Electrocar and rocket tycoon Elon Musk says he'll put the first human beings on Mars well before the 2020s are finished – and also promised to float his SpaceX firm on Earth stock exchanges once the interplanetary mission gets underway.

"I'm hopeful that the first people could be taken to Mars in 10 to 12 years, I think it's certainly possible for that to occur," he told CNBC. "But the thing that matters long term is to have a self-sustaining city on Mars, to make life multi-planetary."

Musk said that the SpaceX goal was essential to the future survival of humanity. Either mankind would slip the surly bonds of Earth and become an interplanetary species, or remain a single-planet culture and become extinct due to a man-made or natural catastrophe.

Musk's schedule puts him well ahead of NASA, which is only talking about getting man to Mars by the 2030s – and then only if it can get billions in public funding and build a rocket big enough for the job. Musk's Falcon Heavy booster is scheduled to fly within the next year, and will carry enough payload to make assembling a Mars spaceship possible.

That's not to say Musk sees himself competing with the space agency. He paid tribute to NASA, saying that without that agency's pioneering work, SpaceX couldn't have got as far as it has.

Musk said that SpaceX is happy to carry on working with NASA, delivering cargo up to the International Space Station, and hopes to win a contract to deliver crew in the company's updated Dragon capsule. But if it doesn't win more contracts, Musk said he was confident the firm could still make it to the Red Planet.

Part of the funding could come from a float of the privately-held company on the stock exchange. This would be difficult, he said, given that the financial markets are obsessed with quarterly and annual goals – but it should be possible once the technology has been perfected.

"We need to get where things are steady and predictable," Musk said. "Maybe we're close to developing the Mars vehicle, or ideally we've flown it a few times, then I think going public would make more sense."

Meanwhile, back on Earth, Musk said that he hoped his Tesla venture would have a mass-market car ready for public consumption within the next three years. The big challenge is getting a battery that can be built for less than $5,000, but he said that the company was in daily meetings with Panasonic trying to sort out the problems involved. ®