Saturn is huge - more than 700 times the size of Earth. However, it's extremely light - if you could find a big enough ocean to put it in, it would float! That's because Saturn is mostly made of gases, including helium, the gases that make balloons float. But it's the rings around Saturn that give the planet its unique look. And for hundreds of years, it's those rings that people have found so attractive.
At first, Saturn looks like it has just one large ring. However, it actually has seven major rings, and each is made up of thousands of smaller ones. In total, the rings are more than 250,000 kilometers across - that's over two-thirds of the distance from Earth to our moon! In spite of this, the rings are quite thin. In fact, on average, they're less than 50 meters thick.
From Earth, the rings look like they are solid, with clear edges. However, this is deceptive. They are actually made from billions of particles of rock and ice. Some particles are as small as a grain of sand. Others are the size of mountains.
Scientists now know a lot about Saturn, but it still holds many mysteries. Because of this, 17 countries worked together to build a spacecraft, called Cassini. Launched in October 1997, Cassini started sending information from Saturn to Earth in 2004: Its images and videos have been extremely valuable. For example, in 2008, scientists found evidence that one of Saturn's moons might contain basic life forms.
All these years later, Cassini still sends daily information back to Earth. Using this data, scientists will continue to make exciting new discoveries for many years to come.
(From Reading Adventure 3)
According to the passage, which is NOT TRUE about Saturn?
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