Above: the storm on Saturn (colour added by Nasa) marked by the red strip at the top of the planet
A gigantic storm erupted on Saturn, leading to a peculiar "burp" of ethylene gas in its atmosphere.
Saturn is a gas giant, and aside from a small core of iron, rock and nickel is made up mostly of layers of metallic and liquid gas, as well as an outer gaseous atmosphere.
Typically this outer atmosphere is very stable, but in rare instances can play host to violent storms.
These storms typically only happen once every 30 Earth years - or one year on Saturn - but researchers now say that a storm first detected in 2010 was "unprecedented" in its scale and violence.
Were it located on Earth, the storm would have encompassed all of North America from north to south, and would have wrapped around our planet's circumference many times over.
Starting in 2010, Nasa and the European Space Agency's Cassini spacecraft tracked the storm as it raged in the planet's atmosphere. It was the first storm of its kind to be witnessed by a spacecraft in orbit around the planet, a fact that allowed scientists a unique picture of the tempest below.
Cassini's composite infrared spectrometer (CIRS) instrument showed that "powerful discharge" from the storm sent temperatures 150 degrees Fahrenheit above normal.
A huge increase in the amount of ethylene gas in the atmosphere was also detected, back on Earth.
The strange appearance of this gas - and the giant storm which created it, is described in the November 20 issue of Astrophysical Journal.
"This temperature spike is so extreme it's almost unbelievable, especially in this part of Saturn's atmosphere, which typically is very stable," said Brigette Hesman, the study's lead author and a University of Maryland scientist.
The study added it was the "largest and hottest stratospheric vortex" ever seen in our Solar System - bigger than the Red Spot on Jupiter.Suggest a correction