São os Vigilantes do Espaço? Aqui está um link para a amazon, talvez a arte da capa pareça familiar? link
Synopsis: The starship Genesis carries the last survivors of Earth on a desperate flight to a new home. But the ship is slowly disintegrating and the oxygen supply is running out -- it's a race against time and space. Out of the far reaches of the universe the Watchers of Space gather: Orion, the giant golden man; Starnight, the sword of power and magic; and Cygnus, the beautiful swan. Together they will help save the doomed ship. But no one on the Genesis will believe twelve-year-old William when he tells them of the Watchers' plan. For they no longer believe in anything -- not till they see William go spinning off into space...