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(^2) SATURN
Sixth from the Sun, and second
largest, is pale yellow Saturn. Its
distinctive feature is its ring system,
which is made of billions of pieces
of dirty water ice. Saturn is mainly
hydrogen and helium with a rocky
core. It has a large family of moons.
(^4) MERCURY
Mercury is a dry ball of rock,
covered by millions of impact
craters. It is the smallest planet,
the closest to the Sun, and has the
widest temperature range of any
planet. During the day it is baking
hot, but at night it is freezing cold.
(^6) NEPTUNE
Neptune is the most distant, coldest,
and windiest of all eight planets.
Like Uranus, it is made mainly of
water-, methane-, and ammonia ices
with an atmosphere of hydrogen-
rich gas. It is encircled by a thin ring
system and has a family of moons.
(^8) EARTH
The only place known to have life
is Earth, the largest of the rocky
planets and third from the Sun. It
is also the only planet with liquid
water. Movements in Earth’s crust
are constantly changing its surface.
Earth has one moon.
(^3) URANUS
Nineteen times the distance of
Earth from the Sun, Uranus is a
cold, turquoise world bounded
by a layer of haze. A sparse ring
system encircles the planet’s
equator. Uranus is tilted on its
side, so that its rings and moons
seem to orbit it from top to bottom.
(^5) VENUS
Second from the Sun, Venus is
the hottest planet. This rock world
is permanently covered by thick
cloud that traps heat and makes
it a gloomy planet.
(^7) MARS
Sometimes called the “red planet”,
Mars is the outermost of the rocky
planets and a cold, dry world. It
has polar ice caps, giant volcanoes,
frozen desert, and deep canyons,
formed in the distant past.
Mars has also two
small moons.
(^9) DWARF PLANETS
The Solar System has five known dwarf
planets – small, roundish objects that
orbit the Sun amongst other objects.
Ceres orbits between Mars and Jupiter
within a belt of rocky asteroids, while
Pluto, Haumea, Makemake, and Eris are
icy worlds that orbit beyond Neptune
in a region called the Kuiper Belt.
The ring pieces, which range
boulders several metres across, in size from dust grains to
reflect sunlight well and make
the rings easy to see
A thin layer of high-altitude
cloud gives Saturn’s banded
atmosphere a muted appearance
PLANET SCALES
Jupiter, fifth planet from the Sun,
is much larger than all the other
planets. It measures 142,984 km
(88,846 miles) across and is made of
about two and a half times as much
material as all the other planets put
together. The seven other planets
and the five dwarf planets are
shown here roughly to scale.
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The blue colouring
of Uranus is due
to methane in
its atmosphere
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