Mars is currently thought to be dry, dusty, and arid. The Earth's blue-green surface, which is rich in water, appears to be the opposite of the Red Planet. But water once flowed over Mars' surface, sculpting rivers' paths and leaving behind the remains of lake beds. Water is still present on the planet below the dusty surface, where it is trapped in enormous blocks of ice that have been deposited. Although these water ice deposits have previously been seen close to Mars' polar ice caps, a recent announcement from the European Space Agency (ESA) indicates that significant deposits may be hidden beneath the enigmatic Medusae Fossae Formation (MFF) dust mound.
The Mars Express spacecraft of the European Space Agency provided the latest dating that implies the presence of these ice deposits. After scanning the region in 2007 with its MARSIS radar, the Mars Express discovered something hidden beneath the shifting dust mounds. The fact that the dust didn't settle and become more compacted actually hinted at what might be underneath. Recently released data from the MARSIS radar hints at the specific material that is deposited. These deposits have a maximum thickness of 3.7 kilometres (2.3 miles).
“Excitingly, the radar signals match what we’d expect to see from layered ice, and are similar to the signals we see from Mars’ polar caps, which we know to be very ice-rich,” says Thomas Watters of the Smithsonian Institution, led the current Mars research.
There are enormous ice deposits. If the water melted, it would create a shallow ocean that is 1.5–2.7 meters (4.9–8.9 feet) deep, covering the surface of Mars. This volume is comparable to that of the Red Sea's water. Colin Wilson, an ESA project scientist, stated in a statement that "this latest analysis challenges our understanding of the Medusae Fossae Formation, and raises as many questions as answers." What conditions existed on Mars when these ice deposits formed, and how long ago did they form? These enormous deposits would alter our understanding of the climate history of Mars if they were indeed water ice. Any ancient water reserve would make an exciting target for robotic or human exploration.
Given that ice lies beneath the planet's current poles, the deposits might have formed when the poles were differently aligned in a previous epoch. Water would be essential to any future on Mars, even though accessing the deposits beneath all that dust would be challenging for a mission using current technology.