23.12.2025
NASA loses contact with MAVEN, Perseverance continues roving around Jezero
In early December, NASA lost contact with its MAVEN spacecraft, which has been orbiting Mars since 2014. MAVEN was supposed to reestablish communications with NASA’s Deep Space Network on Dec. 6 after emerging from behind Mars during a routine blackout period when the spacecraft’s orbit takes it behind the red planet, blocking all communications to and from Earth. Teams have worked to regain contact, but all attempts have been unsuccessful.
Meanwhile, on the Martian surface, NASA’s Perseverance rover continues to drive toward its next target in Jezero Crater, searching for signs of ancient microbial life in various rocks and minerals along the way. The rover’s team is using the time to analyze the condition of Perseverance and its components, informing new estimates of how long the rover’s mission might last.
NASA attempts to reestablish communications with MAVEN
On Saturday, Dec. 6, NASA scientists lost contact with the agency’s Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft, which is located in orbit around Mars. MAVEN launched to Mars in November 2013 and entered orbit in September 2014, where it has been studying the Martian atmosphere and its disappearance due to solar wind. MAVEN’s research into Mars’ atmospheric loss has also provided insight into the evolution of the red planet’s climate.
MAVEN launches to Mars atop an Atlas V. (Credit: NASA/Bill Ingalls)
MAVEN’s team communicates with the spacecraft through NASA’s Deep Space Network (DSN)– a worldwide network of large radio antennas that send and receive signals from NASA’s fleet of spacecraft throughout the solar system. Normally, when MAVEN’s orbit takes it behind Mars, teams briefly lose contact with the spacecraft until it emerges and reestablishes contact with the DSN. However, on Dec. 6, the DSN received no signals from MAVEN after it orbited behind Mars. Interestingly, before moving behind Mars, data sent to Earth from MAVEN on Dec. 4 showed that all its subsystems and electronics were working as expected.
In a Dec. 15 statement, NASA explained that while all attempts to regain contact with MAVEN have been unsuccessful, mission teams were able to retrieve a small amount of tracking data from Dec. 6. The tracking data revealed that MAVEN was in an unexpected spin when it emerged from behind Mars, and the frequency of the signal suggests that the spacecraft’s orbit may have been altered. NASA and MAVEN teams will continue to attempt to reestablish contact with the spacecraft over the next few weeks while analyzing tracking data for more clues about what happened when MAVEN was behind Mars.
MAVEN’s loss of contact has additional impacts on the operation of other missions at Mars, most notably surface spacecraft like Perseverance and Curiosity. MAVEN works with NASA’s Mars Reconnaissance Orbiter (MRO), Mars Odyssey, and the European Space Agency’s (ESA) ExoMars Trace Gas Orbiter to relay communications to and from the rovers. With MAVEN out of service as a communications relay, NASA is working with MRO, Mars Odyssey, and ESA teams to ensure communications between Earth and the rovers can continue for the next two weeks. Perseverance and Curiosity teams are also adjusting their mission planning to account for the new communications setup without MAVEN.
Perseverance continues its trek around Jezero
Feb. 18, 2026, will mark the fifth anniversary of Perseverance’s landing on Mars. In the five years since its landing, the rover has traveled an approximately 40 km path through Jezero Crater, collecting surface samples along the way and searching for signs of ancient microbial life. As 2026 draws near, the rover is now driving to a new region of Jezero named “Lac de Charmes.” There, it will search for new surface sample collection locations and targets.
As Perseverance makes its way to Lac de Charmes, the rover’s team at NASA’s Jet Propulsion Laboratory (JPL) is evaluating the condition of its subsystems and components and how they’ve withstood 40 km of near-daily driving. JPL teams are testing duplicate parts on Earth to better understand their durability; one such test this summer confirmed that the rotary actuators in Perseverance’s wheels are expected to perform as expected for at least another 60 km of driving. JPL teams are currently performing similar tests on the rover’s braking system.
After continuous testing over two years, Perseverance teams believe the rover will continue to operate in its current condition until at least 2031. However, Perseverance is built much like its sister rover, Curiosity, which landed on Mars in 2012, has driven 36 km up and around Mount Sharp — a 5.5 km-tall mountain at the center of Gale Crater. Curiosity’s continued operation is a good sign for the longevity of Perseverance‘s mission.
Panorama image of Lac de Charmes taken by Perseverance. (Credit: NASA/JPL-Caltech/ASU/MSSS)
“These tests show the rover is in excellent shape. All the systems are fully capable of supporting a very long-term mission to extensively explore this fascinating region of Mars,” said Perseverance‘s deputy project manager Steve Lee of JPL.
While Curiosity has been on Mars for nine years longer than Perseverance, Perseverance has already driven farther than Curiosity. This is largely due to Perseverance‘s slightly faster driving speed and autonomous driving capabilities. While driving across the Martian surface, Perseverance uses an autonomous planning tool called Enhanced Autonomous Navigation (ENav), which scans a 15 m region ahead of the rover for potential hazards and obstacles. If an obstacle is identified, ENav immediately reroutes the rover around it, providing Perseverance’s six wheels with instructions on how to navigate around the hazard.
“More than 90% of Perseverance’s journey has relied on autonomous driving, making it possible to quickly collect a diverse range of samples,” said Hiro Ono, an autonomy researcher at JPL.
Perseverance‘s team at JPL plans each day of the rover’s mission and the activities it expects the rover to perform. However, after these daily plans are sent to the rover, it completes the drive entirely on its own. ENav enables Perseverance to complete this drive safely and respond to unexpected surface hazards such as sand pits, rocks, and ledges. As part of its algorithm, ENav evaluates each of the rover’s six wheels against terrain elevation, determines the trade-offs of different routes around obstacles, and ensures that the rover stays out of “keep out” areas drawn by JPL teams before a drive.
“As humans go to the Moon and even Mars in the future, long-range autonomous driving will become more critical to exploring these worlds,” Ono said.
ENav is particularly useful during drives through hazardous regions, like the “Margin Unit” — a geologic area located at the inner edge, or margin, of Jezero Crater. Perseverance climbed around 400 m of the Margin Unit from September 2023 to November 2024, collecting three surface samples and studying countless rocks for signs of ancient life. JPL scientists believe that the Margin Unit samples may show how rocks from deep within Mars interacted with surface water and the planet’s atmosphere — possibly creating conditions that could’ve supported life.
Perseverance has been particularly studying rocks with olivine — a mineral formed at high temperatures deep within a planet, offering those who study it a brief look into the planet’s interior when it formed. After analyzing the olivine identified at the Margin Unit, Perseverance scientists believe it formed when magma intruded into underground layers and cooled into igneous rock, a process known in geology as “intrusion.” Erosion at the Martian surface then exposed the igneous rock to flowing water within Jezero and carbon dioxide in the atmosphere. These interactions formed carbonates and olivine.
“This combination of olivine and carbonate was a major factor in the choice to land at Jezero Crater. These minerals are powerful recorders of planetary evolution and the potential for life,” said Perseverance scientist Ken Williford, who led the study that analyzed the rover’s findings at the Margin Unit.
Annotated image showing olivine on the “Cheyava Falls” rock discovered by Perseverance in 2024. (Credit: NASA/JPL-Caltech/MSSS)
Olivine and carbonates are great at preserving signs of ancient life and atmospheric evolution. At the base of the Margin Unit, where any rocks would have been submerged under Jezero Crater’s ancient lake, Perseverance found olivine that appeared to have been altered by flowing water. However, as the rover climbed up the Margin Unit, it found olivine with magma chambers and crystallization rather than signs of water alteration.
Once Perseverance arrives at Lac de Charmes, it is expected to find more olivine and carbonates, which scientists will analyze for signs of ancient life. Furthermore, the minerals found there will be compared more closely to those studied at the Margin Unit.
Quelle: NSF