New evidence of life on Mars emerges

Analysis of data from the Curiosity rover has revealed that the Red Planet was once a river-laden world, providing a hospitable environment for life.

For almost half a decade, scientists have been exploring the footprints of water on Mars, finding various shreds of evidence.

A new discovery made by scientists from Pennsylvania State University reveals that craters on the surface of the planet, known as bench-and-nose landforms, were produced by rivers.

“We’re finding evidence that Mars was likely a planet of rivers,” said Benjamin Cardenas, assistant professor of geosciences at Penn State and lead scientist for the research. “We see signs of this all over the planet.”

Scientists, supported by NASA, have used computer models to simulate erosion on Mars’s surface over the millennia. The models were trained on satellite data, images made by the Curiosity rover, and 3D scans of layers of sedimentary bedrock, called strata, taken from the sea floor beneath the Gulf of Mexico by oil companies 25 years ago. These samples provided an ideal comparison to the surface of the Red Planet.

bed-and-nose landforms on Mars — Bench-and-slope morphology pictured on Mars and nose morphology from the ground at Mar's Mont Mercou outcrop. Credit: NASA/Caltech-JPL/MSSS

In previous research, scientists examined data from satellites orbiting Mars and noticed certain landforms on the planet's surface known as fluvial ridges. These fluvial ridges were considered to be potential indicators of ancient river deposits, suggesting that water might have flowed there in the past.

The new discovery by Pennsylvania State University’s scientists has challenged this theory. When they ran a simulation, the model revealed erosional landscapes shaped into topographic benches and noses, rather than fluvial ridges. The landforms closely resembled the ones observed by the Curiosity rover within the Gale Crater.

The discovery that bench-and-nose landforms are ancient riverbeds suggests that the planet could have even more undiscovered river deposits. According to scientists, river corridors are a crucial precondition for various life forms to thrive, providing an environment where chemical, nutrient, and sediment cycles take place.

“Our research indicates that Mars could have had far more rivers than previously believed, which certainly paints a more optimistic view of ancient life on Mars,” Cardenas said. “It offers a vision of Mars where most of the planet once had the right conditions for life.”

The study was published in Geophysical Research Letters.