The document discusses imaginary lines on maps used to describe locations on Earth's surface, such as meridians and parallels. It also describes the two movements of the Earth: its revolution around the sun, which takes 365 days and 6 hours, and its rotation on its axis, which takes 24 hours. Finally, it mentions that astronomers and astronauts make discoveries by studying objects in space and going into space themselves.

1. Study presentation
Planet Earth

2. Imaginary lines
On maps there are imaginary lines. We use these lines to
describe a location on the Earth’s surface.

3. Imaginary lines
On maps there are imaginary lines. We use these lines to
describe a location on the Earth’s surface.
> There are semicircular vertical lines from the North Pole
to the South Pole. These are called meridians.
> There are circular horizontal lines around the Earth.
These are called parallels.

4. Imaginary lines
We can combine longitude and latitude to
describe any location on Earth.
This is called a geographic coordinate.

5. The Earth’s movements
The Earth has two different movements:
revolution and rotation.

6. The Earth’s movements
The Earth has two different movements:
Revolution is the movement of the Earth around the Sun.
The Earth takes 365 days and 6 hours to make a
complete orbit of the Sun.
Rotation is the movement of the Earth on its own axis.
The Earth takes 24 hours to make a complete rotation.

7. The Earth’s movements
Revolution Rotation

8. Discoveries
Astronomers make discoveries by studying the Sun,
the Moon, planets and other objects in space.
Astronauts make discoveries by going into space.

9. Discoveries
People originally believed
that the Earth was flat.
But in Ancient History,
astronomers calculated it
was a sphere.
At the start of the 17th
century, the telescope
was invented.
They used lenses to help
us see objects far away.