TO BETTER UNDERSTAND THE ACCRETION OF VOLATILES TO TERRESTRIAL PLANETS SMALL PLANETARY BODIES AND THE MOON AND THEIR DISTRIBUTION OWING TO INITIAL DIFFERENTIATION WE PROPOSE TWO PROJECTS. THE FIRST FOCUSES ON THE ROLE OF MAGMATIC H2 IN THE ACQUISITION OF HYDROUS COMPONENTS IN ACCRETING PLANETS AND PROTOPLANETARY EMBRYOS. THE SECOND EXTENDS OUR STUDIES OF H AND F IN SILICATE MINERALS FROM THE MOON. MAGMATIC MOLECULAR H2 IN EARLY PLANETARY DIFFERENTIATION KEY OBJECTIVES: WE WILL DETERMINE THE SOLUBILITY OF H2 IN PLANETARY MAGMAS IN ORDER TO BETTER UNDERSTAND H MASS TRANSFER AND ASSOCIATED CHEMICAL REACTIONS DURING DIFFERENTIATION OF SMALL AND LARGE BODIES IN THE EARLY SOLAR SYSTEM. BOTH HYDROGEN GAS AND SILICATE MAGMAS WERE ABUNDANT DURING PLANETESIMAL AND PROTOPLANET ACCRETION AND DIFFERENTIATION. UNDER REDUCING CONDITIONS MAGMAS DISSOLVE H IN PART AS MOLECULAR H2 WHICH ALLOWS DIRECT INGASSING OF NEBULAR H2 TO PLANETARY EMBRYOS AND PROTOPLANETS AND MAY FACILITATE OUTGASSING OF MAGMA OCEANS TO PRIMORDIAL ATMOSPHERES. SOME INGASSED H2 MAY BE RETAINED IN EARLY PLANETARY MANTLES AND SOME MAY PARTITION INTO METALLIC CORES. REDOX REACTIONS BETWEEN THE DIFFERENT FORMS OF MAGMATIC H (H2O AND H2) AND FE (FEO METALLIC FE) HAVE IMPORTANT CONSEQUENCES FOR SEQUESTRATION OF H IN CORES AND FOR THE OXIDATION STATE OF MANTLES. SOLUBILITY OF H2 IN MAGMAS REMAINS POORLY QUANTIFIED. NO DATA ARE AVAILABLE ON COMPOSITIONS RELEVANT TO EARLY PLANETARY DIFFERENTIATION AND THE TEMPERATURE DEPENDENCE IS NOT KNOWN. CRUCIALLY ANALYTICAL QUANTIFICATION REMAINS HIGHLY UNCERTAIN. PREVIOUS EXPERIMENTS WERE QUANTIFIED USING FTIR ABSORPTION COEFFICIENTS CALIBRATED FROM SIO2 GLASS BUT THE CALIBRATION COULD BE QUITE DIFFERENT FOR NATURAL ALUMINOSILICATE GLASSES. METHODS AND TECHNIQUES: WE PROPOSE THE FIRST MEASUREMENT OF IR ABSORPTION COEFFICIENTS FOR ALUMINOSILICATE GLASSES BY GRAVIMETRY AND SIMS (TASK 1) AND NEW H2 SOLUBILITY EXPERIMENTS TO CALIBRATE AN IONIC POROSITY MODEL THAT WILL PREDICT H2 SOLUBILITY AS A FUNCTION OF PRESSURE TEMPERATURE AND MELT COMPOSITION (TASK 2). WE WILL APPLY THESE TO INGASSING AND OUTGASSING OF H2 DURING PROTOPLANET AND PLANETARY ACCRETION AND DIFFERENTIATION. LUNAR F AND H FROM STUDY OF SILICATE MINERALS KEY OBJECTIVES: WE WILL DOCUMENT THE VOLATILE INVENTORY OF THE MOON IN ITS EARLIEST STAGES OF DIFFERENTIATION BY HIGHLY SENSITIVE ANALYSIS OF F AND H IN LUNAR SILICATE MINERALS. THE ABUNDANCES OF LUNAR VOLATILES THEIR DELIVERY AND RETENTION REMAIN CONTROVERSIAL. IN CONTRAST TO EARLY FTIR RESULTS OUR SIMS ANALYSES INDICATE THAT PLAGIOCLASE FROM FERROAN ANORTHOSITES ARE NOW CHIEFLY DRY THOUGH THEY MAY HAVE CONTAINED GREATER H DURING THEIR FORMATION. IN CONTRAST THE PLAGIOCLASE RETAIN SMALL AMOUNTS OF F. GIVEN APPROPRIATE PARTITION COEFFICIENTS THIS WOULD ALLOW CALCULATION OF THE F CONTENT OF THE LMO AND CONSTRAIN THE ACQUISITION OF MODERATELY VOLATILE ELEMENTS DURING LUNAR ACCRETION. PAIRED WITH OH/F RATIOS DETERMINED FROM APATITE DIRECT DETERMINATION OF F IN LUNAR MAGMAS FROM PLAGIOCLASE AND PYROXENE COULD PROVIDE REFINED CONSTRAINTS ON H2O IN IMPORTANT LUNAR RESERVOIRS. METHODS AND TECHNIQUES: IN TASK 3 WE WILL USE SIMS TO DETERMINE F (AND IF PRESENT H) IN MG-SUITE ROCKS AND K-RICH AND AL-RICH BASALTS TO CONSTRAIN THE F AND H2O CONTENT OF KREEP-RELATED MAGMAS. IN TASK 4 WE WILL CONDUCT HIGH TEMPERATURE AND HIGH PRESSURE PARTITIONING EXPERIMENTS OF F THAT ARE NEEDED TO CONVERT OBSERVATIONS FROM PLAGIOCLASE TO MAGMAS OF THE LMO AND THEREFORE TO UNDERSTAND THE ORIGIN AND FATE OF VOLATILES ON THE EARLY MOON. RELEVANCE TO EMERGING WORLDS INTERACTIONS BETWEEN HYDROGEN AND MOLTEN SILICATE ARE A KEY MODE OF MASS TRANSFER DURING FORMATION AND DIFFERENTIATION OF PLANETESIMALS EMBYROS AND PROTOPLANETS. EVIDENCE OF ABUNDANCES OF F AND H IN THE EARLY MOON DOCUMENTS THE ACQUISITION AND RETENTION OF VOLATILE MATERIAL DURING FORMATION AND DIFFERENTIATION OF THE EARTH-MOON SYSTEM.