Gwynne Shotwell, long Elon Musk's second-in-command at SpaceX, spoke exclusively with CNBC ahead of her company's highly anticipated IPO.

This article is authored by Saswato R Das, astrophysicist and columnist, New York.

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

By Hannah Pedone and William Gavin