Infinite Ryvius (1999)

Original title: 無限のリヴァイアス

An act of sabotage has sent a space station plummeting towards a dangerous phenomena known as the Sea of Geduld. With only hours to spare before the collapse of the entire station, a group of teens, training on-board the ship will seek safety aboard the Ryvius, an interstellar spacecraft hidden deep inside the station. With the adult crew and instructors dead, these young astronauts must rely on their training, courage and most importantly each other to prepare for the journey home.