At TED2013, Musk talked about his dream of building reusable rockets — a dream he’s seen realized with the success of the Falcon 9, which to date has had nine successful launches and landings. Earlier this year, a used rocket completed a second successful mission and landing for the first time in history. “It’s the first reflight of an old booster where that reflight is relevant,” Musk says. “Reusability is only relevant if it is rapid and complete, like an aircraft or a car … You don’t send your aircraft into Boeing in between flights.”