Global distribution of near-surface hydrogen on Mars
Neutron data observed using the Neutron Spectrometer aboard 2001 Mars Odyssey provide a lower limit to the global inventory of Martian water-equivalent hydrogen. Hydrogen-rich deposits ranging between about 20% and 100% water-equivalent by mass are found poleward of 4-50°latitude, and less rich, but significant, deposits are found at near-equatorial latitudes. The equatorial deposits between +45° latitude range between 2% and 10% water-equivalent hydrogen by mass and reach their maximum in two regions that straddle the 0-km elevation contour. Higher water abundances, up to ∼11%, are required in subsurface regolith of some equatorial regions if the upper 10 g/cm 2 of regolith is desiccated, as suggested on average by comparison of epithermal and fast neutron data. The hydrogen contents of surface soils in the latitude range between 50°and 80°north and south are equal within data uncertainties. A lower-limit estimate of the global inventory of near surface hydrogen amounts to a global water layer about 14 cm thick if the reservoir sampled from orbit is assumed to be 1 m thick. Copyright 2004 by the American Geophysical Union.
Publication Source (Journal or Book title)
Journal of Geophysical Research E: Planets
Feldman, W., Prettyman, T., Maurice, S., Plaut, J., Bish, D., Vaniman, D., Mellon, M., Metzger, A., Squyres, S., Karunatillake, S., Boynton, W., Elphic, R., Funsten, H., Lawrence, D., & Tokar, R. (2004). Global distribution of near-surface hydrogen on Mars. Journal of Geophysical Research E: Planets, 109 (9) https://doi.org/10.1029/2003JE002160