New study show that an icy moon around Saturn is showering rain water onto its home planet, creating a vast halo of water vapor around the ringed world. Enceladus is the only known moon in the solar system which influence the chemical composition of its parent planet.Enceladus has a frigid, icy surface but an active interior, particularly at its south pole. In this dynamic region, geothermal activity is concentrated at four trenches that are dubbed “tiger stripes” because of their distinctive surface markings. These fissures, which measure approximately 80 miles (130 kilometers) long and 1.2 miles (2 km) wide, form icy geysers that spew plumes of water vapor into space. Enceladus expels roughly 550 pounds (250 kilograms) of water vapor every second through its tiger stripe jets.
Observations from the European Space Agency’s Herschel space observatory show that this water raining from Enceladus creates a doughnut-shaped ring of water vapor around Saturn.The total width of the water vapor ring is more than 10 times the radius of Saturn, yet it is only about one Saturn radius thick. So with the help their new observations scientists in finaly could solve the mystery about the origin of water in the upper atmosphere of Saturn.