NASA’s Perseverance Rover has left Mount Washburn behind and arrived at its next destination, Bright Angel.
An unusual type of rock was found there that scientists call ‘popcorn rock’. The strange rock is evidence that water was once present in the Jezero crater.
Perseverance’s mission is focused on life on ancient Mars. In addition to searching for fossilized evidence of ancient life, it also searches and attempts to understand environments that could have supported life.
Therefore, it is located in the Jezero Crater, an ancient paleola lake with a delta of sediments and other intriguing geological features.
On Sol 1175 of its mission, Perseverance arrived at Bright Angel, a scientifically interesting region that is part of the river channel that drained into the Jezero Crater.
Bright Angel is known for its light-colored rock outcrops that are either ancient sediments that filled the canal or much older rock exposed by the river.
The image below shows the rover’s path leading to Bright Angel. The white section shows where Perseverance paralleled the Neretva Vallis river channel, and the blue section shows where it traveled through the channel.
The light-colored rocks of Bright Angel are clearly visible.
As Perseverance made its way toward Bright Angel, mission personnel could see the bright rocks in the distance. But the route to the new destination was not easy. The rover encountered a field of boulders that turned out to be so heavy that the operators changed course.
“We started paralleling the channel in late January and were making pretty good progress, but then the boulders got bigger and more numerous,” said Evan Graser, Perseverance’s deputy chief strategic route planner at NASA’s Jet Propulsion Laboratory in Southern California.
“What used to be an average of more than a hundred meters per Martian day dropped to just tens of meters. It was frustrating.”
Perseverance has two modes of travel. In more rugged terrain, the route planning team uses images to plan the rover’s route about 30 meters at a time. To travel further in a single sol, the team relies on Perseverance’s autopilot mode, called AutoNav.
But as the route through the boulder field became more difficult, AutoNav began to struggle. Sometimes it just stopped, which is the safest option. But that means the drive to Bright Angel took much longer than expected.
“We had been checking out the river channel just to the north as we were traveling, 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. .
“Perseverance also needed a ramp where we could get down safely. When the footage showed both, we headed down there.”
The rover was diverted through the dune field and over the river channel, shortening the journey by several weeks.
Perseverance is nearing the end of its fourth science phase. Carbonate rocks and olivine are being sought in the Margin Unit, which is located along the inner rim of Jezero Crater. But at Bright Angel it hoped to find other rocks.
That’s exactly what happened.
According to a NASA press release, geologists were mesmerized by what they saw. Some rocks are densely packed with spheres, giving them the name “popcorn rocks.”
The rocks are also full of ridges that resemble mineral veins. Mineral veins form when water transports and deposits minerals through rock.
Mineral veins are common on wet, watery Earth, and rovers have spotted them elsewhere on Mars.
The popcorn characteristics may also be evidence of water. Like the mineral veins, they indicate that water flowed through these rocks.
The next step is to determine what minerals are present in these popcorn rocks. Perseverance will work its way to Bright Angel as he takes measurements.
Over the weekend he will use his sanding tools and other instruments to take an even closer look. It will vaporize some of the rock and use its SuperCam instrumentation to examine the rock’s chemistry.
The decision to take a sample for the eventual return to Earth (hopefully) will rest on those results.
Once Perseverance is completed at Bright Angel, the rover will travel south again, over Neretva Vallis, to its next destination: Serpentine Rapids.
This article was originally published by Universe Today. Read the original article.