• The Solar System is full of:
Comets, asteroids and dust and gas
• Everything in the Solar System orbits around the
The PlanetsThe Planets
• The 8 planets are divided in two groups:
Inner Planets: Mercury, Venus, Earth and
Outer Planets: Jupiter, Saturn, Uranus and
They are separated by the Asteroid Belt
• Is the planet closest to the
Sun, and it is the eighth
largest of the nine planets
• Is a small, rocky planet. It is covered with
• One of Mercury's largest features is called the
Caloris Basin. It is about 1300 km across
• Mercury is so close to the Sun, and so small,
that it has only a very small atmosphere.
• It has no moons
• Venus is a small, rocky
planet, very similar to Earth
• Its surface is very hot (400ºC) due to the
• It has yellow clouds not made of water
(like the ones here on Earth). Instead, they
are formed from a poison called sulfuric
• Mars is a small, rocky planet
which is cold and lifeless.
• Mars has permanent ice caps
at both poles made up mostly of solid carbon
• Very strong winds and vast dust storms
sometimes blow through the entire planet for
• Mars has two tiny moons which orbit very close
to the surface. Their names are Phobos and
• Jupiter is the largest planet
which is made up of about
90% hydrogen and 10%
• Jupiter has 16 known moons! There are four
large "Galilean" moons (Io, Gaminedes, Calixto
and Europe) and 12 small ones
• Jupiter has rings like Saturn's, but much smaller
• It has a “Great Red Spot”, 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.
• Saturn is a giant gas planet
which is made up of about
75% hydrogen and 25%
helium. It's most famous for its thousands of
• Saturn's rings are made up mostly of water ice.
The origin of the rings of Saturn is currently
• Saturn's rings are extraordinarily thin. Even
though they measure about 250,000 km across,
they're no more than 1.5 kilometers thick.
• Saturn has 18 known moons
• Uranus is a giant gas planet which
is made up of mostly rock and
• It has been visited by only one spacecraft, Voyager 2 on
Jan 24 1986.
• Uranus spins differently from most planets. It seems to
be tilted "sideways" instead of right-side up. At the time
of Voyager 2's passage, Uranus' south pole was pointed
almost directly at the Sun.
• Uranus has 15 known moons. Voyager 2 discovered 10
small moons in addition to the 5 large ones already
known. It is likely that there are many more tiny moons
within the rings.
• Neptune is a giant gas planet
which is most likely made up of
various "ices" and rock
• 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
• Neptune has 8 known moons; 7 small ones and a large
moon called "Triton."