Some of the asteroids have shown that these celestial bodies may contain huge number of minerals including Nickel, iron, cobalt, palladium, platinum, manganese, gold, molybdenum, etc. moreover, according to some scientists, part of the ore mined on Earth has come to the planet from space during the "asteroid bombardment". A large asteroid can replace a huge Deposit, and obtained from it the minerals enough the population of the Earth for a few years.
To get raw materials in space, you must first find a suitable celestial body. The asteroid must be relatively close to the Earth, to the way there and back occupying too much time and did not require large expenditures. It is desirable that nearby you can find water because it will significantly reduce transportation costs of materials needed for survival. And, of course, the asteroid needs to be rich in minerals.
Finding the right "space field," you need to choose a mining method. Three main options. If the surface of a celestial body is, the fragments of rock, they can be extracted in an open way. This means that the asteroid should create something like an earthly career, which will break up the material and deliver it in a special vault. If it is determined that the minerals are in the depths of the asteroid, you need to build the mine, complemented by systems that automatically deliver materials to the surface. And finally, if you were able to discover that the asteroid is covered with small metal fragments and tiny, the metal can be collected using a special magnet.
For the extraction of raw materials on asteroids required special equipment. First, it should be automatic, allowing to minimize the human intervention in the process. Secondly, this equipment should work in open space. Finally, note that because of the very low-gravity asteroid may not be able to hold larger devices, and will need some way to securely attach to the surface.