π Planet Earth π Our planet
Air
π In short
Air is a mixture of gases that surrounds the Earth like a see-through blanket, called the atmosphere. We can't see it, but we feel it when the wind blows and see it move the clouds and leaves. Without air, no person, animal or plant could live.
π€© Did you know?
- The layer near the ground holds about 75% of the atmosphere.
- Argon and other gases make up only about 1% of air.
- When humidity reaches 100%, dew or fog forms.
- Sound travels through air, but in space, where there's no air, there's no sound.
π Find out more
π What is air made of?
Most air is a gas called nitrogen, and about a fifth is oxygen, the gas we breathe. There's also a little carbon dioxide, which plants need, water vapor and other gases.
π Wind is moving air
When the Sun heats air, it rises, and cooler air rushes in to take its place, so the wind blows. Wind pushes clouds, turns windmills and flies kites.
π‘ Air has weight
You might think air weighs nothing, but it presses on us from every side! And the higher we climb in the mountains, the thinner the air gets, so it's harder to breathe.
π― Let's keep the air clean
Smoke from factories, cars and fires pollutes the air. We can help by planting trees, and walking or cycling instead of driving for short trips.
𧩠Test yourself
1 Which gas in the air do we breathe?
2 What do we call moving air?
3 The layer near the ground holds about ?? % of the atmosphere.
4 Which picture shows βAirβ?
π Discover more
π· Picture sources: Wikimedia Commons
- NASA Earth Observatory Β· Public domain
