Elon Musk's SpaceX defies typical market buckets, and the IPO will give Wall Street another chance to value "strategic tech" like Palantir.

Charles Schwab, Fidelity, Robinhood, SoFi and Morgan Stanley's E-Trade are among the brokerage platforms making SpaceX shares available.

SpaceX long-anticipated initial public offering, which could value the company at about $1.75 trillion, has triggered intense demand from retail investors eager to gain exposure…