A Nasa spaceprobe has spotted a monster hurricane two-thirds the diameter of Earth raging on the planet Saturn.

Just like our hurricanes, the giant storm has a well-developed eye and is ringed by towering clouds. But scientists are baffled because it is not behaving like a hurricane should.

The Cassini spacecraft, in orbit around ringed planet Saturn, recorded a three-hour movie of the storm’s winds blowing clockwise at 350mph.

The hurricane, 5,000 miles wide, lies at the planet’s South Pole. Clouds spiralling from its central ring are up to five times higher than those from similar storms on Earth.

Saturn’s hurricane is different from terrestrial storms because it is locked to the pole instead of drifting around. It has also formed without an ocean beneath it because Saturn is a gas world. On Earth the walls of cloud form when moist air rises from the sea.

Andrew Ingersoll, of Cassini’s imaging team at the California Institute of Technology, Pasadena, said: “It looks like a hurricane, but it doesn’t behave like a hurricane. Whatever it is, we’re going to focus on the eye of this storm and find out why it’s there.”

The space scientists hope that peering into the eye of the hurricane will allow them to see deeper into cloud-shrouded Saturn than ever before. The distant world, second biggest planet in the solar system, lies around a billion miles from Earth. Photo: Nasa.