Intended as a potential aid for future space travelers, NASA has released a water map of Mars. Based on remote sensing data from the space agency's Mars Reconnaissance Orbiter (MRO) and Mars Odyssey orbiter, the new map shows areas in the higher Martian latitudes where water ice may lurk within an inch (2.5 cm) of the surface.

Currently, the single most valuable resource for manned deep space missions is water. The most obvious reason is that it's literally vital for keeping astronauts alive by providing drinking water and oxygen, but it's also important because water can be converted into rocket fuel.

Unfortunately, though water is essential for any but the simplest of robotic missions to the Red Planet, it turns out that Mars is drier than any place on Earth. This means that finding water there is more like mineral prospecting than dowsing.

On the plus side, water ice is a very strong heat conductor under Martian conditions, which can be measured by the Mars Climate Sounder on the MRO and the Thermal Emission Imaging System (THEMIS) camera and Gamma-Ray Spectrometer on Mars Odyssey, whose readings were cross-referenced with other instruments and evidence. Using this data, NASA scientists mapped out the most likely regions where a future outpost could be set up to mine water from the very shallow permafrost.

False color map of subsurface water on Mars NASA/JPL-Caltech/ASU

Traditionally, mission planners have preferred to concentrate on the warmer, sunnier regions closer to the equator, but the new satellite data and ground data from NASA's Phoenix lander have shown that the mid to polar latitudes may be more attractive for setting up manned outposts. Not only are these areas at lower elevations, which means there's more atmosphere to slow down landing spacecraft, but there's more ice to be found there.

One particularly tempting area is the Arcadia Planitia region in the northern hemisphere, where the map reveals blue and purple artificial colors, showing ice within one foot (30 cm) of the surface. However, there are also black-colored regions, which could be filled with a fine dust that a lander could sink in.

The next step will be to expand the survey to see how the subsurface ice changes throughout the Martian seasons.

"The more we look for near-surface ice, the more we find," says MRO Deputy Project Scientist Leslie Tamppari of JPL. "Observing Mars with multiple spacecraft over the course of years continues to provide us with new ways of discovering this ice."

The study was published in Geophysical Research Letters.

Source: NASA