NASA’s persistence crosses an ancient river to achieve the scientific objective

Originally thought of as little more than a road without rocks slowing the rover, Neretva Vallis has offered a wealth of geological options for the science team.

After swerving across a dune field to avoid rocks that rattle the wheels, NASA’s Mars Perseverance rover reached its latest area of ​​scientific interest on June 9. The route change not only cut the estimated travel time to reach the area – nicknamed the “Bright Angel” – by several weeks, but also gave the science team an opportunity to find exciting geological features in a river channel of ancient.

The persistence is in the later stages of its fourth science campaign, looking for evidence of carbonate and olivine deposits in the Margin Unit, an area along the interior of the Jezero crater rim. Located at the base of the northern channel wall, Bright Angel contains light-hued rock outcrops that may represent either ancient rocks exposed by river erosion or sediments that filled the channel. The team hopes to find rocks different from those in the Margin Unit rich in carbonates and olivine and gather more data about the history of Jezero.

To reach Bright Angel, the rover passed a ridge along the channel of the Neretva Vallis river, which billions of years ago carried a large amount of water that poured into the Jezero crater. “We started aligning the duct at the end of January and were making pretty good progress, but then the boulders got bigger and more numerous,” said Evan Graser, deputy director of Persistence Path strategic planner at the Jet Propulsion Laboratory. of NASA in Southern California. “What had been paddling averaging over a hundred meters a Martian day dropped to just tens of meters. It was disappointing.”

In rough terrain, Evan and his team use the rover’s images to plan trips about 100 feet (30 meters) at a time. To get farther on any given Martian day or days, planners rely on Perseverance’s automatic navigation system, or AutoNav, to take over. But as the rocks became more numerous, the AutoNav would, more often than not, determine that the walk was not to its liking and stop, dimming the prospects of a timely arrival at Bright Angel. Still, the team had hope, knowing they could find success cutting a quarter-mile (400-meter) dune field into the river channel.

“We had looked at the river channel just to the north as we went, hoping to find a section where the dunes were small and far enough apart for a rover to pass between them — because dunes are known to eat Mars rovers,” Graser said. . . “The stand also needed an access ramp that we could safely travel down. When the images showed both, we made a beeline for it.”

The Persistence science team was also eager to travel through the ancient river channel because they wanted to investigate ancient Martian river processes.

With AutoNav’s help guiding the route on the canal floor, Perseverance covered the 656 feet (200 meters) to the first science stop on a sol. The target: Mount Washburn, a hill covered in intriguing rocks, some of a kind not previously seen on Mars.

“The diversity of textures and compositions at Mount Washburn was an exciting discovery for the team, as these rocks represent a grab bag of geologic bounty brought down from the crater rim and potentially beyond,” said Brad Garczynski of Western Washington University in Bellingham. co-leader of the current scientific campaign. “But among all these different rocks, there was one that really caught our attention.” They called it “Atoko Point”.

About 18 inches (45 centimeters) wide and 14 inches (35 centimeters) tall, the speckled, light-hued stone stands out against a field of darker stones. Analysis by Perseverance’s SuperCam and Mastcam-Z instruments shows that the rock is composed of the minerals pyroxene and feldspar. In terms of the size, shape and arrangement of its mineral grains and crystals – and potentially its chemical composition – Atoko Point is in a league of its own.

Some Perseverance scientists speculate that the minerals that make up Atoko Point were produced in an underground body of magma that is probably now exposed on the crater rim. Others on the team wonder if the stone was created far beyond Lake Jezero’s walls and carried there by swift Martian waters centuries ago. Either way, the team believes that while Atoko is the first of its kind they’ve seen, it won’t be the last.

After leaving Mount Washburn, the rover headed 433 feet (132 meters) north to investigate the geology of Tuff Cliff before making the four-sol, 1,985-foot (605-meter) trip to Bright Angel. Perseverance is currently analyzing a rock outcrop to assess whether a rock core sample should be collected.

A key objective for the Perseverance mission to Mars is astrobiology, including the preservation of samples that may contain signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and preserve Martian rock and regolith.

Subsequent NASA missions, in collaboration with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 Perseverance mission is part of NASA’s lunar exploration approach to Mars, which includes the Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.

NASA’s Jet Propulsion Laboratory, which is managed for the agency by Caltech, built and manages the operations of the Perseverance rover.

For more on Persistence:

DC Eagle
Jet Propulsion Laboratory, Pasadena, California.

Karen Fox / Charles Blue
NASA Headquarters, Washington
301-286-6284 / 202-802-5345 /


Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top