Saturn's hexagon is a persisting hexagonal cloud pattern around the north pole of Saturn. The sides of the hexagon are about 13,800 km (8,600 mi) long, which is longer than the Earth's diameter. It rotates with a period of 10h 39m 24s, the same period as Saturn's radio emissions from its interior. However, the hexagon does not shift in longitude like other clouds in the visible atmosphere.Saturn's south pole does not have a hexagon, according to Hubble observations. But it does have a vortex, and there is also a vortex inside the northern hexagon.