HR: 0800h
AN: P51B-0488    [Abstracts]
TI: A Design for an Integrated Lunar Geophysics Instrument Package (L-GIP)
AU: * Neal, C R
EM: neal.1@nd.edu
AF: University of Notre Dame, Dept. of Civil Eng. & Geological Sciences, Notre Dame, IN 46556, United States
AB: The development of the Lunar Geophysics Instrument Package (L-GIP) is international collaborative investigation to record geophysical measurements on the surface of the Moon over several years (>6) and transmit the data back to Earth either directly, or via a surface or orbital relay asset. The L-GIP will include a seismometer, a heat flow probe, and a magnetometer. Each instrument that forms the L-GIP is relatively mature and was/is a payload on past, current or future planetary missions. However, the modifications to these (for integrating into one deployable unit), along with the required architecture, are needed. Significant trade studies include how to operate in an adverse thermal regime (transition between lunar night/day), long-lived power supply options, networking of different L-GIPs, defining the best design of heat flow probe to achieve the sciences goals (i.e., designs from Apollo, Lunar-A penetrator, and Rosetta missions), inclusion (or not) of a solar wind detector for the magnetic studies, and deployment strategies. The L-GIP instruments have been chosen because their individual data sets will address several unanswered scientific questions regarding the lunar interior and lunar evolution, as well as provide valuable data for exploration. The as yet unanswered science questions include: What is the composition and size of the lunar core? What is the internal structure of the whole Moon? What is the global thermal budget of the Moon and how has this impacted its evolution? Did the early Moon have a dynamo and if so, when did it start and when did it stop? Unanswered exploration questions include: What is the nature of ground movement in response to the large (body wave magnitude 5 or greater) Moonquakes that are known to occur? Do meteoroid impacts fall more in one area than another on the Moon? A global network of L-GIP instruments strategically placed around the Moon and operational for 6+ years will go a long way to answering such questions. The fundamental importance of the L-GIP is that the dataset from one instrument will enhance the datasets from the others. This is vital because using combined data types together in cooperative inversion approaches can be effective in limiting the number of acceptable interpretations. For example, magnetic data can provide good constraints on near-surface density, especially if combined with gravity data (a higher resolution data set of which will become available with the Japanese SELENE mission). The seismic models tend to resolve horizontal layers well, while magnetic approaches resolve lateral variations or vertical interfaces in subsurface magnetic susceptibility (and density if gravity data again are available). Heat flow data can provide additional lateral and sometimes (coarse) vertical property constraints, but also provide key model constraints for seismic (velocity) and density models. So, by combining these instruments in the L-GIP the datasets thus generated will dramatically lessen ambi¬guities in our understanding of the lunar interior.
DE: 5430 Interiors (8147)
DE: 6250 Moon (1221)
DE: 6297 Instruments and techniques
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting