NASA's New ERNEST Rover Prototype Drives 10 Times Faster Than Current Mars Explorers

For decades, NASA’s robotic explorers have crawled across alien landscapes at a glacial pace, prioritizing stability over speed. But a new prototype is poised to change the tempo of planetary exploration. During a recent field test in the Colorado Desert, a four-wheeled rover named ERNEST successfully navigated 16 miles of rugged terrain in just 37 hours of driving. The prototype, whose name stands for Exploration Rover for Navigating Extreme Sloped Terrain, represents a fundamental shift in how space agencies approach off-world mobility.[1][2][3][5]

The most striking upgrade is the rover's speed. ERNEST reached a top speed of 0.6 miles per hour during the seven-day intermittent testing campaign. While that pace might be unremarkable for a human on foot, it is roughly ten times faster than the top speeds of Curiosity and Perseverance, the two operational rovers currently exploring Mars. For planetary scientists, this velocity unlocks the possibility of conducting a "science road trip" across the Moon or Mars, vastly expanding the number of geological sites a single mission can visit.[2][3][4][5]

This leap in performance stems from a complete redesign of the rover's undercarriage. Since the Sojourner rover landed on Mars in 1997, NASA has relied on a passive "rocker-bogie" suspension system, which uses pivot points to keep all six wheels on the ground but struggles with steep slopes and large obstacles. ERNEST abandons this 30-year-old paradigm in favor of a two-degree-of-freedom active gimbal suspension. Using a clutch mechanism, the rover can toggle between a passive mode to conserve energy on flat ground and an active mode to tackle extreme terrain.[1][3][5]

In its active mode, ERNEST operates more like a mechanical gymnast than a traditional vehicle. Two powered joints on each wheel allow the rover to independently lift its wheels to step onto or over large rocks. The four steerable wheels enable the machine to drive in any direction, including sideways, and execute alternative gaits that engineers describe as "squirming" and "wheel-walking." This agility allows the rover to extricate itself from loose sand or climb steep ridges that would permanently strand older models.[1][2][3][6]

The choice of wheels also reflects hard-learned lessons from the Red Planet. Both Curiosity and Perseverance utilize rigid aluminum wheels, which have suffered significant wear, tear, and puncturing from the sharp, jagged rocks scattered across the Martian surface. ERNEST, by contrast, runs on compliant wire-mesh wheels. These flexible wheels conform to the terrain, providing better traction on loose soil and absorbing the impact of sharp rocks, which is critical when traveling at ten times the speed of previous rovers.[3][5]

Hardware is only half the equation; ERNEST also features a major upgrade in artificial intelligence. Because communication delays between Earth and Mars can last up to 24 minutes each way, rovers must be able to navigate safely without waiting for human commands. To achieve this, the Jet Propulsion Laboratory (JPL) trained ERNEST’s navigation system using reinforcement learning, moving away from strictly pre-programmed manual code.[3][6]

The reinforcement learning framework was developed using JPL's Dynamics and Real-Time Simulation (DARTS) engine, which combines rigid-contact dynamics with advanced terramechanics. By running thousands of virtual driving hours across procedurally generated terrain, the neural network learned optimal movement strategies through trial and error. When deployed in the actual desert, the AI seamlessly translated its virtual training into real-world locomotion, adapting its gait on the fly as the terrain shifted beneath it.[3][5][6]

The physical testing in the Colorado Desert was designed to push these autonomous systems to their limits. The JPL team deployed the four-foot-long prototype at all hours of the day, including pre-sunrise and nighttime runs. These dark conditions were specifically chosen to simulate the long, harsh shadows and dim lighting expected at the lunar south pole, a primary target for upcoming Artemis missions. Despite the lack of visibility, ERNEST’s onboard AI handled the extreme lighting and navigated the obstacles without requiring human intervention.[3][5][6]

The success of the ERNEST prototype opens up entirely new destinations for future space missions. Current rovers are often forced to take long, circuitous detours to avoid hazardous slopes or rocky fields. With its active suspension and mesh wheels, ERNEST could directly access steep crater walls, ancient lava tubes, and permanently shadowed craters where water ice is believed to exist.[1][3]

While ERNEST is currently a small, four-foot prototype, the technology is highly scalable. NASA engineers are already using the data gathered from the desert campaign to design a flight-ready version that would be twice the size, capable of supporting long-duration, heavy-payload missions. By combining unprecedented speed, active mobility, and advanced autonomy, ERNEST is laying the groundwork for a new era of robotic explorers that will traverse the solar system faster and tougher than ever before.[1][2][4][5]