NASA has given its Perseverance Mars rover a powerful new ability to determine its exact location on the Red Planet without waiting for instructions from Earth, effectively giving the six-wheeled explorer its own version of GPS.
Unlike on Earth, Mars has no network of navigation satellites. Instead, robotic missions including Perseverance have long depended on onboard sensors and cameras, imagery from orbiting spacecraft and guidance from mission teams millions of miles away to figure out precisely where they are.
“For pinpoint accuracy, it needed humans back on Earth,” she added. “But not anymore.”
Since landing in Jezero Crater in February 2021, the car-sized Perseverance has tracked its position by analyzing geological features in images taken every few feet and factoring in wheel slippage to estimate how far it has traveled.
Small errors build up over time, and, on longer drives, those inaccuracies can leave the rover unsure of its position by more than 100 feet (35 meters). If it calculates that it may be too close to hazardous terrain, the rover may stop early and wait for clarification from Earth, according to a NASA statement.
“Humans have to tell it, ‘You’re not lost, you’re safe. Keep going,'” Verma said in the statement. “We knew if we addressed this problem, the rover could travel much farther every day.”
Because Mars is on average about 140 million miles (225 million kilometers) from Earth, communication delays make real-time control impossible, and such guidance for direction can take a full Martian day or longer.
Now, with the new upgrade, called Mars Global Localization, Perseverance can match its own panoramic imagery to orbital terrain maps onboard, calculate its precise position and continue along its planned route without waiting for Earth-based confirmation.
An onboard algorithm performs the comparison in about two minutes and can pinpoint the rover’s location to within roughly 10 inches (25 centimeters), all without assistance from human planners, NASA said. This capability allows the rover to travel significantly farther, increasing the amount of terrain it can explore and the science it can conduct, scientists say.
The team began developing the technology in 2023, testing the algorithm against imagery from 264 previous rover stops. In every case, the software correctly identified the rover’s location, according to the agency. The system was successfully used during routine operations in early February and again earlier this week.
“We’ve given the rover a new ability,” Jeremy Nash, a robotics engineer at JPL who led the project under Verma, said in the statement. “This has been an open problem in robotics research for decades, and it’s been super exciting to deploy this solution in space for the first time.”
The advancement comes just weeks after NASA announced that Perseverance had completed its first drive on Mars fully planned by generative artificial intelligence.
In that test, AI software analyzed the same images and terrain data used by human planners — including imagery from NASA’s Mars Reconnaissance Orbiter — to identify hazards such as rocks, steep slopes and boulder fields, then mapped out a safe route with designated coordinates for the rover to follow.
Before transmitting the commands to Mars, engineers tested the plan extensively using a detailed digital twin of the rover to ensure it could safely execute the drive, NASA said in a previous statement.
In fact, Perseverance’s autonomous navigation capabilities have become so effective at detecting and steering around obstacles that its driving range has been limited less by hazard avoidance and more by uncertainty about its precise location, scientists say.
Such technology could help usher in a new era of faster, more autonomous exploration not just on Mars, but on other worlds as well, Verma said in the statement.
“It could be used by almost any other rover traveling fast and far.”