English Across the Curriculum
Saturn is the sixth planet from the sun and the second-largest in our solar system. It is different from the other planets because of its rings, which were first seen by the Italian astronomer Galileo in 1610.
Because it spins so quickly, Saturn looks a bit flat, with a longer diameter through the equator than through the poles. Saturn is a very light planet - the only one that would float in a big body of water.
One Saturnian day lasts about 10 hours and it takes the planet almost 30 years to orbit the sun once. Because it moves so quickly around its axis there are strong winds that sweep the whole planet. At the equator they probably have a speed of up to 1700 km an hour. Because it is very far away from the sun, temperatures on the surface are abut -175 ° C.
Saturn's rings are the most fascinating feature about the planet. They are extremely wide, but very flat. They stretch to a distance of over 130,000 km from the planet's centre, but most of them are only very few meters thick. There are probably over 100,000 separate rings - made of icy rock and frozen gases. This makes them shine in the sunlight.
More than 50 moons have been discovered around Saturn. Some of them are only 20 km wide, others are bigger than our moon. Saturn's largest moon is Titan- even larger than Mercury. Not very much is known about this moon because it has a very thick orange-colored atmosphere made up of nitrogen and other gases. Underneath thick clouds there might be some form of water on Titan.
In 1997 NASA launched a spacecraft from Cape Canaveral, Florida with the aim of reaching Saturn. After a 7-year trip Cassini went into orbit around Saturn and sent a small probe to the surface of Saturn's biggest moon, Titan. In the past few years it has sent important data about Titan back to Earth. It also found out that liquid methane rains down on the surface of Titan, forming rivers and lakes of hydrocarbon.
Artist's image of Cassini spacecraft in orbit around Saturn
Image : NASA/JPL, Public domain, via Wikimedia Commons