A storm nearly the size of Earth is raging on Neptune, astronomers have discovered. The massive system, marked by bright clouds in an equatorial region where none have been seen before, stretches across 9,000km (5,592 miles). Scientists believe a huge high-pressure swirling vortex anchored deep in Neptune’s atmosphere may be responsible. Gases rising up in the vortex are thought to be cooling and condensing out to form clouds. Unlike the watery clouds on Earth, those on Neptune consist of methane.
Professor Imke de Pater, from the University of California at Berkeley, US, said: “Historically, very bright clouds have occasionally been seen on Neptune, but usually at latitudes closer to the poles, around 15 to 60 degrees north or south. “Never before has a cloud been seen at or so close to the equator, nor has one ever been this bright.” Such a large cloud system spanning many latitudes is most likely to have been created by a “dark vortex” super-storm, said the scientists.