Element-ary, My Dear WATSON
Mars Is Infinitely Stranger Than Anything Which the Mind of Man Could Invent: This image of the Solva abrasion patch was taken by WATSON on Sol 781 (May 2, 2023), the sol before SHERLOC performed spectroscopy measurements over several regions within the patch. Credits: NASA/JPL-Caltech. Download image ›

When it comes to searching for clues about Mars’ geologic past and present, SHERLOC and WATSON are on the case! SHERLOC stands for Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals, and WATSON stands for Wide Angle Topographic Sensor for Operations and eNgineering. SHERLOC and WATSON both sit at the end of Perseverance’s robotic arm, and their names pay homage to the detective work these complementary instruments carry out on Mars as they scan and image rocks up close to query their composition.

SHERLOC is made up of a laser that zaps rocks, spectrometers that detect minerals and organic molecules by measuring laser-rock interactions, and a camera to take images of the scan regions so scientists can identify correlations between rock textures and compositions. WATSON is a camera modeled after the MAHLI (Mars Hand Lens Imager) camera onboard the Curiosity rover, and it takes close-range images (you can find them at this link by selecting “SHERLOC – WATSON” under “Science Cameras” in the panel on the right side of the page) that help rover operators decide exactly where to point SHERLOC so scientists can target visually-interesting areas of rock to scan, while avoiding topographically-challenging surfaces that could prove problematic for instrument placement. In addition to snapping pictures of rock targets before and after SHERLOC runs, WATSON plays an important role in helping the team choose exactly where to place the rover’s drill to sample, documenting the coring process, and providing support for other rover instruments like PIXL (Planetary Instrument for X-ray Lithochemistry), MOXIE (Mars Oxygen In-Situ Resource Utilization Experiment), and SuperCam.

To date, SHERLOC and WATSON have scanned every rock and regolith target where cores were drilled for return to Earth, in addition to performing analyses at several standalone locations along the rover’s traverse. By querying mineralogy, analyzing textures, and looking for organic molecules, SHERLOC and WATSON- along with other rover instruments- help mission scientists and engineers to better understand the geologic history of Jezero crater, search for potentially habitable environments, characterize astrobiologically-interesting rocks, and select which targets to sample for future return to Earth. These robotic gumshoes are continuing to make exciting discoveries about Mars as Perseverance roves across the surface of our neighboring red planet, and with each new discovery they remind us of the original Holmes, who said “Education never ends, Watson. It is a series of lessons, with the greatest for the last.”

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
  • 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
  • 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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