See how the universe works with this motorized astrology set. The "sun" shines onto the nine planets as they orbit around it. The central tower and planetary support rods are black so that they "disappear" in a darkened room for a spectacular effect! Replace the solar dome with the star dome included to create a spectacular planetarium sky complete with major constellation names. In addition, the base features a special 1000-hour light bulb and planetary longitude marks so the planets can be set up to their correct positions. The Solar System model is powered either by four C batteries (not included) or by an optional AC adapter (not included).