SCIENCE GOALS AND OBJECTIVES: THE GOAL OF THE PROPOSED STUDY IS TO USE METER-TODECAMETER- RESOLUTION TOPOGRAPHY AND RADAR DATA TO EXAMINE CRATERS ON THE MOON WITH THE OBJECTIVES OF: (1) CONSTRAINING THE RATES AND PROCESSES LEADING TO CRATER DEGRADATION AND TOPOGRAPHIC EVOLUTION ON THE MOON (2) USING VARIATIONS IN FRESH CRATER MORPHOMETRY TO EXPLORE PHYSICAL CHARACTERISTICS OF THE CRUST AND REGOLITH AND (3) COMPARING RADAR PROPERTIES AND TOPOGRAPHIC CHARACTERISTICS OF CRATERS IN A RANGE OF DEGRADATION STATES TO EXPLORE REGOLITH EVOLUTION IN RESPONSE TO IMPACT GARDENING. METHODOLOGY: WE PROPOSE TO MAKE NEW MEASUREMENTS OF THE TOPOGRAPHY OF CRATERS ON HIGHLANDS SURFACES TO ASSESS WHETHER THE DEGRADATION SEQUENCE FOR THE MARIA IS CONSISTENT WITH MEASUREMENTS IN THE HIGHLANDS. SECOND WE PROPOSE FURTHER TESTS OF THE LINEAR DIFFUSION MODEL FOR CRATER DEGRADATION TO DETERMINE IF THERE IS SOME SCALE-DEPENDENCE OR NON-LINEARITY IN THE WAY LUNAR TOPOGRAPHY EVOLVES THAT NEEDS FURTHER CHARACTERIZATION. SPECIFICALLY BY MEASURING THE TOPOGRAPHY AND CRATER STATISTICS IN SATURATION (FOR D ~10 TO 200 M DIAMETER CRATERS) WE CAN TEST WHETHER THE KM-SCALE DIFFUSION RATE IS RECONCILABLE WITH THE EVOLUTION OF SMALLER FEATURES. THIRD WE WILL USE MINI-RF RADAR MEASUREMENTS OF LUNAR CRATERS THAT HAVE DISTINCTIVE RADAR HALOS TO ASSESS HOW THE RADAR PROPERTIES CHANGE WITH TIME COMPARED TO THEIR TOPOGRAPHY. CO-I THOMSON WILL LEAD THIS THIRD TASK AND IN ADDITION HE WILL BE AN ACTIVE PARTICIPANT AND CONTRIBUTOR TO THE DATA ANALYSIS INTERPRETATION AND PUBLICATION PREPARATION AS PART OF ALL OTHER TASKS.