The landscapes of Mount Sharp indicate that rivers, lakes and groundwater were present over millions of years.
The discovery is based on data collected by Curiosity over the past 2.5 years, including findings of sediment beds of sandstones that are inclined toward Mount Sharp, a three-mile high mound rising from the center of a 96-mile wide impact crater.
“We can see a whole series of beds, of sandstones, with some pebble beds in there, that are actually inclined at a large scale toward the south,” Curiosity scientist Sanjeev Gupta, with Imperial College in London, told reporters on a conference call.
To get a long-lived lake in Gale Crater there must have been so much water in the climate system that the frozen latitudes were essentially filled up, that water was forced to warmer latitudes where it would exist as liquid.
Scientists believe that means that not only did Mount Sharp not exist at the time, but that Curiosity’s Gale Crater landing site was once — and possibly many times over — a shallow lake.
Similar inclined beds are found on Earth at the mouths of river channels where they feed into lakes, Gupta said.
The question is crucial to understanding how long Mars may have had conditions suitable for life to evolve.