On Friday, asteroid 2012 DA14 will pass within 17,200 (27,700km) of Earth. DA14 is about 50 meters wide, and will be the closest ever fly-by of a celestial body that astronomers have known about in advance. If that wasn't thrilling enough, though, celestial mining company Deep Space Industries is saying that the asteroid, if we were to harvest its resources, may contain nearly $200 billion of minerals and water.