Yusaku Maezawa, the billionaire entrepreneur who last month became the first Japanese civilian to travel to the International Space Station, said Friday he now plans a trip to the Mariana Trench, the deepest location on Earth.Maezawa revealed the exploration project at a press conference at the Foreign Correspondents' Club of Japan in Tokyo, saying that "it's been almost decided what kind of submarine will be used and how long the trip will be." Details of the plan will be announced later, he added.The billionaire said in a live radio broadcast from space last month that he next wanted to f…READ FULL ARTICLE