WASHINGTON -- In the not too distant future, flesh-and-bone astronaut explorers may meet their match as automatons become increasingly imbued with the robotic "right stuff."

In years to come, NASA robot experts see an increasing need for humans and robots fulfilling assignments in space together. While not prioritized as yet, "a cloud of possible missions are out there," said David Lavery, NASA program executive for solar system exploration.

Working on robotics for some 15 years, Lavery said a main research thrust of NASA is giving an operator the ability to not only see what a robot sees, but to also allow that person to be fully "immersed" in the environment surrounding the robot.

A Mars rover, for instance, could speedily work its way to pre-picked rocks or perform other science errands, Lavery said. Time-consuming slow crawls like that done in 1997 by the Sojourner mini-rover would be left in the Martian dust -- a 20th-century relic of how work was done on the Red Planet.

"You could feel the texture of a rock, or the pressure from a robot's grasp of a solar array, or removing a panel. The robot, in effect, is the operator's remote hands," he said.

The space agency is already at work on an advanced humanoid system called Robonaut, Lavery said. Robonaut is now under development at the NASA Johnson Space Center in Houston, Texas. In appearance, this robot is very similar to a human upper torso.

Robonaut will mimic the motion of human astronauts sitting elsewhere, such as within the pressurized volume of the International Space Station. "It will be equivalent to a human in a spacewalking suit, with a high level of dexterity," Lavery said.

The anthropomorphic robot is the size of an astronaut in a spacesuit and configured with two arms, two five-fingered hands, a head and a torso. Robonaut is not now intended for flight. It could be assigned to the space station, ready for service perhaps by the end of the decade, he said.

While space robotic work is very promising, "we constantly have to calibrate expectations," admitted Lavery. Public images of those classic Star Wars robots, R2D2 and C3PO, shore up expectations such wonders are just around the corner, he said.