The Mova Rotating Moon 4.5 in. diam. Globe is intriguing for budding scientists or experienced, scholarly professionals. It's a great educational tool, especially for those who enjoy exploring the various moon surface features. Most of all, observers are drawn to the rotation of this orb, which turns silently on its own when exposed to natural or artificial light, sitting upon its beautiful, engravable acrylic base. No wires or batteries - this globe rotates on the same principles of physics as Earth itself. A magnet inserted in the core of the globe propels rotation when the globe sits in a window or next to a light source. About Mova Globes: By using a unique design, highly efficient solar cells, and the Earth's magnetic field, Mova has created a stunning line of globes that appear to rotate even though firmly rooted in place. This effect is created by placing a smaller globe inside the outer acrylic shell and filling the space between with a clear fluid. The inner globe floats in the center, while the solar cells and magnetic drive cause it to rotate. The graphic features of the inner globe are magnified by the acrylic shell and fluid, making them appear to be on the outer shell; this causes the illusion of movement of the entire globe. Ultra-efficient solar cells mean that your globe will rotate even in low light, using the energy from your room's lighting. This automatic movement, coupled with stunning graphics, makes the Mova globe a perfect choice for any home or office. Elegant, clear acrylic stand. Beautifully detailed moon globe. Powered by solar energy and Earth's magnetic field. Operates without any batteries or electric power. Measures 4.5 diam. inches.