere and compare this to in-situ measurements from the LDEX instrument. The $202,063.38 grant award, which does not have a set-aside designation, is funded by the National Aeronautics and Space Administration (NASA) and aligns with the agency's high-priority lunar research areas. The findings will help ascertain whether the UVS and LDEX data are consistent and improve understanding of the lunar dust environment, which is relevant to NASA's science goals for lunar exploration and astronomy.

Looking at lunar dust with ladee data over the past year, the lunar atmosphere and dust environment explorer (ladee) mission performed several experiments designed to determine the distribution the dust-sized particles surrounding the moon. We propose to conduct a detailed analysis of the ladee remote-sensing observations obtained by the UVS instrument in order to ascertain the spatial and size distributions of the particles in the lunar exosphere, and compare these measurements with the in-situ measurements made by the ldex instrument in order to get a more complete picture of how dust is distributed around the moon. For this effort, we will use focus on three different types of UVS observations: (1) solar occultation measurements where the instrument obtains solar spectra as the sun sets behind the moon's limb, (2) observations of a fixed point in the sky relative to the sun where the instrument captures the light forward-scattered by dust grains passing through the field of view, and (3) observations staring at a fixed altitudes during sunrises and sunsets. The solar occultation spectra spectra contain narrow absorption and emission lines due to molecules in the lunar exosphere, as well as broad-band absorptions that may include contributions from small particles of dust lofted above the surface. The observations of a fixed point in space, on the other hand, should record signals due to light scattered by the dust grains. We will compare the dust signals from these various measurements to predictions from diffraction-based light-scattering models that we have previously used to interpret similar spectra of the fine particles in saturn's rings obtained by the cassini mission. Our experience with the diverse array of dusty systems in the saturn system should help US to interpret the signals seen around the moon by UVS. This work should also help US to ascertain whether the UVS data are consistent with the ldex measurements of the dust populations. This work will help in the "characterization of the global variability and structure of the lunar exosphere and/or dust environment" and is therefore falls under one of the high priority areas of lunar research called out by the ldap program. IT is also relevant to science goal 8B in the scientific context for exploration of the moon: "determine the size, charge and spatial distribution of electrostatic ally transported dust grains and assess their likely effects on lunar exploration and lunar-based astronomy."