Earth's atmosphere is what allows life to exist on this planet. Carbon dioxide gets a lot of media coverage because of its role in global warming, but in fact most of Earth's atmosphere is made up of the element nitrogen.
Major Components of the Atmosphere
The atmosphere is 78.08 percent nitrogen. Another 20.95 percent is oxygen. Together, nitrogen and oxygen make up 99.03 percent of the atmosphere. The other 0.97 percent is composed of several other chemicals whose volumes are measured in parts per million.
Minor Components of the Atmosphere
The atmosphere is 0.934 percent argon, 0.038 percent carbon dioxide and 0.0018 percent neon. Helium, methane, krypton and hydrogen all exist in the atmosphere in trace amounts
Nitrogen gas does not have any color or smell. In the atmosphere, it usually does not react. In fact, nitrogen is so inert that it was called "azote," which means "without life." In liquid form, nitrogen is odorless and colorless.
Nitrogen on Mars
In contrast to Earth, nitrogen makes up less than 3 percent of the atmosphere of Mars.
Explaining Nitrogen's Abundance
Overall, there is 10,000 times as much oxygen on Earth as there is nitrogen, but oxygen easily combines with other elements to become part of water and organic materials. Nitrogen does not easily combine with the materials that make up Earth and organic life, so a much larger percentage of all the nitrogen on Earth is in the atmosphere.