Out of Pebble Purgatory
Mars Perseverance Sol 330 - WATSON Camera: NASA's Mars Perseverance rover acquired this image using its SHERLOC WATSON camera, located on the turret at the end of the rover's robotic arm. This image was acquired on Jan. 23, 2022 (Sol 330) at the local mean solar time of 16:50:41. Credits: NASA/JPL-Caltech. Download image ›

The final two pebbles hitching a ride aboard our rover’s bit carousel are gone but not forgotten. I’ll give you the latest on why they are gone and then tell you why we are not forgetting them – or the two other pebbles that made our first month of 2022 a busy one.


We had more than a suspicion the rocks had departed the Perseverance rover on Sunday when imagery of the bit carousel came down after a short 16-foot (5 meter) drive to a nearby rocky outcrop. That drive, which took place on the previous sol, was designed to get us to a small rocky outcrop that would place the rover at an angle that could be beneficial for ejecting the pebbles.

To be thorough (because we Mars missions like to be), we did a full rotation of the bit carousel in both directions, with the rover oriented in a 13.2-degree roll to the left, and we found nothing hindering its progress. We also ran the rover’s percussion drill to induce vibration, hoping to shake any possible remaining debris free from the bit holder. Finally, we docked the drill to the bit carousel and dropped off the bit.

With this last step we are happy to announce our sampling system is up and running and ready to go, which is a good thing, since we’re going to use it right away. The science team wants another sample from the rock they call “Issole,” so we drove the 16 feet (5 meters) back and are now in the process of collecting one. Our Twitter feed @NASAPersevere will update you on that progress.

Perseverance Playbook

As you know, Perseverance is the first sample caching mission on the Red Planet. We did a great deal of testing before we got there, but Mars is Mars. The place is cold, unpaved, far away (about 205 million miles [330 million km] today), and with unexplored, sometimes uncooperative stuff over every hill and around just about every boulder. And that lack of cooperation sometimes extends to the rocks our science team wants to sample.

Those of you who have been following us – and we appreciate it! – know that our first attempt to core a rock was less than satisfying, with the sample crumbling before we could collect it. But we learned a lot from rock target “Roubion,”and we modified our playbook to understand better how to collect samples – and from which rocks. This new “pebbles in bit carousel” affair has also allowed us to make additions to our sampling playbook. If we encounter a similar scenario down the Martian road, we should be able to get back on track more quickly – which is good, because Jezero Crater is simply amazing and I can’t wait to see what awaits us on the other side of the next hill.

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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