Massive subsurface slopes of water ice have been detected in the Martian mid-latitudes, natural resources that might make the most necessary ingredient of life more accessible than previously thought to future human permanent bases on the Red Planet, our most probable cosmic destination for a rainy day.
A group of scientists, using daily images beamed back from NASA’s Mars Reconnaissance Orbiter (MRO) during the past 11 years, managed to detect eight sites where colossal ice deposits near the Mars’ surface are exposed on steep slopes, up to 100 meters high, located mostly in the planet’s southern hemisphere.
The discovery not only can help planetary geologists to study, with more details, a layer-cake record of past Martian climates, but it also significantly boosts the survival probability of future manned mission to the planet, as the extracted ice can either be turned into drinking water or combined with carbon dioxide -- the main component of Mars’ atmosphere -- to generate oxygen to breathe, and methane, a rocket propellant.
“There is shallow ground ice under roughly a third of the Martian surface, which records the recent history of Mars,” said Colin Dundas, the US Geological Survey geologist, who led the study and co-discovered the ice layers, adding, “What we've seen here are cross-sections through the ice that give us a 3-D view with more detail than ever before.”
Scientists have long speculated that large reserves of water ice are trapped underground on the Red Planet. Back in 2002, the NASA Odyssey mission conducted orbital scan of the Martian surface and spotted signs of shallow ground ice at high latitudes.
In 2008, the NASA Phoenix mission extracted water ice from its landing site near the Martian north pole. And in November 2016, planetary geologists, using the MRO, discovered a buried ice sheet at Mars’s mid-latitudes that holds about as much water as Lake Superior. The recent discovery, however, gave scientists a much more vivid picture of the extent and accessibility of Mars’ subsurface ice layers.
According to Dundas, the newly-found ice sites support the notion that the planet’s mid-latitudes periodically saw large snowfalls millions of years ago, when Mars was tilted on its axis at a steeper angle than it is today.
“It's like having one of those ant farms where you can see through the glass on the side to learn about what's usually hidden beneath the ground,” said co-author of the study Shane Byrne of the University of Arizona's Lunar and Planetary Laboratory.
He added that the discovered sites are located at latitudes with less hostile conditions than at Mars’ polar ice caps. “Astronauts could essentially just go there with a bucket and a shovel and get all the water they need.”