Less than a week after leading SpaceX through a record IPO, CEO Elon Musk has bolstered the rocket maker's board with another longtime friend and ally, Roelof Botha. In a filing on Wednesday, SpaceX said Botha will serve as an independent director and a member of the company's audit committee starting immediately. Botha becomes the eighth board member at SpaceX, where Musk serves as chairman, in addition to his roles as CEO and technology chief. Since 2003, Botha has worked at venture firm