Elon Musk is not one to let setbacks slow him down, even when setbacks involve the explosion of a rocket containing cargo precious to fellow tech billionaire Mark Zuckerberg. As of this week, SpaceX, where Musk is CEO, is back in the business of launching rockets. And Musk is pushing ahead on his outsize ambitions for the company. After 17 successful launches between 2012 and 2015, SpaceX initially planned to launch 20 rockets in 2016.