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2. The Earth in the Universe
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4.2.
Outer planets
The
outer planets
are very large and have a gaseous atmosphere. They are
surrounded by rings and their surface is in a gaseous or liquid state.
Key concepts
❚
The inner planets, Mercury,
Venus, Earth and Mars, are
small, with rocky surfaces
and they have few moons.
❚
The exterior planets, Jupiter,
Saturn, Uranus and Neptune
are big, with a gaseous
surface and they have rings
and many moons.
Apply
16.
Calculate how much
someone would weigh
on each of the other
planets in the Solar
System, if they weigh 50
kg on Earth.
Analyse
17.
Explain which planet
in the Solar System has
more characteristics in
common with Earth.
18.
Find information about
Jupiter’s four largest
moons. Make a table in
your notebook with the
most interesting data.
7
Jupiter
Saturn
Jupiter is named after the most
important Roman god.
Its atmosphere has cloud storms that
give the planet its characteristic colours.
Its average temperature is -120 ºC.
It has a ring made of dust particles.
It has 317.9 times the mass of Earth.
On Jupiter, we would weigh 2.64 times
more than we weigh on Earth.
Saturn is named after the Roman god of
agriculture.
Its atmosphere is composed of hydrogen
with some helium and methane. Saturn
is the least dense planet in the Solar
system (it would float in water).
Its average temperature is -125 ºC.
Saturn’s characteristic rings are made of
ice, rocks and dust.
It has 95.2 times the mass of Earth. On
Saturn, we would weigh 1.15 times more.
Uranus
Neptune
Uranus is named after the Roman god of
the sky.
Its atmosphere has hydrogen and
methane. Methane absorbs the red light
and gives the planet its characteristic
blue-green colour. Its average temperature
is -210 ºC.
Uranus is surrounded by eleven rings.
It has 14.6 times the mass of Earth.
On this planet we would weigh 1.17 times
more than on Earth.
Neptune is named after the Roman god
of the sea.
Its atmosphere is composed of
hydrogen, helium, water vapour, and
methane, which gives it a blue colour.
Neptune, like Jupiter, has storms and the
average temperature is -200 ºC.
Neptune is surrounded by four thin
rings made of dust particles.
It has 17.2 times the mass of Earth. One
Neptune, we would weigh 1.18 times
more.
