The atmosphere is a mixture of gases that surrounds the planet. Without the atmosphere, life on Earth wouldn't be possible.

Layers of Earth's atmosphere: troposphere, stratosphere, mesosphere, thermosphere and exosphere.

Why is the sky blue, or sometimes red and orange? What causes rainbows? Find out here.

Dropsondes are launched from aircraft to measure temperature, wind, humidity and pressure as they fall through the sky.

In the stratosphere is the ozone layer, which keeps much of the harmful UV radiation from the Sun from reaching us on the surface.

Weather balloons carry instruments high in the atmosphere to measure wind, temperature, and humidity.

What kind of technology did scientists use long ago to measure the atmosphere? Discover the lengths people went to in order to explore the atmosphere.

A dangerous ozone hole started forming over Antarctica in the mid-1970s. But why? Learn how scientists and the world took action to save the ozone layer.