In a striking discovery on Mars, NASA’s Perseverance rover has captured images of a mysterious black-and-white striped rock, unlike any seen before on the Red Planet. Dubbed “Freya Castle,” the rock was found in the Jezero Crater, a dried ancient lakebed that Perseverance has been exploring since its landing in February 2021.
A Striped Mystery in Jezero Crater
The so-called Freya Castle, a small rock measuring just 8 inches (20 centimeters) across, appears out of place on Mars. Its bold black-and-white pattern stands in sharp contrast to the rust-colored Martian landscape. Early hypotheses suggest that the rock’s unique texture could be the result of igneous processes, where magma crystallizes, and metamorphic changes, where rocks are transformed by high heat and pressure. These patterns can emerge when light-colored quartz and dark-colored basalt are layered together.
But there’s much more to learn.
NASA scientists believe Freya Castle might have originated elsewhere, perhaps rolling down from higher up the Jezero Crater. The rock is loose and differs from the surrounding bedrock, which adds strength to the idea that it traveled from a distant location. “This possibility has us excited,” NASA noted in a statement, expressing hope that Perseverance’s ongoing ascent up the crater will lead to more such discoveries.
The find is one of several intriguing rock formations Perseverance has documented in recent months. Earlier this year, the rover captured images of a light-colored boulder near Mount Washburn and another rock with leopard-like spots, which could provide valuable clues about ancient life on Mars.
Climbing the Crater Rim
Freya Castle’s discovery comes at a pivotal time for Perseverance. The rover is currently en route to its first major crater rim study at a site called Dox Castle. Located on the western edge of Jezero Crater, Dox Castle may contain rocks scattered by the asteroid impact that originally carved the crater billions of years ago.
These ancient rocks could hold critical insights into Mars’ past. Scientists believe the heat from the asteroid impact may have triggered fluid movement through fractures, much like the hydrothermal vents found on Earth’s ocean floors. These environments, rich with chemical energy, could be instrumental in understanding how life emerged — both on Earth and possibly on Mars. “With the Perseverance rover, we have the potential to explore some of the oldest exposed rocks on the planet,” said Margaret Deahn, a researcher from Indiana’s Purdue University involved with mapping Perseverance’s journey.
The rover’s climb to Dox Castle, part of a broader mission called the Crater Rim Campaign, represents one of its most challenging maneuvers yet. Since mid-August, Perseverance has been navigating rocky slopes as steep as 23 degrees, climbing nearly 1,000 feet (300 meters) in total. Despite a regional dust storm that obscured its view in late August, Perseverance has continued its steady ascent on its own without human piloting from NASA mission control, thanks to its automatic navigation system, AutoNav.
What Lies Ahead?
As Perseverance inches closer to Dox Castle, scientists are eager to study the ancient rocks that could help unlock Mars’ geological history. The rover is also collecting samples that NASA hopes to bring back to Earth through its ambitious Mars Sample Return mission, a collaborative effort with the European Space Agency. Perseverance has already deposited a backup collection of samples on the crater floor, awaiting future retrieval.
But the mission is far from over. The Crater Rim Campaign will allow scientists to study new rock formations that could contain evidence of ancient microbial life, preserved for billions of years. “Our rover is in excellent condition, and the team is raring to see what’s on the roof of this place,” said Art Thompson, Perseverance’s project manager.
With each new discovery, from the zebra-striped Freya Castle to the ancient rocks of Dox Castle, Perseverance continues to reshape our understanding of Mars. As the rover climbs higher, the Martian skies may soon clear, offering breathtaking views of the crater floor and delta — along with new, tantalizing questions about Mars’ past and its potential to harbor life.
