Researchers broke the news in a journal report published Thursday, revealing the ice sheets they found just below the surface extend about 300 feet down and could explain much about the planet's past climate. Since there are few craters on the surface at these sites, the authors propose that the ice was formed relatively recently. The ice could be a useful source of water for future missions to Mars. What's more, bands and variations in color suggest that the ice contains distinct layers, which could be used to understand changes in Mars' climate over time (the ice sheets themselves likely formed as snow accumulated over time).
A team of scientists, led by Colin Dundas, a geologist at the US Geological Survey, analyzed data from the Mars Reconnaissance Orbiter (MRO), specifically looking at eight areas where erosion occurred. "What we've seen here are cross-sections through the ice that give us a 3-D view with more detail than ever before". Whilst water ice is known to be present in some locations on Mars, many questions remain about its layering, thickness, purity, and extent. By combining different images together, as shown above, the composite images can reveal the subtle differences in how the surface absorbs and reflects light, and thus provide information about what makes up the surface. With this combination, normal surface dust and minerals come out as the peach colour, while water ice stands out bright blue. The water could be used for drinking and potentially conversion into oxygen to breathe.
This exposed ice is slowly sublimating away, turning directly from solid to vapour, because even though temperatures on Mars are well below freezing, the air pressure is too thin for the ice to hold its solid shape. The size of the deposit, however, means that it will be a very long time before it completely sublimates into the atmosphere.
"Humans need water wherever they go, and it's very heavy to carry with you".