If NASA astronauts return to the moon in the next decade, they'll get to cruise the lunar surface in style.

The space agency's current plan is to send humans back to the moon by 2020, and this includes using a new exploration vehicle called Lunar Electric Rover (LER). About the size of a small pickup truck, LER has 12 pivoting wheels that enable the rover to move in any direction and turn on a dime; it features a tilting cockpit for close-up views of the terrain; and it runs on batteries and fuel cells.

This week NASA completed field tests of the rover in Black Point Lava Flow, AZ, as part of an annual event called the Desert Research and Technology Studies (D-RATS). The desert landscape--a rugged terrain of sand dunes that is subject to sandstorms and violent temperature swings--is ideal for simulating lunar exploration.

NASA began developing LER in 2007. It is now as "close to [fully] operational as possible,"says Michael Gernhardt, an astronaut and manager of the Environmental Physiology Laboratory at NASA's Johnson Space Center (JSC) in Houston.

The new rover is pressurized so that astronauts can safely explore much more of the moon's surface. During the Apollo program, exploration was limited by the distance astronauts could walk in their spacesuits in case their rover broke down--approximately 9.7 kilometers. LER has a range of about 241 kilometers because astronauts could safely reside inside until rescued by another rover--NASA plans to have at least two on the surface simultaneously.

The new rover weighs four tons, has a 20-horsepower engine, and can traverse 30-degree slopes and climb over meter-sized boulders. "It's a beast," says Rob Ambrose, a human robotics engineer at JSC, who works on LER.

LER's 12 wheels are driven by two electric motors and can pivot 360 degrees, allowing the vehicle to travel in a sideways, crablike motion. "If things get complicated, it has a way to wiggle its way out, and it can lift its legs up and down to stay out of trouble," Ambrose says.

LER is a plug-in electric vehicle that uses battery technologies similar to those in a consumer or commercial electric vehicle. Currently it uses a lithium-ion battery with 125 watt-hours per kilogram, but the working rover will need a battery with 200 watt-hours per kilogram. Inside the vehicle is an exercise bike that the astronauts can use to charge the batteries.