Overview:Discover how the big, bold ideas of Silicon Valley are helping launch a new era of private space exploration in this half-hour KQED Science documentary. From space tourism to mining the moon to companies ferrying NASA astronauts into space, a new wave of commercialization is shaking up the $300-billion global space industry. Meet a new generation of entrepreneurs, sprung from the high-tech culture of Silicon Valley, who are venturing into the new "wild west" of space exploration in search of their space gold. But are there new risks when space is no longer the exclusive domain of big governments?