Jeff Bezos fulfilled his long-held dream of going into space on Tuesday, potentially paving the way for space tourism, which could be the next mission for the man who built one of the world’s largest business empires.

The Amazon founder spent a few minutes in space as part of a four-person crew on a reusable rocket built by his company Blue Origin, taking a small step toward his stated goal of building floating space colonies.

The journey comes just two weeks after he stepped down as CEO of Amazon, which grew from a garage startup to one of the world’s most powerful corporations. Bezos, 57, is still the CEO of the technology and e-commerce behemoth he founded 27 years ago. He founded Blue Origin in 2000 and has invested billions of dollars in the company.

Even after his divorce settlement, Bezos’ fortune was worth more than $200 billion, putting him at or near the top of the world’s wealthiest people.

He owns 10% of Amazon, a global behemoth with a presence in dozens of countries and 1.3 million employees.

Bezos, on the other hand, frequently recalls his humble beginnings: he was born to a teenage mother in Albuquerque, New Mexico, and adopted at the age of four by his Cuban immigrant stepfather. Bezos was drawn to computer science when it was in its infancy, and he studied engineering at Princeton University.

After graduation, he put his skills to use on Wall Street, rising to the position of senior vice president at investment firm D.E. Shaw by 1990.

But, four years later, he surprised his peers by leaving his high-paying job to launch, an online bookstore backed by his parents’ money.

In his farewell letter to Amazon employees, Bezos stated that the company achieved success by adhering to his mantra: “Keep inventing, and don’t despair when the idea appears crazy at first.” Bezos frequently recounts his early days at Amazon, when he packed orders himself and drove boxes to the post office, in public appearances.

Amazon now has a market capitalization of approximately $1.8 trillion. It forecasted $386 billion in annual revenue for 2020 from operations in e-commerce, cloud computing, groceries, artificial intelligence, streaming media, and other areas.

“Bezos has been a transformational leader… in book selling, retail, cloud computing, and home delivery,” said Darrell West, senior fellow at the Brookings Institution’s Center for Technology Innovation.

“He was a trailblazer who pioneered many of the modern conveniences we take for granted.”

According to Roger Kay, analyst at Endpoint Technologies Associates, Bezos “had an instinct for the right thing” in identifying the next market.

Kay stated that Bezos successfully transitioned the company from books to other merchandise to an online marketplace, as well as successfully building the cloud infrastructure that became the highly profitable Amazon Web Services.

Amazon outlasted its competitors by foregoing profits in the early years and “reinvesting everything into expanding,” according to Kay.

Bezos has been fascinated by space since watching the 1969 Apollo moon landing as a child, and he believes that space is critical to the planet’s future. He has discussed the possibility of humans living in space colonies, drawing inspiration from both science fiction writers and scientists.

“We have grown in size as a species and as a population, and this planet is still relatively small. We see it in climate change, pollution, and heavy industry. We are in the process of destroying this planet… we must save it.”

Bezos is stepping away from day-to-day Amazon management in order to devote more time to projects such as Blue Origin.

While Amazon has touted its $15 minimum wage and other benefits, critics claim that the company’s relentless focus on efficiency and worker surveillance has treated employees like machines. The Teamsters union recently launched an organizing campaign for Amazon employees, claiming that the company’s employees “face dehumanizing, unsafe, and low-pay jobs, with high turnover and no voice at work.”

Bezos appeared to address employee concerns earlier this year when he called for a “better vision” for employees following a bruising battle over a unionization vote in Alabama, which ultimately failed.

In his final letter as CEO, he set a new goal for the company to be “Earth’s best employer and Earth’s safest place to work.”