Persevering Across the Upper Fan in Search of Record-Keeping Rocks
A Crumbly Conglomerate: This image of the Ouzel Falls abrasion patch was taken by Perseverance’s WATSON camera on Sol 799 (May 20, 2023), revealing an array of pebbly clasts in a soft, crumbly matrix. Credits: NASA/JPL-Caltech. Download image ›

Sampling Martian rocks requires persistence! Right now, Perseverance is on the hunt for a conglomerate rock to sample for return to Earth – a task that is proving to be challenging. Two attempts were made to core at the Onahu outcrop, but the soft rock crumbled during each attempt. The team set sights on a neighboring outcrop called Stone Man Pass, about 40 meters away, to search for a less crumbly conglomerate that could stand up to the coring process. After nearing Stone Man Pass, rover cameras indicated the rock is not a conglomerate, so instead, Perseverance drove to Emerald Lake, an outcrop a few tens of meters away and within the same layer as Onahu, to attempt sampling here.

What’s the deal with conglomerates and why is the team so interested in collecting one? Conglomerates are a type of sedimentary rock made up of rounded pebble-sized grains greater than 2 mm across, cemented together in a matrix of finer-grained minerals, mud, or sand. Conglomerates are important because they provide a window into the past, recording information about a variety of geologic events and environmental shifts. Minerals in each grain are evidence of geology and composition of source terrains, grain size and roundness bear witness to erosional processes that shaped and transported pebbles, and matrix makeup can provide information about the chemistry, pH, and redox state of fluids that infilled space between clasts after they were deposited. Additionally, these types of rocks can help complete the “conglomerate test,” a paleomagnetic tool used by geochronologists to date magnetization events in a planet’s past. Certain types of iron-bearing minerals display magnetic properties, and when a magnetic field is applied to these minerals, the direction of magnetization can shift, serving as a record of the event. The conglomerate test is used to determine whether a rock experienced a “remagnetization” event after it formed. Why does this matter? The conglomerate test can help determine when the Martian magnetic field was active. A planet’s magnetosphere, or global magnetic field, is the result of interactions between convection within a molten iron-rich core and the planet’s rotation on its axis. A magnetosphere is important for habitability, because it provides a shield against radiation from the Sun and deep space and can help a planet retain its atmosphere. In the past, Mars had a molten core and magnetosphere, but at some point in history the core cooled and began to solidify, causing the magnetic field to shut off. Scientists believe that this may be why the Martian atmosphere is thinner today: absent a magnetic field to protect from radiation, solar wind can reach the surface and strip the atmosphere away to space. Returned samples will help test this hypothesis! Determining when this process occurred is an important goal for planetary scientists and astrobiologists seeking to understand Mars’ geologic past and changing habitability. With these goals in mind, Perseverance will continue to work towards collecting a conglomerate sample from the upper fan, so back on Earth, scientists can apply the conglomerate test to this special core and better constrain Mars’ paleomagnetic past.

About This Blog

These blog updates are provided by self-selected Mars 2020 mission team members who love to share what Perseverance is doing with the public.

Dates of planned rover activities described in these blogs are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.

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  • Mariah Baker
    Planetary Scientist, Smithsonian National Air & Space Museum
    Washington, DC
  • Matthew Brand
    SuperCam/ChemCam Engineer, Los Alamos National LaboratoryLos Alamos National Laboratory
  • Sawyer Brooks
    Docking Systems Engineer, NASA/JPL
    Pasadena, CA
  • Adrian Brown
    Deputy Program Scientist, NASA HQ
    Washington, DC
  • Denise Buckner
    Student Collaborator, University of Florida
    Gainesville, FL
  • Fred Calef III
    Mapping Specialist, NASA/JPL
    Pasadena, CA
  • Stephanie Connell
    SuperCam, PhD Student, Purdue University
    West Lafayette, IN
  • Alyssa Deardorff
    Systems Engineer, NASA/JPL
    Pasadena, CA
  • Kenneth Farley
    Project Scientist, Caltech
    Pasadena, CA
  • Phylindia Gant
    Mars 2020 Student Collaborator, University of Florida
    Gainesville, FL
  • Brad Garczynski
    Student Collaborator, Purdue University
    West Lafayette, IN
  • Erin Gibbons
    Student Collaborator, McGill University
    Montreal, Canada
  • Michael Hecht
    Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) Principal Investigator, Massachusetts Institute of Technology
    Westford, MA
  • Louise Jandura
    Chief Engineer for Sampling & Caching, NASA/JPL
    Pasadena, CA
  • Elisha Jhoti
    Ph.D. Student, University of California, Los Angeles
    Los Angeles, CA
  • Bavani Kathir
    Student Collaborator on Mastcam-Z, Western Washington University
  • Lydia Kivrak
    Student Collaborator, University of Florida
    Gainesville, FL
  • Athanasios Klidaras
    Ph.D. Student, Purdue University
  • Rachel Kronyak
    Systems Engineer, NASA/JPL
    Pasadena, CA
  • Steven Lee
    Perseverance Deputy Project Manager, NASA/JPL
    Pasadena, CA
  • An Li
    Student Collaborator on PIXL, University of Washington
  • Justin Maki
    Imaging Scientist and Mastcam-Z Deputy Principal Investigator, NASA/JPL
  • Forrest Meyen
    MOXIE Science Team Member, Lunar Outpost
  • Sarah Milkovich
    Assistant Science Manager, NASA/JPL
    Pasadena, CA
  • Eleanor Moreland
    Ph.D. Student, Rice University
    Houston, Texas
  • Asier Munguira
    Ph.D. Student, University of the Basque Country
  • Matt Muszynski
    Vehicle Systems Engineer, NASA/JPL
    Pasadena, CA
  • Claire Newman
    Atmospheric Scientist, Aeolis Research
    Altadena, CA
  • Avi Okon
    Sampling Operations Deputy Lead, NASA/JPL
    Pasadena, CA
  • Pegah Pashai
    Vehicle Systems Engineer Lead, NASA/JPL
    Pasadena, CA
  • David Pedersen
    Co-Investigator, PIXL Instrument, Technical University of Denmark (DTU)
    Copenhagen, Denmark
  • Eleni Ravanis
    Student Collaborator, University of Hawaiʻi at Mānoa
    Honolulu, HI
  • Thirupathi Srinivasan
    Robotic Systems Engineer, NASA/JPL
  • Kathryn Stack
    Deputy Project Scientist, NASA/JPL
    Pasadena, CA
  • Vivian Sun
    Science Operations Systems Engineer, Staff Scientist, NASA/JPL
    Pasadena, CA
  • Iona (Brockie) Tirona
    Sampling Engineer, NASA/JPL
    Pasadena, CA
  • Jennifer Trosper
    Project Manager, NASA/JPL
    Pasadena, CA
  • Vandi Verma
    Chief Engineer for Robotic Operations, NASA/JPL
    Pasadena, CA
  • Rick Welch
    Deputy Project Manager, NASA/JPL
    Pasadena, CA
  • Roger Wiens
    Principal Investigator, SuperCam / Co-Investigator, SHERLOC instrument, Purdue University
    West Lafayette, IN

Tools on the Perseverance Rover+

The Perseverance rover has tools to study the history of its landing site, seek signs of ancient life, collect rock and soil samples, and help prepare for human exploration of Mars. The rover carries:


Where is the Rover?

Image of a rover pin-point at Perseverance's location on Mars, Jezero Crater

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