It's a layer of gas that surrounds the Earth, held in place by gravity. The atmosphere is made up of:
* Nitrogen (N2): The most abundant gas, making up about 78% of the atmosphere.
* Oxygen (O2): Essential for life, making up about 21%.
* Argon (Ar): An inert gas, making up about 0.9%.
* Carbon Dioxide (CO2): A greenhouse gas, making up a small but significant portion.
* Trace gases: Other gases like neon, helium, methane, and ozone, present in very small amounts.
The atmosphere is divided into several layers based on temperature:
* Troposphere: The lowest layer, where we live and weather occurs.
* Stratosphere: Home to the ozone layer, which protects us from harmful UV radiation.
* Mesosphere: The coldest layer, where meteors burn up.
* Thermosphere: A very hot layer, where the International Space Station orbits.
* Exosphere: The outermost layer, where the atmosphere gradually fades into space.
The atmosphere is vital for life on Earth. It provides us with air to breathe, protects us from harmful radiation, and regulates Earth's temperature.
