Features all 10 planetary orbits. The motions of the planets, their relative sizes and distances from one another are illustrated in this attractive model. This model enables the student to "see" and "feel" what the Solar System looks like. The student will be able to visualize the physical relationships between the planets and the sun, and realize a better understanding of the various motions of the planets. When used with Ptolemaic System, all the problems of the real and apparent motions become clear. Stainless steel arms. Instruction book, ?Worlds in Motion," is included.