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The presence of hydrated minerals and-or water on asteroids has important implications for how they comma and the Solar System comma formed and evolved. Techniques that unambiguously detect water on asteroids can be used to identify targets for exploration and in-situ resource utilization (ISRU) and could be used to better understand how water was delivered to Earth. Asteroid hydration is typically determined through detections of the near-infrared (NIR) 3-micron absorption feature however comma interpretation of this spectral feature is complicated by the need for thermal corrections to NIR data comma telluric lines in our atmosphere comma and the proximity of the OH (2.8 microns) and H2O (3 microns) spectral absorption features. In the far-ultraviolet (FUV) comma however comma water produces a strong spectral edge causing a significant difference in albedo shortward and longward of 165 nm. We propose to conduct observations of five M-type asteroids using the FUV COS G140L mode to 1) evaluate if the hydrated sub-class of the M-type asteroids are in fact hydrated or are otherwise different from the non-hydrated comma presumably metallic M-types and 2) determine if this hydration is due to OH or H2O comma since only H2O is expected to produce the strong FUV spectral signature. Only three asteroids have ever been observed at wavelengths <180 nm comma so this proposed program would significantly increase the database of FUV asteroid observations while also verifying if the FUV can be used to unambiguously detect water or water-bearing minerals on asteroid surfaces.