New research reveals a surprising amount of water locked away on the red planet.
For decades, scientists have hypothesised about what may have occurred to all the water on Mars, which is considered to have been an essentially wetter planet aeons ago. Some water can be detected, frozen in the Martian polar ice caps, but new research shows there’s also a shocking amount of water on Mars. The finding could have a major impact on improving plans to harvest water for a future human presence on the red planet.
It’s been largely assumed that as Mars’ ancient atmosphere was slowly sucked out into space, much of its surface water went with it. However, a new NASA-backed study reveals a remarkable portion of all that Martian moisture is still on the planet, trapped in its crust.
According to a statement by Caltech PhD candidate Eva Scheller, atmospheric escape doesn’t fully elaborate the data that they have for how much water exactly once existed on Mars. Scheller is the lead author of the study published on Tuesday in the journal Science.
Scheller and his team looked at models that quantify the amount of water on Mars over time in various forms as well as present data on the chemical composition of the Martian atmosphere and the planet’s crust. They discovered that the atmospheric escape theory could not totally account for conditions seen today above and below the surface of our neighbouring world.
Bethany Ehlmann, CalTech professor of planetary science explains that atmospheric escape imminently had a role in water loss, but discoveries from the last decade of Mars missions have indicated the fact that there was this huge reservoir of ancient hydrated minerals whose formation definitely decreased water availability over time.
When water and rock communicate, a chemical weathering process can take place to create materials like clays that contain water within their mineral structure. This process happens on Earth, but the geological cycle ultimately sends moisture trapped in rocks back into the atmosphere through volcanism. But, Mars seems to have very little if any volcanic activity, leaving all that water stuck in the crust.
All of this water was separated quite early on, and then never cycled back out.
The team discovered that 4 billion years back, Mars had enough water to cover the entire planet with an ocean between 100 and 1,500 meters (328 and 4,920 feet) deep, and that between 30% and 99% of that water is now confined in minerals in the crust. Scheller and Ehlmann will assist the Mars 2020 Perseverance rover team in accumulating rock samples from Mars for final return and research here on Earth to test the theory.