Neptune is sporting a new spot, the first one identified in the 21st century. NASA’s Hubble Space Telescope confirmed the existence of the high-pressure system known as a dark vortex after bright clouds hinted at its presence.
“Dark vortices coast through the atmosphere like huge, lens-shaped gaseous mountains,” research astronomer Mike Wong, of the University of California at Berkeley, said in a statement. Wong led the team that analyzed the Hubble data.
“And the companion clouds are similar to so-called organic clouds that appear as pancake-shaped features lingering over mountains on Earth,” he added.
Both professional and amateur astronomers started seeing the bright clouds on the ice giant in July 2015. Companion clouds form when air flowing on the planet is disturbed and cast upward by a dark vortex. At high elevations, the gas freezes into methane crystals, forming clouds. This provided the first hint of a newly formed vortex, since the high-pressure systems are typically only visible at blue wavelengths.