NASA’s Mars Reconnaissance Orbiter (MRO) has found evidence of water ice on the Red Planet buried in the ground at the Utopia Planitia region. The region has enough water ice to fill the Lake Superior – the largest of the Great Lakes in North America, a study has said.
University of Texas, Austin, scientists have studied the data collected by ground-penetrating Shallow Radar (SHARAD) instrument on board the MRO to find water ice as thick as 80 metres to about 170 metres hidden underneath the soil at the Utopia Planitia region on Mars.
Scientists say that the latitudes at which the water ice has been found, the harsh conditions won’t allow the water ice to persist as it would sublime into water vapour in the planet’s thin, dry atmosphere. Because the ice at this region is buried, it is shielded from the atmosphere by a soil covering estimated to be one to 10 metres thick. The composition of the ice is said to containt at least 50 to 85 per cent water ice, mixed with dust or larger rocky particles.
The ice deposits could have formed because of snowfall during a period in Mars history when the planet’s axis was more tilted than it is today. Mars accumulates large amounts of water ice at the poles. In cycles lasting about 120,000 years, the tilt varies to nearly twice that much, heating the poles and driving ice to middle latitudes. Studies have shown that frozen water accumulates away from the poles during high-tilt periods.
The newly surveyed ice deposit spans latitudes from 39 to 49 degrees within the plains. It represents less than one per cent of all known water ice on Mars, but it more than doubles the volume of thick, buried ice sheets known in the northern plains.
Researchers say that the ice deposits close to the surface of Mars could prove to be a vital resource for humans once they reach more because it will be much more accessible than most water ice on Mars. This is because the location of these particular ice deposits are at a relatively low latitude and lies in a flat, smooth area where landing a spacecraft would be easier than at some of the other areas with buried ice.
The Utopian water is all frozen now. If there were a melted layer – which would be significant for possibility of life on Mars – it would have been evident in the radar scans.
The study is published in the journal Geophysical Research Letters