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Until 10 years ago our knowledge of the Saturnian system was limited to three brief flybys by three Nasa spacecraft: Pioneer 11 in 1979, Voyager 1 in 1980 and Voyage in 1981.

But that all changed when Cassini-Huygens arrived on 30 June 2004 and entered orbit around Saturn, the first manmade spacecraft ever to do so.

Since then it has made numerous groundbreaking discoveries, including lakes on the moon Titan and giant storms on Saturn, and today it celebrates a decade orbiting the planet.

Today the Cassini spacecraft, artist's illustration shown, celebrates 10 hugely successful years in orbit around Saturn. During this time it has dramatically increased our knowledge of this fascinating planetary system, revealing vast bodies of liquid on the surface of Titan, giant storms on Saturn and much more

When Cassini arrived in 2004 its primary mission was only scheduled to last four years.

Since then, having survived the extreme environment it inhabits, it has been granted three mission extensions that have seen it perform unprecedented science.

It has remained in orbit around Saturn for one third of the planet's 30-year trek around the sun, observing its seasonal changes in the process.

The mission is jointly run by Nasa, Esa and the Italian Space Agency (ASI).

Its total cost is about £1.9 billion ($3.26 billion), of which the U.S. supplied 80 per cent, Europe 15 per cent and Italy 5 per cent.

It was launched on 18 October 1997 and, during its seven-year trip to Saturn, it flew by Venus, the Moon and Jupiter.

The highlight of its initial year at Saturn was arguably the release of the Huygens probe onto the surface of Titan.

On Christmas day 2004 this probe, 4.3 ft (1.3 metres) across, was released and, on 14 January 2005, it entered the atmosphere of Saturn's largest moon Titan.

That same day it became the first spacecraft ever to touch down on a body in the outer solar system and, in the process, spotted surface features that indicated the presence of liquids.

Since then Titan has been studied in depth by Cassini, and in so doing it has revealed lakes and seas on its surface, in addition to its thick atmosphere.

This has led some to dub it the most Earth-like place in the solar system, aside from our own planet of course.

But that is just scratching the surface of Cassini's many accomplishments.

SATURN'S MOON TITAN AND THE CASSINI SPACECRAFT

Titan is Saturn's largest moon - with a radius of appropriately 1,600 miles (2,574 kilometers). It's bigger than planet Mercury and is the second-largest moon in the solar system.

In January 2004 the Huygens probe landed on its surface and sent back images (right).

The atmosphere of Titan is largely composed of nitrogen; minor components lead to the formation of methane and ethane clouds and nitrogen-rich organic smog.

The climate - including wind and rain - creates surface features similar to those on Earth, including dunes, rivers, lakes and seas (probably of liquid methane and ethane), and deltas, and is dominated by seasonal weather patterns as on Earth.

Launched in 1997, Cassini has been exploring Saturn and its series of moons since 2004.

On Saturn, a full year is the equivalent to 30 Earth years, meaning Cassini has only been able to observe a third of a Saturn year.

Since 2004, Saturn and its moons have seen the seasons change from northern winter to northern summer.

Cassini revealed that Titan's surface is shaped by rivers and lakes of liquid ethane and methane (the main component of natural gas), during its initial flybys.

Scientists are interested in Titan because its atmosphere is most like that on Earth. Titan is said to resemble a frozen version of Earth, several billion years ago, before oxygen entered the atmosphere.

This false-color mosaic, made from infrared data collected by the Cassini spacecraft, reveals hydrocarbon lakes at Titan, the only other place in the solar system that is known to have stable liquid on its surface, though its lakes are made of liquid ethane and methane rather than liquid water

After 10 years at Saturn, the spacecraft has beamed back to Earth hundreds of gigabytes of scientific data, enabling the publication of more than 3,000 scientific reports.

'Having a healthy, long-lived spacecraft at Saturn has afforded us a precious opportunity,' said Linda Spilker, Cassini project scientist at Nasa's Jet Propulsion Laboratory in Pasadena, California.

'By having a decade there with Cassini, we have been privileged to witness never-before-seen events that are changing our understanding of how planetary systems form and what conditions might lead to habitats for life.'

Among its discoveries Cassini helped to increase our understanding of how water can form on other celestial bodies.

This was most notable from the discovery of icy crovolcanoes erupting on the moon Enceladus.

Once about every 15 years, the sun shines on the edge of the ring plane and the northern and southern sides of the rings receive little sunlight. Cassini measured the thick, long shadows from this rare event to determine the heights of structures within the rings, as shown in this picture of Saturn's 'B ring'

This incredible image of Saturn, called 'The Day the Earth smiled', was taken by Cassini on 19 July 2013. In it Saturn is lit up by the sun behind it, revealing glorious detail in the planet and its rings. At about the 4 o'clock position, just below the rings, is a faint dot that is Earth as seen 898 million miles (1.44 billion kilometers) away

While Cassini was originally approved for a four-year study of the Saturn system, the project's engineers and scientists had high hopes that the mission might carry on longer, and designed the system for endurance.

The spacecraft has been remarkably trouble-free, and from an engineering standpoint, the main limiting factor for Cassini's lifetime now is how much propellant is left in its tanks.

The mission owes a great deal of its longevity to skillful and efficient piloting by the mission's navigation and operations teams.

'Our team has done a fantastic job optimizing trajectories to save propellant, and we've learned to operate the spacecraft to get the most out of it that we possibly can,' said Earl Maize, Cassini project manager at JPL.

'We're proud to celebrate a decade of exploring Saturn, and we look forward to many discoveries still to come.'

It has been a decade since Cassini first soared over rings of ice and fired its engine to fall forever into the embrace of Saturn. Today the Cassini mission celebrates 10 years of exploring the planet, its rings and moons. It arrived for a four-year mission but has since been continuously extended, although it will end in 2017

Saturn's polar regions have surprised scientists with a the presence of a long-lived hexagonal-shaped jet stream in the north (pictured) and two hurricane-like storms at both poles. The driving forces of each remain a mystery. In the remaining three years of Cassini's mission, scientists hope to learn more of their properties

Enceladus's massive plume (pictured) was such a surprise that mission designers completely reshaped the mission to get a better look. It became even more important when Cassini found evidence of water-based ice in the plume, making Enceladus one of the most exciting science destinations in the solar system

The mission, however, will come to a conclusion in 2017.

By this year Cassini will no longer have enough fuel to maintain its orbit around Saturn.

So, to prevent it accidentally crashing on and contaminating one of the moons, Nasa will send the spacecraft diving into the atmosphere of Saturn.

In the process the spacecraft will be crushed and destroyed, but not before it returns fascinating information about the gas giant's cloud tops.

And this last hurrah will mark the end of an era; currently there is no future spacecraft planned to visit Saturn.

With interest instead focusing on Mars, Jupiter and other moons like Europa, it may be some time before Saturn gets another mission of its own.

Some areas of the scientific community, though, are hoping form a mission to Titan.

And they may just get their wish if, before its plunge into Saturn's atmosphere, Cassini spots something on the surface that piques the interest of the whole world.