The study, conducted by University College London and published in Geology, identified more than 17,000 kilometers of ancient riverbeds located on a plain in the northern parts of the Red Planet called Arabia Terra, providing groundbreaking evidence that extensive water existed on Mars. “Climate models of early Mars predict rain in Arabia Terra and until now there was little geological evidence on the surface to support this theory. This led some to believe that Mars was never warm and wet but was a largely frozen planet, covered in ice sheets and glaciers. We’ve now found evidence of extensive river systems in the area which supports the idea that Mars was warm and wet, providing a more favorable environment for life than a cold, dry planet,” explained lead author, Joel Davis (UCL Earth Sciences).
However, these structures were not identified until researchers decided to analyze high-resolution images provided by NASA’s spacecraft the MRO.
The new study examined an area of land approximately the size of Brazil.
However, researchers examined the area with a never before resolution equaling 6 meters-per-pixel, compared to previous 100 meters-per-pixel.
In addition to a few valleys, the team revealed the existence of many systems of fossilized river beds visible as inverted channels spread across the Arabia Terra plain.
Interestingly, scientists say these channels ar eerily similar to those found on Earth and other parts of Mars.
Comparing the discovery to Earth, researchers say that on Earth, inverted channels often occur in dry, desert environments like Oman, Egypt.
“The networks of inverted channels in Arabia Terra are about 30 metres high and up to 1-2 kilometres wide, so we think they are probably the remains of giant rivers that flowed billions of years ago. Arabia Terra was essentially one massive floodplain bordering the highlands and lowlands of Mars. We think the rivers were active 3.9-3.7 billion years ago, but gradually dried up before being rapidly buried and protected for billions of years, potentially preserving any ancient biological material that might have been present,” added Joel Davis.
“These ancient Martian flood plains would be great places to explore to search for evidence of past life. In fact, one of these inverted channels called Aram Dorsum is a candidate landing site for the European Space Agency’s ExoMars Rover mission, which will launch in 2020,” said Dr. Matthew Balme, Senior Lecturer at The Open University and co-author of the study.