The European Space Agency’s Mars Express Orbiter was responsible for the discovery. The Mars Express was launched in June of 2003 and has been used to research the fourth planet from the sun ever since 2004. Since that time it has found striking evidence of current or past presence of water on Mars including the discovery of hydrated minerals which, according to NASA, form only in the presence of water.  This is not the first time evidence of ice has been found on Mars, but the new discovery represents the largest potential deposits of ice found thus far in an area known as the Medusae Fossae Formation, which was studied about 15 years ago for its deposits which were not able to be clearly seen at the time.

  “We’ve explored the MFF again using newer data from Mars Express’s MARSIS radar, and found the deposits to be even thicker than we thought: up to 3.7 km thick,” said Thomas Watters of the Smithsonian Institution USA, lead author of both the new research and the initial 2007 study. “Excitingly, the radar signals match what we’d expect to see from layered ice, and are similar to the signals we see from Mars’s polar caps, which we know to be very ice rich.” The MFF is an area of Mars known for its massive amounts of dust which can create harrowing dust storms all around the planet.

When the Mars Express originally identified images of the deposits 15 years ago, it was suspected the deposits might just be more dust, but researchers have said that the new images show greater evidence that the deposits appear to be water ice.  “Here’s where the new radar data comes in! Given how deep it is, if the MFF was simply a giant pile of dust, we’d expect it to become compacted under its own weight,” said co-author Andrea Cicchetti of the National Institute for Astrophysics, Italy.

“This would create something far denser than what we actually see with MARSIS. And when we modeled how different ice-free materials would behave, nothing reproduced the properties of the MFF – we need ice.” The discovery was made from an orbiting spacecraft far above the surface so it will likely be several years, decades even, before we can find out for certain but the European Space Agency emphasized the importance of the discovery as crucial information to a well-rounded understanding of the planet which very well could house humans one day.

“This latest analysis challenges our understanding of the Medusae Fossae Formation, and raises as many questions as answers,” said Colin Wilson, ESA project scientist for Mars Express and the ESA ExoMars Trace Gas Orbiter (TGO). “Unfortunately, these MFF deposits are covered by hundreds of meters of dust, making them inaccessible for at least the next few decades. However, every bit of ice we find helps us build a better picture of where Mars’s water has flowed before, and where it can be found today.

” In the event that a human-occupied spacecraft lands on Mars, it’s near impossible with current technology to land near the polar caps of Mars, which have been known for a while to contain water ice. If the MFF deposits do turn out to be water ice, it would be a much easier area to access based on proximity to potential landing zones for humans to access water.  “How long ago did these ice deposits form, and what was Mars like at that time? If confirmed to be water ice, these massive deposits would change our understanding of Mars climate history.

Any reservoir of ancient water would be a fascinating target for human or robotic exploration,” Wilson said. “Together, our Mars explorers are revealing more and more about our planetary neighbor.” Read less