NASA’s hunt for life on Mars is far from over: its rover has found evidence of an ancient lake that may have been home to microbial life.
The Perseverance rover examined the Jezero crater, where it identified sediments deposited by water, confirming speculation that the formation flowed with water three billion years ago.
The car-sized, six-wheeled machine captured images of the crater, allowing scientists to see a cross-section of rock layers at a depth of 65 feet (20 meters) that was “almost like looking at a cut-away road.”
The findings reinforce what previous studies have long suggested: that cold, arid, lifeless Mars was once warm, wet and perhaps habitable.
The Perseverance rover examined the Jezero crater (pictured), where it identified sediments deposited by water, confirming speculation that the formation flowed with water three billion years ago
Scientists chose the Jezero crater for the rover’s mission because they had previously found water-rich minerals in the basin
The Mars Reconnaissance Orbiter, which orbits the Red Planet, also revealed that the crater contains clay, which only forms in the presence of water.’
However, the team said that recent evidence from Perseverance shows that water was flowing into the basin.
The findings were discovered using Perseverance’s instrument, which fires radar waves beneath the surface of Mars at 10 centimeter intervals and measures pulses reflected from depths of about 20 meters below the surface.
Scientists were able to see deep into the sediments and found two different periods of sediment deposition in the middle of two periods of erosion.
The findings were discovered using Perseverance’s instrument, which fires radar waves (black and white) beneath the surface of Mars at 10 centimeter intervals and measures pulses reflected from depths of about 20 meters below the surface.
The team from the University of California (UC)-Los Angeles and Norway’s Olso University noted that the crater floor beneath the delta was not uniformly flat, which could only mean that erosion by water had occurred before the deposition of lake sediments.
‘The radar images show that the sediments are regular and horizontal, just like sediments deposited in lakes on Earth. The existence of lake sediments was suspected in previous studies but has been confirmed by this study,” the researchers shared in the announcement.
A second period of deposition occurred when fluctuations in lake levels caused the river to deposit a wide delta that once extended well into the lake but has now been eroded closer to the river’s mouth.
First author David Paige, professor of Earth at UCLA, said: ‘The changes we see preserved in the rocks are caused by large-scale changes in the Martian environment.
“It’s cool that we can see so much evidence of change in such a small geographic area, allowing us to extend our findings to the scale of the entire crater.”
Scientists chose the Jezero crater for the rover’s mission because they had previously found water-rich minerals in the basin
Perseverance launched on July 30, 2020 with the Ingenuity helicopter as its companion. Perseverance landed at the foot of Jezero on February 18, 2021, with a mission to find ancient signs of life in the 250-meter-deep crater.
The discovery was made as Perseverance traveled over the crater floor between May 10 and December 8, 2022.
The rover was headed toward an adjacent expanse of braided, sedimentary features that, from orbit, resembled Earth’s river deltas.
“From Earth orbit we can see a lot of different deposits, but we can’t say for sure whether what we’re seeing is their original state, or whether we’re seeing the conclusion of a long geological story,” Page said of the Mars orbiter hovering over the Martian world.
“To tell how these things came to be, we have to look beneath the surface.”
Perseverance launched on July 30, 2020 with the Ingenuity helicopter as its travel companion.
Perseverance landed at the foot of Jezero on February 18, 2021, with a mission to find ancient signs of life in the 250-meter-deep crater.
While the rover is still very much alive, Ingenuity is now sitting in the dusty landscape after an accident that damaged ‘one or more’ blades.
The small helicopter took off on January 18, but lost contact with the command team and when communications were restored, one of the craft’s blades showed damage.
Ingenuity was originally designed to conduct up to five experimental test flights over 30 days when it first landed in 2023.
But the helicopter, which cost $85 million, exceeded expectations with 72 flights and flew more than 14 times further than planned, while recording a total of more than two hours of flight time.
Data showed the helicopter reached a maximum height of 12 meters and hovered for 4.5 seconds before beginning its descent at a speed of 3.3 meters per second during its final fatal flight.