Hydrogen abundance estimation and distribution on (101955) Bennu

Asteroids were likely a major source of volatiles and water to early Earth. Quantifying the hydration asteroids is necessary constrain models formation evolution Solar System origin Life on The OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security–Regolith Explorer) mission showed that near-Earth asteroid (101955) Bennu contains widespread, abundant hydrated phyllosilicates, indicated by ubiquitous absorption at ~ 2.7 ?m. objective this work quantify hydration—that is, hydrogen content—of phyllosilicates Bennu's surface investigate how varies spatially. We analyse spectral parameters (normalized optical path length, NOPL; effective single-scattering albedo, ESPAT; Gaussian modeling) computed from phyllosilicate band spatially resolved visible–near-infrared spectra acquired OVIRS (the Visible InfraRed Spectrometer). also same using laboratory-measured meteorites including CMs, CIs, ungrouped C2 Tagish Lake. estimate mean content hydroxyl groups in be 0.71 ± 0.16 wt%. This value consistent with range some aqueously altered (CMs, Lake), but not most group (CIs). sample collection site has slightly higher than average. Spatial variations are linked geomorphology, may have been partially inherited its parent body.