A critical aspect of this is being able to mine asteroidal material and process it, which Nasa and its contractors are studying. One line of thinking is that mined metals can be used to build structures in space that would be very difficult and pricey to construct on Earth and launch. Examples abound, including big spacecraft to use for crewed exploration of the planets, giant telescopes in orbit, space stations, and more. While the cost of the International Space Station (ISS) is estimated to be $100bn, much of that was simply getting previously-built components into space in the first place. If you already have those pieces in space, the cost is far less.
Smelting material in the near-weightless environment of an asteroid is one thing, but creating complex components of spacecraft is another. Manufacturing is likely to be easier in gravity, and the Moon is a perfect compromise for this.
Getting the materials to the Moon is not hard from an asteroid mining operation. And once built, getting even massive components off the Moon’s surface is far, far easier than it would be from Earth due to lower gravity and lack of air (it took a tremendous Saturn V rocket full of fuel to get to the Moon, but only the tiny Apollo ascent module to get back off). Building vehicles and other space-based structures on the Moon is vastly easier and less expensive than it would be here on Earth. From there, the rest of the solar system is an easy trip.
And that's just one reason we might go back to the moon. There's lots more to read at the BBC's Future blog. Link -via mental_floss
(Image credit: Small Artworks)