Group C The Gas Giant Planets

Saturn is the sixth planet from the Sun. It was thought to be the furthest of the planets until the telescope was invented.

Second only in size to Jupiter, Saturn is made mainly of the light gases hydrogen and helium. 764 Earths would fit inside Saturn, but the gas giant weighs only 95 times as much as our rocky world. If you could put all of the planets in a pool of water, Saturn is the only one that would float.
Despite its size, Saturn spins once in a little more than 10 hours. Its spin is so rapid that it bulges outwards at the equator, making it look like a ball that has been squashed.
In a telescope, Saturn appears a pale yellow colour. It has no solid surface, so what we are seeing are clouds that appear as light and dark bands. These clouds are blown along by very strong winds. Much of the heat that drives these winds comes from inside the planet. Above the cloud tops is a flat, disk-shaped system of rings.
Much of what we know about Saturn has come from the NASA-ESA Cassini-Huygens mission. The Cassini orbiter has been in orbit around the planet since 1 July 2004. It has been exploring many of Saturn’s moons, especially planet-sized Titan. It has also sent back remarkably detailed pictures and other data about Saturn’s thunderstorms, the thousands of icy ringlets and the magnetic field.
On 14 January 2005, Europe’s Huygens probe parachuted onto the hidden surface of Titan. It was the first soft landing on another planetary satellite (apart from our Moon). Orange Titan was found to be a strange, icy world where methane rain fills lakes and rivers this is the gas giant planet.

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Uranus is the ancient Greek God of the Heavens - the
earliest supreme god. He was the father of Cronus also known as Saturn in Roman mythology) and of the Cyclopes and Titans (predecessors of the Olympian gods).

In Roman mythology Neptune was the god of the Sea. He is known as Poseidon in Greek mythology. The planet was probably named after the sea gods because of its deep blue color.
This is the symbol for Neptune:


Neptune is the eighth planet from the Sun and the fourth largest (by size) of the nine planets. Neptune is smaller in size but it's heavier than Uranus.


Neptune's blue color is the result of a gas called "methane" in its atmosphere. Like the other gas planets, Neptune has rapid winds trapped in "bands" of latitude and large storms. Neptune's winds are the fastest in the solar system, reaching 2000 km/hour!

At the time of Voyager's flyby, Neptune's most outstanding feature was the "Great Dark Spot" in the southern hemisphere. It was about half the size as Jupiter's "Great Red Spot" - about 1 Earth would fit into it. Neptune's winds blew the Great Dark Spot westward at 300 meters/second (700 mph)!

Voyager 2 also saw a smaller dark spot in the southern hemisphere and a small irregular white cloud that zipped around Neptune every 16 hours or so now. This feature is known as "The Scooter."

Recently, however, the Hubble Space Telescope (HST) showed that the Great Dark Spot has disappeared! Scientists think that it has either dissipated (like our storms do) or is currently being hidden by Neptune's atmosphere. Also, HST discovered a new dark spot in Neptune's northern hemisphere. This shows that Neptune's atmosphere changes rapidly.

Neptune also has rings. The Voyager 2 spacecraft showed scientists that Neptune indeed has complete rings with bright clumps. Like Uranus and Jupiter, Neptune's rings are very dark and very faint. Scientists still haven't figured out what they are made of yet.

Look for Neptune! Neptune can be seen with binoculars (if you know exactly where to look) but a large telescope is needed to see anything other than a tiny disk.

Jupiter is a giant gas planet which is made up of about 90% hydrogen and 10% helium.

~ Jupiter was first visited by the Pioneer 10 spacecraft in 1973. It was later visited by Pioneer 11, Voyager 1, Voyager 2 and Ulysses. The spacecraft Galileo is currently in orbit around Jupiter and will be sending back data for at least the next two years.

~ Jupiter is so big that you could cram 1,000 Earths inside of it! That's *mighty big*!

~ It is thought that Jupiter's "Great Red Spot" is a storm of swirling gas that has lasted for hundreds of years. Scientists are still unsure as to how such a storm could last for so long.

~ Jupiter has 16 known moons! There are four large "Galilean" moons, and 12 small ones

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