1. Saturn Diameter 9.4DE Rotation Period 10.5 hours
Orbital Period years
Distance from Sun 9.539AU
Orbit Eccentricity
Tilt degrees
Temperature -150C
Atmosphere hydrogen, helium, ammonia and methane
Gravity 1.16g
Moons >30
Visits Pioneer 11, Voyager 1 & 2, Cassini (July 04)
Saturn is one of the most spectacular sights in the SS. It is about 9 times the size of Earth, but has a very low density – so low that if you could find a lake big enough to drop Saturn into, it would float. The atmosphere is made of similar stuff to Jupiter, but the belts and zones are much fainter. Saturn is also giving out too much heat. It is mostly generated in the same way as Jupiter, by a small collapse under gravity. However, this isn’t enough to explain all of the extra energy. Something else must be going on, maybe the ‘raining out’ of helium close to the centre of the planet – the helium in the atmosphere all slowly collecting near the centre of the planet.
The rings are made of chunks of rock and ice, sized between a few cm and a couple of km. They are very thin, only about a km deep, but over km in diameter. They are kept in place by the movement of the planets close to them, which stop them from spreading any further. The moons near the rings are therefore called the “shepherd moons”. There is actually very little material in the rings – if you clumped it all together, the resulting body would only be about 100km across.

2. This is one of the most amazing images to ever be taken
This is one of the most amazing images to ever be taken. It would be impossible to take this picture from the Sun-side of Saturn as there is no way you could get the shadows to fall on the rings like that. The only position from which you can take this photo is beyond Saturn’s orbit. It brings it home just how far we’ve travelled.

3. Kept in place by “Shepherd Moons”
Saturn's Rings
Kept in place by “Shepherd Moons”

4. Voyager's
View of
Saturn's
Rings

5. Storms on Saturn

8. Principle Moons Tethys Mimas Enceladus Iapetus (1500 km) Dione
impact crater same size as Mimas
Enceladus
(500 km)
Brightest body in the solar system – fresh ice
Iapetus (1500 km)
Iapetus' brightness varies from that of Enceladus to coal black
Dione
(1000 km)

9. Titan Saturn's largest moon 5000 km
Covered a thick atmosphere which makes it effectively larger than Ganymede
But Voyager couldn't see the surface
Surface pressure 1.5 atmospheres
Cold atmosphere -180 degrees C
Comprised of Nitrogen (like the Earth)
Reactions with solar wind creates a thick smog in the atmosphere
Methane clouds occasionally form, and there may be methane oceans on Titan
Like Earth's Moon and the other Saturnian moons it rotates synchronously
This is a picture of Cassini-Huygens and Saturn’s biggest moon, Titan. Cassini-Huygens is currently on its way to Saturn, and is due to arrive in The first port of call will be Titan, which is one of the few moons to have an atmosphere. As such, it is one of the few places in the SS that might be able to support life. We don’t know what’s underneath Titan’s thick orange atmospheric layer, but we think that it might have a solid surface. Cassini will drop the Huygens probe onto Titan to monitor the composition and temperature of the atmosphere on the way down. Cassini will then continue on to study Saturn.

10. Cassini will arrive at Saturn this July!
The Huygen's probe will detach, enter Titan's atmosphere, and land on it's surface
The Cassini probe will radar map Titan's surface like Magellan did for Venus