The scientists using NASA’s Mars Reconnaissance Orbiter have discovered thick deposits of ice in the mid-latitudes of Mars, courtesy of erosion wearing away surface rock on the planet. The ice layers are believed to be extended hundreds of feet deep. This discovery could reveal sensational new details about our neighbor planet.
The study authors explained that – this ice is a critical target for science and exploration: It affects modern geomorphology, is expected to preserve a record of climate history, influences the planet’s habitability, and may be a potential resource for future exploration.
Mars has a really dry appearance. But astonishingly, about 33% of the planet holds shallow ground ice. Though questions like how thick it is, how its layers look, and how pure it is – are yet to be discovered, it is still a huge step forward.
8 different exposed ice deposits on the planet, spotted by the HiRISE camera of the orbiter, have already been examined. Among them, 7 are believed to be pole-facing scarps i.e, steep banks or slopes, seen in the southern hemisphere. The one left is detected to be a cluster of scarps in Milankovic Crater, northern hemisphere.
According to the scientists – “the scarps are sharply defined and nearly straight, up to (about 3.7 miles) long, and face slightly east of poleward.”
The ice layer has a layer of rock and dust cemented over it. Starting at a depth of just 1 to 2 meters beneath the surface, these ice deposits could extend to more than 100 meters or 328 feet deep. The layers contain ice that is unexpectedly pure in terms of composition. The scientists had predicted the ice to contain a lot of dust or dirt.
One of the scarps was quite interesting. With a number of boulders falling out due to the ice retreat, the scientists could compare before-and-after images. They could calculate the rate at which the ice was shrinking back. The calculated result was around a few millimeters every summer. Snow or frost that fell on that planet is being held responsible for being recrystallized, forming those ice deposits. The procedure is quite the same for the glaciers on Earth.
The study authors explained it: “This interpretation is consistent with the high ice content and the mantling appearance of the host unit.”
Tiny, prehistoric samples of air are often trapped inside the Air pockets in the ice. Information can be traced by analyzing that air. Scientists have their fingers crossed to find some of these inside the Martian ice samples excavated by erosion.
The authors have explained it: “These shallow depths make the ice sheets potentially accessible to future exploration and the scarps present cross-sections of these ices that record past episodes of ice deposition on Mars.”