Science an Technology

Earth’s Atmosphere and Beyond!
he Earth is surrounded by a bubble of gas known as the atmosphere. Many of the other planets in our solar system are also enclosed in gas bubbles, but the mixture of gases on Earth is unique. This mixture is called air. We cannot see the air in our atmosphere and we cannot smell it—but the air is there. We can feel air as it blows across our skin, and we breathe it in and out of our noses and mouths. But what is air really, and is it the same everywhere? Air is made mostly of nitrogen and oxygen, with small amounts of argon, carbon dioxide, and other gases. Although air contains very little of these other gases, they can make a big difference in how easily we breathe. The quality of Earth’s atmosphere is not the same everywhere. In big cities, the air has more exhaust fumes from cars than in small towns. But air blows around and mixes, so that on a windy day the exhaust fumes from cars may seem to go away. In reality, the exhaust fumes are still there but are spread out over a greater space, and we don’t notice them as much. In the past few years, chemists and other

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Celebrating Chemistry
have very little energy and must wear oxygen masks for part of each day. No air is on the moon or in outer space. Astronauts must stay inside their spacecraft or put on space suits with tanks of air to breathe when they are away from Earth. Astronauts on Mars or Venus would find an atmosphere made of various gases, but it would not be air. There is no special name for the gas mixtures on other planets. The name “air” is reserved for planet Earth. Therefore, we simply refer to the gases surrounding Mars as the Martian atmosphere and the gases surrounding Venus as the Venutian atmosphere.

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scientists have been working on new fuels to reduce the amount of pollution in our atmosphere, so that we can breathe easier on hightraffic days. Many places on Earth have almost no air or very little of it. Although we cannot breathe at the bottom...