It's a gas! Air consists of nitrogen and oxygen and lots of empty space.
Where's the best place to keep warm, a mountain top or a valley? Well, it just depends...
Don't worry, there's plenty of air to go around, even in tight spaces.
Human flight began as early as the 18th-century when scientists learned how to harness the power of different gases.
Despite weighing tons, clouds seem to free-float in the air. How do the billowy marvels stay up in the sky?
Most of us take our oxygen-rich atmosphere for granted. Once upon a time, though, Earth's air was very different.
It may sound paradoxical, but warm spells and flurries often go hand in hand.
When looking at a picture of the sun, how could you tell whether or not it's rising or setting?
A baby grabs the string of a single helium balloon and floats right out of its baby carriage. Why can't people really float into the air using helium balloons?
Planning on climbing Mount Everest? You might want to plan to be gasping for air. Learn more on this Moment of Science.