Here is a neat interview with an MIT scientist (Sara Seager) that has signed onto the venture talking about some of the technical aspects of the project. There are a couple of salient points that she makes in the interview that I think are worth mentioning.
- The mining will have to be done by robots. In addition, the robot technology is essentially there right now to do it. That is because mineral and oil extraction is currently taking place at the bottom of the sea, which is a close parallel to space in regards to environment, ruggedness, etc.
- There are two ways to mine the asteroid: send robots to the rock, mine the rock, and return. OR, send robots to the rock, lasso the rock, tow it to a lunar orbit, and then different robots to the rock to mine it. From a purely gut-level reflex, I prefer the former alternative. No sense in bringing an extinction-level event closer to earth.