Searching for Ground Ice at the Martian Equator

The Mars Global Surveyor and Mars Odyssey results suggest that the present distribution of High-Latitude ground ice on Mars is spatially continuous from the poles to 60N and 60S. However, Mars Odyssey results show large regions at mid and equatorial latitudes with 5 to 10% equivalent water content. We are exploring the hypothesis that the mid and low latitude water observed by Odyssey is due to the presence of discontinuous, thermally stable, near-surface ground ice in localized cold niches formed by topographic relief. We use the Mars Global Surveyor Thermal Emission Spectrometer and Mars Orbiter Laser Altimeter data to map the global distribution of cold niches at high spatial resolution and compare the results with low spatial resolution maps of the global distribution of near-surface water derived from the Mars Odyssey Neutron Spectrometers.