COMPOSITIONS PHYSICAL PROPERTIES AND MOBILITY OF LIQUIDS AT HIGH PRESSURE: IMPLICATIONS FOR DIFFERENTIATION AND CORE PROPERTIES OF PLANETARY BODIES WIDESPREAD DIFFERENTIATION IN THE EARLY SOLAR SYSTEM IS SUPPORTED BY EXTENSIVE STUDIES OF METEORITES AND ASTEROIDS. DIFFERENTIATION OF LARGE PLANETESIMALS (>100 KM) AND SMALL PLANETARY BODIES AT EARLY STAGE OF THE PLANET FORMATION IS AN IMPORTANT PROCESS TO REDISTRIBUTE MATERIALS AND ENERGY IN THE INTERIORS LEADING TO THE FORMATION OF METALLIC CORES. THE DIFFERENTIATED PLANETESIMALS ALSO HAVE MAJOR IMPLICATIONS FOR THE ORIGIN OF METEORITE GROUPS AND HISTORIES OF ASTEROIDS AND PLANETS. DIFFERENTIATION CERTAINLY OCCURS IN PLANETARY BODIES IN SIZES FROM HUNDREDS OF KILOMETERS TO MARS-SIZE WHICH IS THE PROCESS THAT CAN BE SIMULATED IN HIGH-PRESSURE EXPERIMENTS IN THE RANGE OF 0.1-25 GPA. ONE OF THE KEY QUESTIONS IS HOW THE MOLTEN METAL PERCOLATED THROUGH A SILICATE MATRIX TO FORM A METALLIC CORE DURING THE EARLY DIFFERENTIATION. TO ADDRESS THIS QUESTION WE WILL SIMULATE THE METAL-SILICATE SEPARATION PROCESS DURING THE EARLY DIFFERENTIATION BY EXAMINING MOBILITY OF LIQUID METAL IN SILICATE MATRIX AND REDISTRIBUTION OF CHEMICAL COMPOSITIONS IN THE INTERIOR OF THE PLANETARY BODIES. THE FOCUS OF THIS PROPOSAL WILL BE (1) TO EXAMINE FE-NI-S LIQUID PERCOLATION IN A CHONDRITIC MANTLE COMPOSITION (MULTI-PHASE ASSEMBLAGE) IN THE PRESSURE RANGE OF 0.1-6 GPA (2) TO INVESTIGATE PERCOLATIVE BEHAVIOR AND CHEMICAL COMPOSITION OF IMMISCIBLE LIQUIDS IN THE FE-NI-S-O-SI-C SYSTEM UP TO 8 GPA AND (3) TO DETERMINE THE CHANGE OF THE DIHEDRAL ANGLE AS A FUNCTION OF DEPTH IN THE MATRIAN MANTLE. WE ARE TAKING AN INTEGRATED APPROACH TO STUDY MOBILITY AND CHEMISTRY OF CORE MATERIALS IN NATURAL COMPOSITIONS. THE EXPECTED RESULTS WILL PROVIDE INSIGHTS INTO EARLY DIFFERENTIATION PROCESSES IN LARGE PLANETESIMALS AND SMALL PLANETARY BODIES AND CORE COMPOSITION OF DIFFERENTIATED BODIES IN GENERAL. THE PROPOSED EXPERIMENTS WILL BE CONDUCTED IN THE PISTON-CYLINDER AND MULTI-ANVIL HIGH-PRESSURE DEVICES THAT ARE USED TO SIMULATE THE PRESSURE-TEMPERATURE CONDITIONS OF LARGE PLANETESIMALS AND SMALL PLANETARY BODIES DURING DIFFERENTIATION. THE PROPOSED EXPERIMENTS ARE BUILT ON OUR EXPERIENCES IN HIGH-PRESSURE SIMULATIONS AND SUCCESSFUL APPLICATIONS OF NEWLY DEVELOPED ANALYTICAL AND IMAGING TECHNIQUES TO THIS TYPE OF RESEARCH. QUANTITATIVE MEASUREMENTS OF THE PERCOLATIVE BEHAVIOR OF METALLIC LIQUID IN COMPLEX NATURAL COMPOSITIONS BECOME POSSIBLE ONLY BECAUSE OF THE DEVELOPMENT OF HIGH-RESOLUTION 3D IMAGE BY USING FOCUS-ION-BEAM/SEM CROSSBEAM INSTRUMENT OPENING A NEW RESEARCH DIRECTION IN EXPERIMENTAL SIMULATIONS OF PLANETARY PROCESSES. WE HAVE THE EXPERTISE AND RESOURCES TO ACCOMPLISH THE PROPOSED RESEARCH AND EXPECT TO OBTAIN HIGH-QUALITY DATA THAT ARE FUNDAMENTAL FOR UNDERSTANDING THE INTERIOR PROCESSES OF THE PLANETARY BODIES. THE PROPOSED RESEARCH IS WITHIN THE SCOPE OF THE EMERGING WORLDS PROGRAM INCLUDING (1) FORMATION ACCRETION AND STABILITY OF SOLAR SYSTEM BODIES AND (2) EARLY THERMAL AND CHEMICAL PROCESSES OCCURRING ON SMALL BODIES REGARDLESS OF WHETHER OR WHEN THEY DIFFERENTIATED.