SCIENCE GOALS AND OBJECTIVES: RECENT NEW HORIZONS RESULTS AND GROUND-BASED OBSERVATIONS SUPPORT THE PRESENCE OF NH3 ON THE SURFACE OF CHARON PLUTO S LARGEST MOON. NH3 HAS ALSO BEEN FOUND ON THE SURFACES OF THE SMALLER MOONS NIX AND HYDRA AS WELL AS ON THE SURFACES OF ORCUS AND QUAOAR. THIS IS UNUSUAL SINCE NH3 SHOULD NOT SURVIVE ON THE SURFACE OF THESE ICY BODIES FOR LONGER THAN A FEW MILLION YEARS DUE TO THE PROTON RADIATION FLUX IN THE OUTER SOLAR SYSTEM. AS OF TODAY NO MECHANISM FOR PRESERVING NH3 ON THE SURFACE OF THESE BODIES HAS BEEN ACCEPTED AS DEFINITIVE. FOR CHARON MECHANISMS SUCH AS CRYOVOLCANISM HAVE BEEN SUGGESTED TO EXPLAIN THE PRESENCE OF THIS ICE BUT THESE ARE NOT CONSISTENT WITH A MOON TOO SMALL TO SUSTAIN A SUBMERGED LIQUID OCEAN. ANOTHER POSSIBLE EXPLANATION IS THAT NH3 IS ONE OF THE PRIMORDIAL CONSTITUENTS OF CHARON. SUBSURFACE NH3 WOULD THEN BE DIFFUSING UP INTO CHARON S SURFACE H2O ICE LAYER. BASED UPON THE BROADENED SHAPE OF CHARON S 2.21 M BAND NH3 ALSO APPEARS TO BE COMPLEXED IN H2O IN DIFFERENT WAYS AND IN DIFFERENT AMOUNTS THUS ADDING TO THE UNCERTAINTY OF ITS ORIGIN. THIS PROPOSAL SEEKS TO IMPROVE OUR UNDERSTANDING OF THE STABILITY OF NH3/H2O ICES AS A FUNCTION OF ICE STRUCTURE CONCENTRATION AND TEMPERATURE AND TO PROVIDE NEAR-IR SPECTRAL DATA OF NH3 IN H2O ICES THAT WILL BE CRITICAL FOR THE INTERPRETATION OF OBSERVATIONS OF OUTER SOLAR SYSTEM BODIES.