Fine-Grained Rocks at Hogwallow Flats
Mars Perseverance Sol 472 - Left Mastcam-Z Camera: Perseverance rover acquired this image using its Left Mastcam-Z camera. Mastcam-Z is a pair of cameras located high on the rover’s mast. This image was acquired on June 18, 2022 (Sol 472). Credits: NASA/JPL-Caltech/ASU. Download image ›

Perseverance’s exploration of the Hawksbill Gap area of the Jezero Delta continues!  The rover has abraded at two different locations over the last few weeks.  First, the rover abraded in the Devil’s Tanyard area.  Unfortunately, the crumbly rocks at Devils Tanyard were broken and moved by the force of the abrasion. Nevertheless, the team was able to use the SuperCam and Mastcam-Z instruments to gather valuable scientific data of the abrasion patch and surrounding area.

The rover then made its way up the delta to abrade at Hogwallow Flats, an area nicknamed “the Bacon Strip” by the team due to its light-colored striped rocks, which look like a strip of bacon in images taken by the Hi-Rise orbiter.  The rocks at Hogwallow Flats appear to be very fine-grained, which is exciting to scientists on the mission as fine-grained rocks may have the best chance at preserving evidence of life.  In order to understand why, we need to talk a little about organic molecules. 

Molecules made up of mostly carbon, hydrogen, and oxygen are called organic molecules and are the primary building blocks of life on Earth. Some small organic molecules can be produced without the presence of life (and have been detected on Mars and in meteorites in the past), so the presence of organic molecules in a rock does not automatically mean that life was present.  However, the detection of particularly large and complex organic molecules, or specific patterns of organic molecules, could be considered a biosignature.  Unfortunately, large and complex molecules break down into smaller ones over time due to radiation from the sun and reactions with the rocks and atmosphere.  If there was life in Jezero crater 3-4 billion years ago, most of the large organic molecules created by it would have been destroyed, leaving little evidence of the presence of life.  

In order to have a chance of detecting evidence of life in the samples that Perseverance will ultimately send back, we need to sample rocks that have the best chance of preserving complex organic molecules – fine-grained rocks.  This is because fine-grained rocks are more likely to contain large amounts of clay minerals than rocks with lots of sand, pebbles, and gravel.  Clay minerals have charged surfaces that can bind to organic molecules, kind of like how magnets with opposite charges stick together.  By being attached to clay minerals in this way, complex organic molecules can be protected from damage in the harsh Martian environment, and preserved over a much longer period of time then they would be otherwise.

The team plans for Perseverance to explore several more sites on the delta front before deciding where it will sample. We will continue to keep an eye out for more fine-grained rocks as we continue on from Hogwallow!

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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