A scale model of the Cassini spacecraft, which will end its 20 year mission this year
After 20 years in orbit, NASA scientists are preparing the Cassini spacecraft for the "Grand Finale" – a spectacular, one-way trip into Saturn's atmosphere.
It will circle inside the rings of Saturn for five months, a total of 22 'fly bys', gathering data and images in the hope of finally unravelling the mystery as to how they were formed.
It will then be launched towards Saturn itself, burning up inside the planet's atmosphere, on September 15.
The unmanned Cassini has been orbiting Saturn for 12 years, and the mission was described as a "fantastic success" by Andrew Coates, professor of physics at University College London who was worked on the project for almost 30 years.
But it made arguably it's most goundbreaking discovery this year, when it found the ocean on Enceladus, one of Saturn's moons, was releasing large amounts of pure hydrogen gas.
Just as it does on earth, the presence of hyrdogen can support microorganisms without sunlight or oxygen – proving the moon is in some form habitable.
Prof Coates told the Sunday Times the discovery was "exciting".
"It shows the chemistry is there," he said. "It is prebiotic chemistry but it is…the building blocks of what could be used by life."
Cassini will become the first spacecraft to fly inside the gap between Saturn and its rings
The spacecraft discovered Enceladus was capable of supporting basic life forms
Cassini has travelled closer to Saturn then any other spacecraft in history, but next week it will get even closer.
Get Quotes on Home Insurance
It will be re-routed to inside the 1,800 mile gap between the planet and its rings, taking close-up images of the ring particles and mapping Saturn's gravity and magnetic fields.
Finally, this Autumn, Cassini will go out in a blaze of glory when it is propelled into Saturn's atmosphere at an astonishig 70,000 mph.