We can’t really see atmosphere, but if you look at light pouring through a window maybe you’ll see little particles floating in the air. And of course, when you feel wind, you are feeling the atmosphere moving around you.
When we are breathing in, we are breathing in the atmosphere, which is mostly nitrogen, not oxygen. There is water vapor in our atmosphere as well. All this atmosphere reaches out from Earth about 100 kilometers.
Atmosphere is made up of matter, since it’s made of “stuff.” It has an actual mass. Outside of our atmosphere, out in space, there is no air. We call space a vacuum, or an absence of atmosphere.
Our air can be polluted with other gases, such as smoke. Gases and particles that get picked up in the atmosphere (think of a dust storm) get carried in the wind and travel to other areas.
The “other” gases in our atmosphere are very important. Carbon dioxide, which humans breathe out, absorbs radiation, which may sound bad, but it is one of the things that enables life to exist on earth. It absorbs infrared radiation, which may sound like a bad thing, but it means it keeps the Sun’s heat on earth so that when the sun goes down at night, we don’t freeze.
Some scientists are concerned that if too much carbon dioxide gets trapped in the atmosphere then the atmosphere will trap too much heat and Earth will get too hot.
Images of Atmosphere