Nearly 25 years ago, a mariachi band played at a SpaceX party while Elon Musk posed for a photo. The rocket company's head count was single digits back then. Today, it's over 22,000. SpaceX started with two long-shot goals: make rockets cheaper to launch and, eventually, send mankind to Mars. More than two decades later, Elon Musk's space company has decisively accomplished the first, and went public on Friday at a historic $1.8 trillion valuation. The trading milestone followed years of fiery