Speaking at the International Astronautical Congress (IAC) in Adelaide, South Australia, Musk unveiled plans to launch SpaceX’s (SPACEX) BFR rocket and begin its Mars rendezvous by the year 2022, first sending two cargo missions to scout water sources and build a fuel plant. Then the city-building begins.

Musk said he’s “confident” the plan will be under way within five years.

“I can’t think of anything more exciting than going out there and being among the stars,” Musk said, adding that he thinks SpaceX has figured out a way to make it affordable by using revenues from the company’s satellite launches, service missions to the International Space Station and by making smaller, more efficient rockets that are mostly reusable.

Nine years after SpaceX’s first successful launch — its fourth ever — Musk said his engineers are now perfecting propulsive landing. He believes the BFR rocket can carry out missions to the moon and back without producing propellant, enabling the establishment of a lunar space station.

“It’s 2017, we should have a lunar base by now,” Musk said to applause. “What the hell is going on?”

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Travel to and from Mars will, however, require a propellant production plant. Current rocket prototypes provide cabin space suitable for about 100 people per mission, he said. Following the two projected missions in 2022, Musk said SpaceX plans to send four more rockets to the red planet during the next available window in 2024. Once colonization is under way, then begins the task of “making it a nice place to be.”

Founded by Musk in 2002, SpaceX designs, manufactures and launches spacecraft and advanced rockets toward the ultimate goal of enabling human life on other planets.

But Musk, who also co-founded and serves as CEO of Tesla Motors (TSLA), remains grounded in his ambitions. SpaceX could potentially change the way we travel around the globe, he said, making it possible to get anywhere on earth in less than hour. “If we’re building this thing to go to mars,” Musk asked, “why not go to other places on earth as well?”