Throwback to the Little 'Mushroom'
Mars Perseverance Sol 467 - Left Mastcam-Z Camera: This image of a mushroom-shaped rock feature (top left) was acquired on June 13, 2022 (Sol 467) at the local mean solar time of 13:00:39 using the Mastcam-Z instrument. Credits: NASA/JPL-Caltech/ASU. Download image ›

Back in 2022, Perseverance found my favourite rock on the mission so far: a flat piece with a mushroom-shaped rock feature sticking out of it! The “mushroom” is about 1-2 cm tall and less than 1 cm wide. The rock was in an area the rover explored called Hogwallow Flats. Many aspects of Hogwallow Flats set it apart from the rest of the rocks in Jezero: it was very fine-grained compared to other units, it contained a higher proportion of sulfate salts, and it had interesting rock features like the “mushroom” within it.

The “mushroom” is actually a geologic feature known as a concretion. Concretions are solid masses within a rock that form as water flows through sediment, dissolving minerals and reprecipitating them in a more compacted configuration. Concretions are usually harder than the surrounding rock, making them less vulnerable to erosion and weathering. On Earth, concretions come in a wide variety of shapes (spherical to irregular) and sizes (1 mm to 2.2 meters) and they first appear in the terrestrial rock record over 3 billion years ago. We do not know when the “mushroom” concretion at Hogwallow Flats was first formed but as wind carved out the surface of Mars over billions of years, it eroded the softer bedrock around this hard concretion. Now all that’s left of the surrounding bedrock is a very thin rock spire connecting the concretion to the flat rock below, like a miniature version of the giant hoodoo features of the American southwest. Near this interesting feature, we also saw big, disc-shaped concretions, small, spherical concretions, and pointy concretions! It was an exciting summer, full of a variety of concretion shapes. The rover cored a sample from Hogwallow Flats called ‘Bearwallow’ that may contain a concretion so if the samples are returned to Earth, we will be able to learn even more about martian concretions and how they were formed! Another interestingly wind carved martian rock is this ‘spoon’ shaped rock captured by Curiosity rover in 2015.

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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