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from the show A Decade of Living in Space
• Saturn is the second largest planet in the Solar System
• Saturn is about 9.5 times wider than the Earth
• You could fit about 850 Earths inside Saturn
• Saturn is the sixth planet away from the Sun
• Saturn is twice as far away from the Sun as Jupiter
• The mean temperature in Saturn’s atmosphere is -125 degrees
• It takes Saturn 29.5 Earth-years to orbit once around the Sun
• However, one day on Saturn only lasts about 10 and a half Earth-hours
• Saturn has been visited by only four spacecraft, and 3 of these were just brief flybys
• Pioneer 11 was the first spacecraft to fly past Saturn, in 1979
• The Cassini spacecraft has been in orbit around Saturn since June 2004
• It took Cassini 7 years to make the journey from Earth to Saturn
• It takes light about 84 minutes to travel from Saturn to the Earth
The Structure of Saturn...
• Saturn is a gas giant, and is mainly made up of Hydrogen and Helium
• At the centre is a solid core made of rock and ice, that has about 5 Earth-mases of icy/rocky material
• The density of Saturn is lower than the density of water; it would float like an apple if you could find a pool large enough to hold it
• Saturn’s radius is 6,300km more at its equator than at its poles
• The winds in Saturn’s atmosphere can reach velocities of over 1,000 miles an hour near the equator
• Saturn’s rings were first observed by Galileo in 1610
• Saturn’s ring extend from 6,630 km to 120,700 km above Saturn's equator
• But they average less than about 100m in thickness
• The inclination of Saturn’s rings change relative to the Earth, so sometimes we see them edge-on, and sometimes almost face-on
• Saturn’s rings reflect a lot of light – so when viewed edge-on, Saturn is almost half as bright as when the rings are face-on.
• Saturn’s rings are not solid, but are composed of many individual ringlets
• The rings are made up of billions of particles of ice and rock, ranging in size from dust grains to small boulders
• Saturn’s rings are made from the debris created when a small moon was torn apart by Saturn's gravity about 100 million years ago
• Some very small moons of Saturn live in the gaps in the ring systems
• Recently a colossal new ring was identified around Saturn, stretching 50 times further into space than the more familiar rings
• Saturn has over 60 moons
• ... but only 13 of these have a diameter of more than 50km
• And only 7 have enough mass to be spherical
• Saturn’s largest moon, Titan, is the only moon in the Solar System to have a thick atmosphere
• And it’s larger than the planet Mercury
• We think some of the moons – such as Phoebe – are cometary nuclei captured into orbit around Saturn by its gravity
• Mimas has a huge impact crater that is almost a third of the diameter of the moon across. If there were a crater of an equivalent scale on Earth it would be wider than Canada.
• Titan has one of the richest stores of organic molecules in the Solar system
• Titan has rainfall cycle, with clouds, rivers, and lakes – not of water, but of methane
• Titan is the furthest celestial body on which we have landed a spacecraft
• Huygens is now the furthest human-made object ever to land on a celestial body.
• Enceladus has an icy surface, and reflects almost 100 percent of the sunlight that strikes it.
• Ice jets erupt from under this icy surface and eject water vapour, gas and grains of ice into space hundreds of km above the moon’s surface
• We think these jets are fed by a large liquid body of water under the ice
• These ice ‘geysers’ produce Saturn's faint but extended E ring.
• Iapetus has one face that is almost as bright as snow, and another as dark as coal
• Iapetus also has an unusual raised ridge around its equator that makes it appear like a walnut.