The Curiosity rover exploring Mars boasts impressive technology but future rovers will need more smarts to explore more distant worlds, U.S. scientists say.

While the unmanned Curiosity mission has made major strides in landing on and finding its own way on a distant planet, new and better technology is needed if future rover missions are to make discoveries further out in the solar system, they said.

One step under way is the development of a new camera that can do more than just take pictures of alien rocks, researchers said; it also thinks about what the pictures signify so the rover can decide on its own whether to keep exploring a particular site or move on.

"We currently have a micromanaging approach to space exploration," Kiri Wagstaff, a computer scientist and geologist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., said. "While this suffices for our rovers on Mars, it works less and less well the further you get from the Earth. If you want to get ambitious and go to Europa and asteroids and comets, you need more and more autonomy to even make that feasible."

As part of that goal, Wagstaff and her colleagues have developed an advanced two-lens camera, called TextureCam, with its own computer processor which can analyze images it captures so the rover can decide on its own whether to keep exploring a particular site, or move on.

"Right now for the rovers, each day is planned out on Earth based on the images the rover took the previous day," Wagstaff said. "This is a huge limitation and one of the main bottlenecks for exploration with these spacecraft."

"If the rover itself could prioritize what's scientifically important, it would suddenly have the capability to take more images than it knows it can send back. That goes hand in hand with its ability to discover new things that weren't anticipated," she said.

"You do have to provide it with some initial training, just like you would with a human, where you give it example images of what to look for," Wagstaff said. "But once it knows what to look for, it can make the same decisions we currently do on Earth."

In initial testing, TextureCam was trained using technology similar to the facial unlock feature available on smartphones and computers, and the more examples of interesting rocks it was shown, the better it became at identifying the common features that made the rocks scientifically important, the researchers said.

Wagstaff and her colleagues have reported their developments in the journal Geophysical Research Letters.