You could do a science road trip across the Moon with this vehicle
In the Colorado Desert, a small but consequential machine called ERNEST quietly rewrote the boundaries of what robotic exploration can mean. Built at NASA's Jet Propulsion Laboratory, this prototype rover covered 16 miles in 37 hours with minimal human guidance — ten times faster than any rover currently on Mars — demonstrating that the dream of true long-range planetary exploration is no longer purely theoretical. The achievement is less about speed than about possibility: a future in which rovers conduct science road trips across the Moon and Mars, reaching terrain that has remained beyond our grasp for decades, may now be within engineering's reach.
- The 30-year-old rocker-bogie suspension system that has carried every NASA Mars rover is being challenged by a smarter, more adaptable design that can squirm, walk, and pivot in any direction.
- ERNEST's 16-mile desert run exposed a quiet urgency — current rovers like Curiosity and Perseverance cover only a few hundred meters on a good day, leaving vast regions of scientific value permanently out of reach.
- The rover's autonomous navigation software is the hidden revolution: with communication delays making real-time control impossible on the Moon or Mars, a rover that can think for itself is not a luxury but a necessity.
- Years of methodical testing — 11 suspension configurations, lunar regolith simulants, slope experiments — underscore that this is not a dramatic leap but a disciplined accumulation of engineering confidence.
- NASA's next move is to scale ERNEST to twice its size, aiming to transform a proof of concept into a vehicle capable of genuine lunar science expeditions within the coming decade.
Out in the Colorado Desert, a four-wheeled rover the size of a large toolbox recently completed a journey that would have been impossible just a few years ago. ERNEST — Exploration Rover for Navigating Extreme Sloped Terrain — covered 16 miles over 37 hours of driving with almost no human guidance, moving at speeds ten times faster than Curiosity or Perseverance. Built at NASA's Jet Propulsion Laboratory, the prototype is only 4 feet long, but what it accomplished carries implications far beyond a single stretch of sand and rock.
The achievement matters because it represents a fundamental shift in how NASA thinks about exploring distant worlds. Current Mars rovers move at a crawl, covering a few hundred meters on a good day. ERNEST's performance prompted JPL planetary scientist James Keane to envision something previously out of reach: "a science road trip across the Moon — or Mars." Future explorers could visit multiple sites and conduct research across vast territories that existing rovers could never reach.
What makes ERNEST different begins with its suspension. For 30 years, every NASA Mars rover has relied on the passive rocker-bogie system. ERNEST replaces it with an active suspension using powered joints that allow multiple gaits — squirming across loose terrain, walking on its wheels, or climbing obstacles that would stop its predecessors. Four independently steerable wheels add omnidirectional movement. The system can also switch to passive mode for energy efficiency on smoother ground.
Developing this required years of quiet, methodical work. The JPL team built two earlier prototypes and tested 11 suspension configurations in simulated lunar regolith before arriving at the current design. But mechanical innovation was only half the challenge — ERNEST also needed to think for itself. Its autonomy software allowed it to navigate those 16 desert miles with engineers trailing behind, intervening only when necessary, a capability that becomes essential when communication delays make real-time control impossible.
NASA plans to scale ERNEST to twice its current size for actual lunar missions, targeting the permanently shadowed craters and distant highlands that lie beyond the range of existing technology. What happened in the Colorado Desert was not a flashy breakthrough — it was the kind of methodical engineering work that shapes what becomes possible. ERNEST remains a prototype, but it is a prototype that works.
Out in the Colorado Desert, where the landscape stretches flat and hostile under the sun, a four-wheeled rover the size of a large toolbox recently completed a journey that would have been impossible just a few years ago. Over the course of a week, ERNEST—short for Exploration Rover for Navigating Extreme Sloped Terrain—covered 16 miles with almost no human guidance, moving at speeds ten times faster than the rovers currently exploring Mars. The prototype, built at NASA's Jet Propulsion Laboratory in Southern California, is only 4 feet long, but what it accomplished in that desert test run has implications that reach far beyond a single stretch of sand and rock.
The rover's achievement matters because it represents a fundamental shift in how NASA thinks about exploring distant worlds. Curiosity and Perseverance, the six-wheeled rovers currently roaming Mars, move at a crawl—limited by their design and the caution required when operating a machine millions of miles away with a communication delay. They can cover a few hundred meters on a good day. ERNEST, by contrast, traveled 16 miles over 37 hours of actual driving time spread across seven days of testing, reaching speeds of 0.6 miles per hour. That may not sound fast, but for a rover on another world, it opens entirely new possibilities. "You could do a science road trip across the Moon—or Mars—with this vehicle," said James Keane, a JPL planetary scientist working on lunar missions. The implication is clear: future explorers could cover ground that current rovers could never reach, visiting multiple sites and conducting research across vast territories.
What makes ERNEST different starts with its suspension system. For 30 years, every Mars rover NASA has sent has used the rocker-bogie design—a passive system that distributes weight evenly across six wheels through a series of pivot points and struts. It works, and it has proven reliable across decades of missions. But ERNEST's engineers decided to try something new. The prototype uses an active suspension system with powered joints that let the rover adjust how weight is distributed among its four wheels. This gives it multiple ways of moving: it can squirm across loose terrain, walk on its wheels like an insect, or climb over obstacles that would stop Curiosity or Perseverance dead. Add four independently steerable wheels, and ERNEST can move in any direction, including sideways. The rover can also switch between active and passive suspension modes—the active mode for rough terrain, the passive mode for energy efficiency on smoother ground.
Developing this capability required years of methodical testing. The JPL team, led by Hari Nayar, built two earlier prototypes, each about 2 feet long, and tested 11 different active suspension configurations in a trailer filled with lunar regolith simulant—material designed to mimic the texture and behavior of moon dust. They ran experiments at different slope angles over several months, refining the design until they arrived at the current version. But mechanical innovation was only half the challenge. ERNEST also needed to think for itself. The rover's autonomy software allows it to make decisions about navigation with minimal input from the engineers controlling it. During the desert test, ERNEST traveled those 16 miles with the team trailing behind, intervening only when necessary. This autonomous capability is crucial for future missions, where communication delays make real-time control impossible.
Issa Nesnas, the principal technologist at JPL who led the recent testing, framed the work as preparation for a specific goal: a long-range lunar rover mission. "This testing is helping us refine the mobility hardware and autonomy software to navigate extreme distances across a wide range of terrain and lighting conditions anticipated on the Moon," Nesnas said. The team believes they can scale ERNEST up to twice its current size and create a rover capable of the kind of extended exploration that has long been a dream of lunar scientists. The Moon's surface holds vast regions that current rovers cannot reach—permanently shadowed craters, distant highlands, areas of scientific interest that lie beyond the range of existing technology. A faster, more autonomous rover could change that.
What happened in the Colorado Desert was not a flashy breakthrough or a dramatic first. It was methodical engineering work, the kind that happens away from headlines but shapes what becomes possible in the future. ERNEST proved that the theoretical improvements to rover design could work in practice, that a rover could move faster and farther while making its own decisions about how to navigate. The next step is clear: NASA plans to build a larger version and test it in conditions even closer to those on the Moon. If that works, the science road trips James Keane mentioned could become reality—not tomorrow, but within the next decade or so. For now, ERNEST remains a prototype, a proof of concept. But it is a proof of concept that works.
Notable Quotes
This testing is helping us refine the mobility hardware and autonomy software to navigate extreme distances across a wide range of terrain and lighting conditions anticipated on the Moon.— Issa Nesnas, principal technologist at JPL
You could do a science road trip across the Moon—or Mars—with this vehicle.— James Keane, JPL planetary scientist
The Hearth Conversation Another angle on the story
Why does speed matter so much for a rover on the Moon? It's not like it's racing anywhere.
Because time is money in space exploration. Current rovers cover a few hundred meters in months. If you want to study multiple sites, compare geology across different regions, or reach areas that are scientifically interesting but distant, you need to move. Speed also means you can accomplish more science in the same mission window.
But doesn't faster mean more risk? More things can go wrong?
That's the tension ERNEST is designed to solve. The autonomy software lets the rover make decisions about terrain and obstacles without waiting for commands from Earth. It can move faster safely because it's not blind—it's evaluating the ground in real time.
The active suspension sounds complicated. Why not just improve the rocker-bogie system that's worked for 30 years?
Because sometimes good enough isn't good enough anymore. The rocker-bogie is passive—it reacts to terrain. Active suspension lets the rover choose how to move. It can adapt its gait to the surface. That flexibility opens up areas that were previously unreachable.
What happens if the autonomy software fails? Can someone take over?
Yes, but that's the whole point of the testing. They're building confidence that the software won't fail, or that it fails gracefully. ERNEST proved it can handle 37 hours of driving with minimal human intervention. That's the foundation for trusting it on the Moon.
How close are we to actually sending this to the Moon?
The prototype works. Now they need to scale it up and test it in lunar-like conditions. That's probably years away, but the hard part—proving the concept works—is done. ERNEST showed it's possible.