Elon Musk's SpaceX has made its stock market debut, with shares pushing well past their opening price of $135 (roughly €117) in the hours after the initial public offering (IPO) on the Nasdaq on Friday.

The shares were hovering around the $173 mark shortly after 1 p.m. in New York (1700 GMT/UTC), a rise of almost 28%, equating to a market capitalization of around $2.26 trillion for the Texas-based space and satellite and broadband internet company.

That valuation makes Musk the first person in history to hold a trillion-dollar fortune, at least in paper form — mainly through his stakes in SpaceX and electric carmaker Tesla. As of Friday afternoon, US business publication Forbes estimated Musk's updated net worth at around $1.1 trillion.

Investors valued SpaceX, which made a loss last year, at roughly 100 times its annual revenueImage: STAR MAX/IPx/picture alliance

How much did the record IPO raise?