"Wunderwelten" by Friedrich Wilhelm Mader is a science fiction novel from the early 20th century. Six adventurers embark on an extraordinary space voyage aboard the spherical ship Sannah, powered by a revolutionary anti-gravity drive. Their journey takes them from the Moon's far side to Mars's dying civilization, through Saturn's rings, and beyond—swept by a comet past Neptune into interstellar space. They discover Alpha Centauri's paradise planet Eden, where an advanced society lives in harmony with nature, before returning home to plan new expeditions.