Water ice lurks just meters beneath the Martian surface at one of the most dramatic sites on the Red Planet. This finding is the result of a recent study based on data collected by the Trace Gas Orbiter (TGO).
Quoted from Space.com, TGO is part of the ExoMars mission operated by the European Space Agency (ESA) and its Russian partner, Roscosmos. ExoMars includes TGO, which launched in 2016, and the rover Rosalind Franklin, which will launch to Mars next year.
Among the instruments on board the TGO, is one called the Fine Resolution Epithermal Neutron Detector (FREND), which can detect hydrogen, one of the two elements that make up water. New analysis of FREND's data shows high hydrogen levels at a site called Candor Chaos, which lies near the heart of a massive canyon system dubbed Valles Marineris.
"We found that the center of Valles Marineris is full of water, much more water than we expected," said Alexey Malakhov, a senior scientist at the Space Research Institute of the Russian Academy of Sciences.
"This is very similar to Earth's permafrost regions, where water ice permanently persists beneath dry soil due to the constant low temperatures."
Valles Marineris is the largest canyon in the Solar System. It is 10 times longer and five times deeper than Earth's Grand Canyon, and is one of the most striking features of Mars.
This canyon runs along most of the Martian equator. When scientists had searched for liquid ice on Mars in the equatorial region before, they had only been able to study surface dust, and they had found only small amounts of water.
This new research expands the depths that scientists can study and gives them new insights into the subsurface as well as the immediate surface of Mars.
"With TGO we can look up to a meter below this dusty layer and see what's really going on beneath the Martian surface, and, most importantly, find water-rich 'oases' that could not be detected with previous instruments," said Igor Mitrofanov, scientist Space Research Institute of the Russian Academy of Sciences.
The researchers say that if all the hydrogen they detected was present in the form of water ice, the valuable compound could form as much as 40% of the near-surface material in the area.
However, FREND can also detect water contained in local minerals, although scientists believe it is less likely than ice.
"This finding is a great first step, but we need more observations to know for sure what form of water we are finding," Håkan Svedhem, former ESA project scientist for the ExoMars Trace Gas Orbiter.
"Regardless of the results, these findings demonstrate the unmatched capabilities of the TGO instrument in allowing us to 'see' beneath the Martian surface, and reveal a large, not-so-deep, and easily exploitable reservoir of water in this region of Mars."