The 14-year mystery behind the water on the planet Saturn is now solved. Researchers have found that the planet's sixth largest moon named Enceladus is the source of a huge halo of water steam around Saturn.

The planet known for its spectacular rings is the only one of its kind found till now whose own moon showers rain water onto it on a regular basis. According to scientists, this is an activity unique to Saturn. When it comes to Earth, "no significant quantities of water enter our atmosphere from space."

Icy moon Enceladus

Enceladus, the sixth largest moon of the planet Saturn, has an active interior. However, its surface is cold and icy, mainly at its south pole. According to researchers, this is the region where geothermal activity is concentrated at four trenches that are dubbed "tiger stripes." It's these jets from which Enceladus throws approximately 550 pounds (250 kilograms) of water vapor every second.

Researchers said that the thrown out water from the icy moon forms a doughnut-shaped ring of water vapor around Saturn that almost equals to five Saturns in width and about as thick as one-half a Sat­urn.

Since the water vapor is translucent to visible light, it has not been detected until now, despite its huge size. However, the European Space Agency's Herschel space observatory, tuned to infrared wavelengths and succeeded in unveiling the mystery.

Researchers said that a large amount of Enceladus's rain water either gets lost in space, freezes on Saturn's rings, or perhaps falls onto other moons of the ringed planet, but what does remain to reach Saturn is enough to explain the source of the water found in its upper atmosphere.

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