It's the kind of once-in-a-lifetime chance: a Japanese billionaire is opening up a private lunar expedition to eight guests from across the world.

Yusaku Maezawa is an online fashion tycoon who was named as the first human to reserve a seat on SpaceX's lunar spacecraft in 2018. He paid an unspecified amount for the mission, which is due to begin in 2023 at the earliest, had previously claimed that he intended to invite six to eight artists to accompany him on the Moon journey.

Then on Wednesday, he posted a video on social media in which he said, "I'm inviting you to join me on this mission. Eight of you from all around the world. I have bought all the seats, so it will be a private ride."

Maezawa told his original plan of welcoming artists developed when he came to feel that any individual doing something artistic should be considered an artist. Applicants will only need to follow two conditions, according to the Japanese entrepreneur: being able to "push the envelope" creatively and supporting other crew members in doing so. He also said that 10 to 12 people will be on board the spacecraft, which will rotate around the Moon before coming back to earth.

To be eligible for a seat on the mission, prospective astronauts must pre-register by March 14, with initial screening taking place by March 21. The next steps like an "assignment" and an online interview -- have no timeframes set but final appointments and checkups are set for late May 2021, as per Maezawa's website.

SpaceX founder Elon Musk also said in the video posted by Maezawa- "I'm highly confident that we will have reached orbit many times with Starship before 2023 and that it will be safe enough for human transport by 2023. It's looking very promising."

He added, "The mission will be the first private space flight beyond Earth's orbit" and "We expect people will go further than any human has ever gone from planet Earth."

Maezawa has also hit the headlines for publishing an online ad for a girlfriend to accompany her on a SpaceX flight, only to terminate the search after receiving nearly 30,000 applications. He is better known for his quirky remarks and luxurious lifestyle, which includes a taste for luxury paintings, which was estimated at $1.9 billion last year, making him one of Japan's wealthiest citizens.