The Earth is the planet we live on. It is the third planet from the Sun and the only one known to support life, thanks to its liquid water, its blanket of air called the atmosphere, and a suitable temperature that is neither too hot nor too cold.
Shape and movement
The Earth is almost a sphere, slightly flattened at the poles and bulging at the equator. It has two main movements. Rotation is the spin on its axis once every 24 hours, which causes day and night. Revolution is its journey around the Sun once every 365¼ days, which, together with the tilted axis, causes the seasons.
Key idea
Rotation (spinning) gives us day and night; revolution (orbiting the Sun) gives us the year and the seasons.
Lines and zones
Imaginary lines help us describe places on Earth. Lines of latitude run east–west (the Equator is 0°), while lines of longitude run north–south (the Prime Meridian is 0°). The Equator divides the Earth into the Northern and Southern Hemispheres.
Remember
- Latitude lines run east–west and measure distance North or South of the Equator.
- Longitude lines run north–south and measure distance East or West of the Prime Meridian.
- Malaysia lies near the Equator, so it has a hot, wet equatorial climate all year.
Example
Because Malaysia sits close to the Equator, it has high temperatures, heavy rainfall and no cold winter season, unlike countries far to the North or South.
These imaginary lines and movements together explain why different parts of the world receive different amounts of sunlight, and why the length of day and the weather can change so much from one country to another.