Earth and Moon

The layer of air surrounding the Earth

The layer of air surrounding the Earth

The atmosphere It is the gas layer that surrounds the Earth's surface. It is formed by a mixture of gases that we call air.

In astronomy, we call atmosphere to a mixture of several gases surrounding any celestial object, such as the Earth, when it has a gravitational field sufficient to prevent them from escaping.

On Earth, the current mixture of gases, air, has developed over 4.5 billion years. The original atmosphere must have been composed solely of volcanic emanations, that is, a mixture of water vapor, carbon dioxide, sulfur dioxide and nitrogen, with hardly any trace of oxygen, very different from today.

Throughout this time, various physical, chemical and biological processes transformed that primitive atmosphere until leaving it as we now know it. The most important was carried out by algae and vegetables.

For living beings, especially for animals, the atmosphere is important because it houses the amount of oxygen we need to live. In addition, it filters the sun's rays that would be lethal to life and protects the Earth's surface from many external space agents, such as small meteorites.

In addition to protecting the planet and providing the gases that living things need, the atmosphere determines weather and climate.

In this chapter:

The Earth's atmosphere: The outer layer of the Earth is gaseous, of very different composition and density than the solid layers and… Read page Layers of the Earth's atmosphere: The layers of the atmosphere are the 5 regions into which the area of gases that surrounds the… Read page The circulation of the atmosphere: The atmosphere is the layer of gases that surrounds the Earth and that, thanks to its low density, can… Read page Atmospheric pollution: Astronauts return from their trips with a new mentality that It makes them feel more respect for the… Read Page