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1. Planet Earth and its representation
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1.3. The existence of life on Earth
The existence of life on Earth depends on three main factors:
❚❚
The
distance from the Sun
which creates the appropriate temperature, not too
hot (Venus has an average temperature of 457 ºC) or too cold (Uranus has an
average temperature of –220 ºC).
❚❚
The presence of abundant
water
, where the first forms of life appeared. Water
supports life and is essential for survival.
❚❚
The existence of
an atmosphere
, a layer of gases which surrounds the Earth and
protects life from dangerous solar radiation.
Understand
1.
Look at the picture of the Solar System: Which planet is the closest to the Sun? Which is the biggest planet?
What other celestial bodies are in the Solar System?
2.
Explain in your own words the factors that enable life to exist on Earth.
3.
Listen and say the celestial body.
4.
Name the Earth’s satellite.
5.
What is the name of the galaxy our Solar System is in? What shape is it?
Create
6.
Find out what the asteroid belt is. Make an fact file with information.
7.
Find out how long each planet takes to revolve around the Sun once. Write the information in your notebook.
