`` It was hardcore . Musk : Commercial space flight wo n't be affordable without reusable rockets . CEO of SpaceX gives keynote at South by the International Space Station . The SpaceX Dragon is currently docked at Southwest Interactive festival . Elon Musk also is CEO and chief designer at Musk , maker of electric cars .
Musk : Commercial space flight wo n't be affordable without reusable rockets . CEO of SpaceX gives keynote at South by the International Space Station . The SpaceX Dragon is currently docked at Southwest Interactive festival . Elon Musk also is CEO and chief designer at Musk , maker of electric cars .