NEW YORK, United States (AFP) — Shares in Elon Musk's SpaceX jumped more than 20 per cent on their trading debut Friday after the biggest IPO in history, making the polarising entrepreneur the world's first trillionaire as he vowed to take humanity to Mars. The blockbuster initial public offering, which raised more than $75 billion, is expected to kick off a series of major IPOs by AI companies in the...