All spinning objects, from carousels to planets, generate centripetal force. If a planet rotates too fast, that force can pull it apart. Before that happens, the planet will experience “flattening,” or bulging around its midsection, as seen in this animated illustration of a brown dwarf, Jupiter, and Saturn.
Video Credit: NASA/JPL-Caltech
Timing of Black Hole Dance Revealed by NASA Spitzer Space Telescope