Tesla and SpaceX founder Elon Musk told an audience at South by Southwest that his timeline for sending a space vehicle to Mars could mark its first milestone early next year.

The privately-funded venture, announced in September 2017, aims to send a cargo mission to the Red Planet by 2022. SpaceX’s ultimate objective is to plant the seeds to put a human colony on Mars.

Musk held a surprise question and answer session at the annual technology and culture festival in Austin, Texas on Sunday. The billionaire told attendees that “we are building the first Mars, or interplanetary ship, and I think well be able to short trips, flights by first half of next year.”

Mindful of elevating expectations too high, Musk hedged a bit. “Although sometimes, my timelines are a little, you know…” he said to laughter.

SpaceX’s BFR rocket system is expected to have capabilities for interplanetary travel, and be fully reusable. A flight will cost less than the initial Falcon 1 flights, which Musk pegged in the $5 to $6 million range.

He hopes if BFR launches, others will believe Mars travel is possible, and follow suit.

“The biggest thing that would be helpful is just general support and encouragement and goodwill,” Musk said. “I think once we build it we’ll have a point of proof something that other companies and countries can go and do. They certainly don’t think it’s possible, but if we do they’ll up their game.”

In the immediate term, Mars will need Glass domes, a power station, and an assortment of basic living fundamentals, he cautioned. After the infrastructure is complete, “then really the explosion of entrepreneurial opportunity [will begin], because Mars will need everything from iron foundries to pizza joints,” he said.

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