SpaceX billionaire Elon Musk may have his heart set on building a city on Mars, but Amazon billionaire Jeff Bezos’ space vision looks closer to home. He’s gazing at the moon.

“I think we should build a permanent human settlement on one of the poles of the moon,” Bezos said today during a Q&A with kids at Seattle’s Museum of Flight. “It’s time to go back to the moon, but this time to stay.”

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Bezos has talked about moon missions before, and he’s even told NASA that his Blue Origin space venture could make Amazon-like deliveries to the moon, as part of a program called Blue Moon.

Today he went into more detail about his space aspirations when students asked him questions at the Museum of Flight’s “Apollo” exhibit. Bezos’ backdrop for the event included the decades-old pieces of Saturn V rocket engines that he arranged to have recovered from the Atlantic Ocean, plus an intact, never-flown engine of the same type.

Bezos said his dreams of spaceflight were fostered at the age of 5 when he watched NASA astronaut Neil Armstrong take humanity’s first steps on the moon in 1969. Now he’s able to follow through on those dreams – in large part because of the success of Amazon, the online retail company he founded in 1994.

A couple of months ago, Bezos acknowledged that he’s funding Blue Origin to the tune of a billion dollars a year, fueled by his sales of Amazon stock.

Blue Origin is ramping up its employment count and making progress on two big projects: the New Shepard suborbital spaceship, which has made five successful test flights to space and back; and the New Glenn orbital rocket, which will make use of Blue Origin’s BE-4 rocket engine.

New Shepard could start flying passengers as early as next year, which would provide opportunities for suborbital space experiments as well as space tourism.

“There’s a long history of tourism and entertainment driving innovations in technology,” Bezos pointed out. For example, barnstorming and joyrides helped sustain pilots and airplane-makers in the early days of aviation. Today, advances in machine learning, computer vision and artificial intelligence are being driven by improvements in graphics processing units, or GPUs.

“Why were GPUs invented? For one purpose, and one purpose only: They were invented by Nvidia for playing video games,” Bezos said.

On the orbital front, Blue Origin is currently testing the BE-4 engine and building a multimillion-dollar production facility and launch center in Florida to accommodate New Glenn rockets.

“That vehicle will fly in in 2020 for the first time,” Bezos said. Blue Origin already has lined up its first customers for New Glenn satellite launches in the early 2020s.

Bezos is clearly thinking about frontiers beyond Earth orbit: When asked about the potential impact of artificial intelligence on space operations, he said AI will point the way for “even better robotic probes to explore the solar system.”

Today, Mars rovers have to wait for detailed instructions from mission controllers on Earth on how to avoid that potential hazards they come across. “That’s one of the reasons that you get to cover very little ground with those rovers,” Bezos said.

“But if you had really good self-driving technology, machine vision and other things, those rovers could keep themselves safe and they could go faster and explore much more in a given amount of time,” he said.

They could also help build that city on the moon.

“There, you would want to pre-position a whole bunch of equipment and supplies before the humans show up, and some of those things might need to be assembled on the surface of the moon,” Bezos said. “And that’s the kind of thing that could also be done by advanced robotics with machine-learning systems on board.”

Bezos noted that the moon’s polar regions would be the best places to build a base, because some craters in those regions are thought to contain reserves of water ice that are shielded from sunlight. That ice could be converted into liquid water for drinking, hydrogen for fuel, and oxygen for breathable air.

During past talks, Blue Origin executives have made clear that it expects lunar settlements to be created as the result of private-public collaboration, rather than purely private-sector or purely NASA-funded undertakings.

Why go to the moon? Almost 55 years ago, President John Kennedy said America chose to embark on missions to the moon “not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills.”

Bezos’ moon ambitions are motivated by more down-to-earth considerations: He argues that in order to keep up with a global population’s growing demands for energy and manufactured goods, we earthlings will eventually have to take advantage of resources and territories beyond Earth.

“I want to see millions of people living and working in space,” said Bezos, repeating what has become a mantra for Blue Origin.

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