Few are as delighted by the pending market debut as the vibrant community of space enthusiasts who want to push discovery of the final frontier.

Gwynne Shotwell, the president and chief operating officer, is the adult-in-the-room foil to Mr. Musk as SpaceX prepares for a blockbuster initial public offering.

Gwynne Shotwell, the president and chief operating officer, is the adult-in-the-room foil to Mr. Musk as SpaceX prepares for a blockbuster initial public offering.

The $135 share price means Elon Musk’s rocket maker is poised to exceed the 2019 initial public offering of Saudi Aramco in both valuation and money raised.