Hunkering Down for Solar Conjunction
Geometry of Mars Solar Conjunction: During solar conjunction, Mars and the Earth are at their furthest distance. From Earth, Mars appears to be very close to the Sun in the sky, and charged particles from the Sun can interfere with transmissions sent to Perseverance. Credits: NASA/JPL-Caltech. Download image ›

There’s no way around it: due to their orbits, Mars and the Earth have to stop communicating with each other for about two weeks every two years. This quiet period is called solar conjunction, and for the Perseverance team that means we can’t send new instructions to the rover between sols 217-235 (Sept. 28 – Oct. 17). 

We’ve already sent Perseverance a set of commands so it can perform science activities without having “ground in the loop,” meaning that they pose no risk to the rover’s safety, and the team won’t need to check that they successfully completed each day. 

In my role on the science team as a Long-Term Planner, I work on the strategic plan for what the rover will do in the next days, weeks and months. Lately, that includes experiments that can be repeated before and after the conjunction break, which are unique opportunities to monitor longer-term changes to the rocks and soils around the rover. To look for differences in the terrain due to the wind moving sand and dust, we will take a 360-degree panorama with Navcam on sol 214, and again on sol 236.

We’ll also repeat detailed measurements of the soil composition using SuperCam and Mastcam-Z. Because it generates a lot of heat, we’ll look underneath the rover’s radioisotope thermoelectric generator (RTG) to see if the soil dehydrates over time. If this happens, the rover’s spectrometers might pick up subtle changes to key absorption features.

Solar conjunction gives the science team a much-needed break from operations, but it’s not exactly vacation time. We have a lot of data from our recent weeks of exploring South Séítah to scrutinize, and big decisions coming up. As a Long-Term Planner, I will be helping to lead telecons each week during conjunction so the science team can discuss where we should collect our next samples in South Séítah– and beyond. 

Solar conjunction is also an opportunity for us step back and reflect. In our day-to-day operations, it’s easy to stay deep into the weeds of mission technicalities, and to lose sight of the profundity of operating a robot on an alien world. The rover datasets are so detailed that we spend hours scrutinizing a patch of rock the size of a postage stamp and can forget that these rocks are more than a hundred million miles away! But solar conjunction is a reminder that this work isn’t your standard day job, and that Mars isn’t just a geologic field site – it’s an astronomical object, performing its own cosmic dance around our common Sun. 

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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