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The Outer Planets
The eight planets of our solar system are divided into two groups: inner planets
and outer planets. The outer planets are furthest from the sun and receive less light and
heat therefore they are the colder planets. They are Jupiter, Saturn, Uranus, Neptune and
Pluto, which is called a dwarf planet but not considered on of the eight planets. Except
for Pluto, these planets are all called the gas giants because they are composed entirely of
gases.
Jupiter, the fifth planet from the sun, is the largest planet in our solar system. It is
so large all of the other planets could fit inside it. You could fit eleven Earths along its
diameter and more than a thousand Earths inside it. Jupiter is made up of twice as much
materials as all the outer planets put together. Jupiter is so big and bright that you can see
it from Earth without a telescope. It has at least 16 moons orbiting around it, as well as
one very thin ring. It has a very active atmosphere that produces energy that causes a
huge circular storm, called the Great Red Spot, which has lasted for more than 300 years.
Jupiter makes one rotation in about 10 hours and orbits the sun in about 12 Earth
years.
Saturn is the sixth planet from the sun. It is best known for the beautiful system
of rings that circle the planet. Recently, it was learned that the circles are made up of ice
and rocky grains that orbit Saturn. Saturn also has a least 18 moons. It rotates in about
10 hours and orbits the sun in a bit more than 29 Earth years. Saturn is the second largest
planet, but it is very light. So light, in fact, that it could float on water.
Uranus, the seventh planet from the sun is the last planet you can see from the
Earth with out a telescope. Uranus is 3 ½ times the size of Earth. Uranus is a giant blue
ball of gas and liquid that has a least 15 moons and faint rings. Uranus lies on its side,
unlike other planets. A day on Uranus would last 10 hours and 45 minutes. That’s how
long it takes to spin around on its axis. However, it would take 84 Earth years for Uranus
to complete one orbit around the Sun.
Neptune is the eighth planet, and furthest gas giant. It looks like Uranus because
of its greenish color, but it is slightly smaller. Neptune can only be seen through a
telescope. Even then, it is very difficult to study. It has at least 8 moons and a faint ring,
as well as circular storms. It is also known to have the windiest orbit in the solar system.
Neptune makes on rotation in about 16 hours, and orbits the sun about 165 Earth years.
Not much is known of this distant planet.
Pluto, as of August 2006 is known as a dwarf planet, is the smallest and the
farthest from the sun. It is an icy planet so far out in space that it takes 248 Earth years to
orbit the Sun once. Pluto has one moon half its size. From Pluto, the sun looks like a
very bright star, and very little heat or light reaches it. Unlike the other outer planets,
Pluto is not made of gas, but instead has a rocky surface that is covered by frozen gases.
It takes about 7 Earth days to rotate and 249 Earth years to orbit the sun. Pluto has a
strange orbit—the shape of a long, flattened circle. Sometimes Pluto is closer to the sun
than Neptune.