The Columbia space shuttle disintegrated while re-entering Earth's atmosphere due to damage caused from its launch. Here's why it went up but didn't come down.
The light in Earth's atmosphere may reflect signs of extraterrestrial life.
On this edition of A Moment Of Science, we check out some of the atmosphere's many layers.
Most of us take our oxygen-rich atmosphere for granted. Once upon a time, though, Earth's air was very different.