In June of 2011 ESA (European Space Agency) discovered a huge cloud of water vapor, which had been caused by Enceladus(Saturn's Moon)'s revolution around Saturn. An ESA observatory (Herschel Space Observatory) was the first to announce that they had found a huge cloud encircling Saturn. In 2005, NASA's spacecraft Cassini had seen that Enceladus was spitting out large amounts of water vapor and ice. The cloud is about 37,000 miles thick and more than 373,000 miles across. Despite its huge size, the cloud hadn't been seen before because water vapor shows up clear on most visible wavelengths.
The discovery of the cloud did not come as a surprise to many. A few of NASA's missions, including the Voyager and Hubble, had previously shown evidence that there may have been water-filled clouds around Saturn. ESA's Infrared Space Observatory then confirmed the existence of water in Saturn's atmosphere in 1997. In 1999 one of NASA's satellites also confirmed this again. The existence of this water around Saturn was at first, a mystery. Saturn's lower atmosphere does contain some water, but there isn't a way it could rise to the upper atmosphere. Enceladus was the answer; The water vapor was appearing from outside of the planet itself. Researchers built a model of what was happening and came to the conclusion that most of the water vapor gets tossed into space, but some of it gets frozen to Saturn's rings. A small percent of this water vapor gets through to Saturn's atmosphere, creating the cloud.
I found it interesting that with the technology we have today, this cloud is only just being discovered. I wonder how much bigger this cloud will get, and if it's going to eventually have any effect on the planet itself.
