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Saturn: Five things we've learnt in the last five years

SaturnImage source, Getty Images

It's the second biggest planet in our solar system and scientists have just made another amazing discovery about it.

Here are five fantastic facts we've learnt about Saturn in the last five years:

1. Saturn hasn't always had its famous rings

This is the most recent discovery about the planet.

We now know there was a time when Saturn didn't have its famous rings.

Scientists say they're younger than the planet itself which was formed 4.5 billion years ago.

Data from Nasa's Cassini mission has found the loops of icy particles are between 10 million and 100 million years old.

But they still say they're 'very young' as that's such a short time in the life of our solar system!

2. There could be life on one of its moons

Saturn's ice-crusted moon Enceladus might be a pretty good place to look for life beyond Earth.

In 2017 the Cassini probe sampled waters from a subsurface ocean which suggested the seafloor has hot fluid vents - places that here on Earth are known to be full of life.

It's not a guarantee that there are organisms on the little moon but it helps make a good case for returning to it to look for signs of them.

"We're pretty darn sure that the internal ocean of Enceladus is habitable and we need to go back and investigate it further," said Cassini scientist Dr Hunter Waite from the Southwest Research Institute in San Antonio, Texas.

3. Saturn might have gained a moon

Saturn already has over 60 moons but in 2014 scientists discovered what they thought could be the birth of a new moon in its rings.

It was informally named Peggy.

The evidence came from a black-and-white image of the outermost ring captured by the Cassini spacecraft.

At the time it was estimated that Peggy may be about half a mile wide and almost certainly made of ice.

Image source, NASA
Image caption,

In 2014 scientists thought they might have found Saturn's 63rd moon.

4. Part of the planet turned 'gold'

Scientists discovered a bit of a change at Saturn's northern pole in 2016.

It has a 'hexagon' which is essentially a rotating cloud pattern - its shape might be the result of large differences in the speeds of Saturn's winds.

Scientists found it had changed colour from blue to gold.

It's thought it was caused by seasonal changes on the planet and the amount of sunlight falling on the planet's poles.

Image source, Mary Evans Picture Library
Image caption,

A 'hexagon' at Saturn's northern pole changed colour.

5. Saturn's 'Death Star' moon might be wonky

One of Saturn's moons called Mimas looks a bit like the Death Star from Star Wars.

In 2014 scientists thought that it might be wonky on the inside!

A study looked at the moon's internal structure and found that it's either wonky or awash with water.

Researchers thought there could be two reasons why; either it has a vast ocean beneath its surface, or a rugby ball shaped rocky core.

Image source, NASA/JPL
Image caption,

One of Saturn's moons called Mimas has been nicknamed the 'Death Star' because it looks a bit like the Star Wars space station.