'We've reached the point of teleoperations now that I think it's feasible to mine the moon,' Baiden said. Mining robots could be controlled from Earth. Such a timeline may seem ambitious, but the technology to start up a primarily robotic lunar mining operation exists today, panel members said. Shackleton Energy Company, for example, hopes to be selling rocket fuel in orbit by 2020, according to its founder Bill Stone, who was not a member of the conference panel.

Indeed, some companies are already drawing up plans to mine moon water for this very purpose. According to that argument, it makes economic sense to supply the filling stations from the moon because its gravity is one-sixth that of the Earth, and thus launching from there is much cheaper. Such an arrangement could revolutionize how humanity uses space, spurring a huge wave of trade, travel and discovery, scientists and entrepreneurs alike have argued. Propellant could be produced from moon water and sold at refueling stations in low-Earth orbit, allowing spaceships and satellites to top up their tanks in space. It can also be separated into its constituent hydrogen and oxygen, the chief components of rocket fuel. This water is so valuable not just for its potential to keep future moon dwellers hydrated.

'Mining water on the moon is going to be a lot easier than we thought.'

It's unbound,' said Paul Spudis, a scientist at the Lunar and Planetary Institute in Houston, during the panel discussion. 'We now know the water there is free water. Frigid craters at both lunar poles have likely been trapping and accumulating water for billions of years - water that is relatively pure and easy to get at. The moon has a lot of water ice, as recent discoveries have made clear. Private enterprise, Baiden and others said, will likely lead the way to mining the moon because there's so much money to be made, but it will probably need government to prime the pump.

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