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Searching for the Dark in the Light

A color close-up photo of the Martian surface shows a pale tan-orange rock, with a more or less circular face showing, that has grooves or lines emanating from a center point like rays.
The Perseverance rover acquired this image of the “Hare Bay” abrasion patch using its SHERLOC WATSON camera (Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals, and the Wide Angle Topographic Sensor for Operations and eNgineering), located on the turret at the end of the rover’s robotic arm. This image was acquired on April 18, 2025 (Sol 1479, or Martian day 1,479 of the Mars 2020 mission) at the local mean solar time of 12:53:57.
NASA/JPL-Caltech

Written by Eleanor Moreland, Ph.D. Student Collaborator at Rice University 

Perseverance has been busy exploring lower “Witch Hazel Hill,” an outcrop exposed on the edge of the Jezero crater rim. The outcrop is composed of alternating light and dark layers, and naturally, the team has been trying to understand the makeup of and relationships between the light and dark layers. A few weeks ago, we sampled one of the light-toned layers, which we discovered was made up of very small clasts, or fragments of rocks or minerals, at “Main River.” Since then, we have learned that the dark layers tend to be composed of larger clasts compared to the light layers, and we’ve been searching for a place to sample this coarser-grained rock type. Sometimes, these coarser-grained rocks also contain spherules, which are of great interest to the science team because they provide clues about the process that formed these layered rocks.

Perseverance first looked at a dark layer at “Puncheon Rock” with an abrasion. We then examined a dark layer at “Wreck Apple,” near “Sally’s Cove,” but we could not identify a suitable surface to abrade. So, while team members searched for other locations to study the coarse-grained units and spherules, Perseverance drove south to “Port Anson.”

A color photo from the Mars surface shows pale orange, gritty terrain with lighter-colored flat rocks visible above the soil in several areas. At the image center, the Perseverance rover’s mechanical arm, with a boxy instrument at its end, extends from beyond the top of the frame and reaches toward the ground. Its shadow runs along the ground from the center of the frame to the lower left corner of the image. Shadowed portions of the rover are visible along the top of the image frame, and the lower-right corner, while a rover wheel is visible in the lower left.
Perseverance acquired this image of the “Strong Island” workspace near Port Anson using its onboard Front Left Hazard Avoidance Camera A (https://science.nasa.gov/mission/mars-2020-perseverance/rover-components/#eyes). This image was acquired on April 12, 2025 (Sol 1473, or Martian day 1,473 of the Mars 2020 mission) at the local mean solar time of 12:50:32.
NASA/JPL-Caltech

Port Anson was intriguing because, from orbit, it showed a clear contact between the light layers of Witch Hazel Hill and a distinct unit below it. And, although the rocks below the Port Anson contact do show interesting compositional differences with those of Witch Hazel Hill, they weren’t the coarse-grained rocks we were looking for. We still performed an abrasion there, at Strong Island, before driving back up north for another attempt at investigating the coarser-grained rocks.

We aimed for “Pine Pond,” which neighbors “Dennis Pond,” to abrade at “Hare Bay.” With the data just coming down over the weekend, the team will be hard at work to figure out if we captured the coarse grains and spherules, and if it is representative of rocks we have seen before or not. The image below is a close-up of this most recent abrasion patch at Hare Bay — what do you think? Stay tuned to find out! 

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Apr 25, 2025

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      Searching for Ancient Rocks in the ‘Forlandet’ Flats
      NASA’s Mars Perseverance rover acquired this image of the “Fallbreen” workspace using its onboard Left Navigation Camera (Navcam). The camera is located high on the rover’s mast and aids in driving. This image was acquired on May 22, 2025 (Sol 1512, or Martian day 1,512 of the Mars 2020 mission) at the local mean solar time of 14:39:01. NASA/JPL-Caltech Written by Henry Manelski, Ph.D. student at Purdue University
      This week Perseverance continued its gradual descent into the relatively flat terrain outside of Jezero Crater. In this area, the science team expects to find rocks that could be among the oldest ever observed by the Perseverance rover — and perhaps any rover to have explored the surface of Mars — presenting a unique opportunity to understand Mars’ ancient past. Perseverance is now parked at “Fallbreen,” a light-toned bedrock exposure that the science team hopes to compare to the nearby olivine-bearing outcrop at “Copper Cove.” This could be a glimpse of the geologic unit rich in olivine and carbonate that stretches hundreds of kilometers to the west of Jezero Crater. Gaining insight into how these rocks formed could have profound implications for our constantly evolving knowledge of this region’s history. Perseverance’s recent traverses marked another notable transition. After rolling past Copper Cove, Perseverance entered the “Forlandet” quadrangle, a 1.2-square-kilometer (about 0.46 square mile, or 297-acre) area along the edge of the crater that the science team named after Forlandet National Park on the Norwegian archipelago of Svalbard. Discovered in the late 16th century by Dutch explorers, this icy set of islands captured the imagination of a generation of sailors searching for the Northwest Passage. While Perseverance is in the Forlandet quad, landforms and rock targets will be named informally after sites in and around this national park on Earth. As the rover navigates through its own narrow passes in the spirit of discovery, driving around sand dunes and breezing past buttes, we hope it channels the perseverance of the explorers who once gave these rocks their names.
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