• During a press conference, Maezawa reportedly said one of his main reasons for departing Zozo is to make time to train for a 2023 voyage around the moon with Starship : a new rocket system planned by SpaceX.
  • Maezawa also indicated he is planning to launch on a less ambitious spaceflight around Earth prior to his "#dearmoon" mission with SpaceX , founded by tech mogul Elon Musk .
  • SpaceX is working feverishly in South Texas and Florida to develop and test-launch prototypes of the system. Once complete, Starships may stand about 400 feet tall and be fully reusable.
  • Visit Business Insider's homepage for more stories .

Yusaku Maezawa, a key investor in SpaceX's next-generation rocket system, called Starship , plans to sell a 30% stake in his online fashion retail company, Zozo, to Yahoo Japan.

As part of the $3.7 billion tender offer, Maezawa will resign as CEO of Zozo, take home about $2.3 billion in cash, and maintain a 6% stake in the company he founded, according to Forbes .

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Koji Sasahara/AP Photo

Maezawa also said he wanted to launch on a less ambitious spaceflight prior to SpaceX's privately funded circumlunar voyage.

"Training to go into space will to take up much of my time," Maezawa reportedly said.

Maezawa first announced his bid for a weeklong Starship flight around the moon during a September 2018 presentation about the launch system by Elon Musk, SpaceX's founder and CEO. (It was then called Big Falcon Rocket , and has since been redesigned and renamed Starship, but the craft's core goals and capabilities remain similar.)

The fashion mogul, who is also an avid collector of art, named his experimental mission #dearMoon . He plans to handpick a crew that includes a "painter, musician, film director," and other artists and maybe a couple of astronauts to "inspire the dreamer within each of us" with the trip.

When a reporter asked Musk about his possible participation in the #dearMoon mission, he said (seemingly half-seriously), "maybe we'll both be on it."

Musk says progress on Starship is accelerating 'exponentially'

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Trevor Mahlmann/Reuters

If Starship is realized as currently envisioned by Musk, it will be a roughly 400-foot-tall , two-stage, steel-bodied vehicle. It'd also be the world's largest, most powerful, and paradoxically most affordable launch system because unlike any orbital-class rockets today it'd be fully reusable.

Musk said he may beat NASA back to the lunar surface with Starship and launch the first humans to Mars with the system, perhaps 100 at a time. Musk is also dreaming up an even larger version of Starship, the scale of which stretches the imagination.

Read more : SpaceX is eyeing these 9 places on Mars for landing its first Starship rocket missions

Maezawa would not disclose last year how much he's paying SpaceX for the trip, though his investment is going toward simultaneous Starship development efforts in Boca Chica, Texas , and Cocoa, Florida.

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Kimi Talvitie

SpaceX began building its first prototype, called Starhopper, at its Boca Chica launch site in late 2018 . After a few short test launches or "hops" in April and July , the vehicle which is a essentially a flying test-bed for SpaceX's new Raptor rocket engines made its last experimental launch from Texas in August . The final flight took Starhopper about 490 feet (150 meters) into the air before it landed on a nearby concrete pad.

SpaceX is now pushing to complete two orbital-class prototypes, called Starship Mk 1 and Mk 2 in Texas and Florida, respectively.

Newly released FAA documents refer to this part of Starship's development program as "Phase 3." As part of that phase, Musk tweeted on August 28 that SpaceX will try launching Starship Mk 1 about 12.4 miles (20 kilometers) above Texas in October before the company attempts an orbital launch "shortly thereafter."

Musk added that he would provide an update on the overall Starship development program on September 28. Previously, he said he would deliver that presentation from Boca Chica, Texas possibly to do so with a fitting backdrop.

"Starship Mk 1 will be fully assembled by that time," he said.

SpaceX representatives did not immediately respond to Business Insider's request for comment about Maezawa's latest remarks, the #dearMoon mission, or overall on the Starship development program.

NOW WATCH: Elon Musk's multibillion-dollar Starship rocket could one day take people to the moon and Mars

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