We propose to investigate the microstructural and chemical signatures of space weathering in
sulfide grains from the Hayabusa mission. We request five polyphasic grains which include sulfide and silicate minerals of varying compositions. We will prepare these samples via a hybrid technique of ultramicrotomy and focused ion beam (FIB) sectioning for analysis in the transmission electron microscope (TEM). We will investigate the chemical characteristics of space weathered samples using nm-scale quantitative energy-dispersive X-ray spectroscopy (EDS) mapping and we will examine the Fe-oxidation state in space weathered regions of the sample via electron energy loss spectroscopy (EELS). We will employ high resolution TEM (HRTEM) imaging to examine the degree of amorphization near the surface of the sample and to identify and quantify the presence of npFe, npFeS, and/or npFeNiS particles. We will compare the space weathering characteristics across different sulfide compositions, to adjacent silicate phases present in the same grain, and to experimentally space weathered (ion and laser irradiated) sulfides samples. These analyses are important for expanding our understanding of how space weathering processes affect individual chondritic components. Such a study will maximize the scientific return of the Hayabusa mission and will be essential for the upcoming analysis of returned samples from the OSIRIS-REx and Hayabusa2 missions.