'You don't sleep a lot': CEO of $8 billion company led a civilian crew into space while working 2 jobs simultaneously.

Jared Isaacman, a billionaire, spent 2½ years preparing for a historic 10-minute spacewalk, all while managing a nearly $8 billion company.

Isaacman, 41, led a SpaceX mission last month that included the first-ever all-civilian spacewalk, where he personally floated outside a Dragon space capsule. He is also the CEO of Shift4 Payments, a payment processing company he founded in his parents' basement in 1999 and grew to a market cap of $7.86 billion, as of Thursday morning.

"Isaacman, in an interview with CNBC Make It, reveals that he has had two parallel careers throughout his adult life, balancing his day job at Shift4 with his aerospace career. He admits that it doesn't allow for much sleep."

Isaacman, as both a CEO and father of two, has limited free time. However, he spent most of his leisure time preparing for a five-day trip that took him and his crew members beyond Earth's orbit, further than any humans have gone in over five decades.

Isaacman, with an estimated net worth of $1.5 billion, claims he remained actively involved in Shift4's daily operations during the two-plus years of training, which included the acquisition of Revel Systems for $250 million in May.

"Isaacman stated that it is a balance. He ate into a lot of his sleep while working at SpaceX, which meant spending many nights and weekends at the company. However, he was only out of contact for about five or six days during the mission."

Isaacman's second space venture was a SpaceX mission in 2021, where he financed and led the team that became the world's first all-civilian crew to reach orbit. This time, his training was more extensive, including preparation for deep-space issues like high radiation, micrometeoroids, and orbital debris.

Isaacman and his team tested out various versions of SpaceX's EVA spacesuits, including different joints, rotators, and stitching for the fingers, and practiced the spacewalk before actually performing it 800 miles above Earth.

"If you can't re-pressurize the vehicle, how do you get home?" asks Isaacman. "Unexpected issues arise. I'm not sure if there's been a flawless human spaceflight mission in the past 60 years."

The crew worked tirelessly during their five-day space mission, conducting numerous research experiments while keeping a close eye on the capsule and its systems. Despite the grueling schedule, Isaacman managed to get only a few hours of sleep, describing the experience as a "massive sleep deprivation event" for him and his crewmates.

While in space, Isaacman's thoughts were far from his day job, but he quickly returned to work after landing back on solid ground.

Isaacman states that he attended an investor event in Los Angeles just 48 hours after returning to Earth.

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