SEATTLE — Space-faring robots could be extracting gold and platinum from asteroids within 10 years if a new venture backed by two Silicon Valley titans and filmmaker James Cameron gets off the ground as planned.

Outside experts are skeptical about the project because it would probably require untold millions or perhaps billions of dollars and huge advances in technology. But the same entrepreneurs pioneered the selling of space rides to tourists, a notion that also seemed fanciful not long ago.

“Since my early teenage years, I’ve wanted to be an asteroid miner. I always viewed it as a glamorous vision of where we could go,” Peter Diamandis, one of the founders of Planetary Resources, told a news conference Tuesday at the Museum of Flight in Seattle.

The company’s vision “is to make the resources of space available to humanity.”

The inaugural step, to be achieved in the next 18 to 24 months, would be to launch the first in a series of private telescopes that would search for the right type of asteroids.

The plan is to use commercially built robotic ships to squeeze rocket fuel and valuable minerals out of the rocks that routinely whiz by Earth. Company leaders predicted that they could have their version of a space-based gas station up and running by 2020.