Maezawa and Hirano will travel aboard a Russian “Soyuz MS-20 spacecraft that is scheduled for launch on Dec. 8, 2021, from the Baikonur cosmodrome” in Kazakhstan.
Maezawa, made his fortune in online retail, also plans to participate in a 2023 mission around the moon aboard a Starship spacecraft of SpaceX, the Roscosmos rival of U.S. billionaire Elon Musk.
Maezawa and film producer Hirano, who will be documenting the mission, will begin pre-flight training in June at the Yuri Gagarin Cosmonaut Training Center in Star City, a closed town outside of Moscow.
The flight will last around 12 days and the crew will be led by Cosmonaut Alexander Misurkin.
It will be the first time that two of the three spots on a Soyuz space rocket will be occupied by tourists.
The last time Roscosmos took a tourist to the ISS was in 2009, with the flight of Canadian Guy Laliberte, co-founder of Cirque du Soleil.
The resumption of these tourist flights comes as Roscosmos lost its monopoly for ferrying crews to the ISS after a reusable SpaceX rocket last year successfully delivered NASA astronauts to space.