The 8 planets orbit around the sun, which conceals a wind-up motor. The Kosmos solar system operates entirely without electronics or batteries. The model is assembled from over 50 parts and is ready to go immediately, allowing the planets to move in four orbits around the large yellow center. With a diameter of 35 cm, the solar system fits in any child's room and can even stick to smooth surfaces thanks to a suction cup. The instructions explain every step with simple images, from assembly to useful tips and exciting background information, and an explanatory video provides additional help. The Kosmos experiment kit brings the solar system into the children's room, and with the ingenious wind-up motor, the planets orbit the sun solely through their own power.