"If we find lots of planets like ourswe'll know it's likely that we aren't alone, and that someday we might be able to join other intelligent life in the universe."
- William Borucki, principal investigator for NASA's Kepler mission
Planets in the hundreds of billions are likely caught up in the vast whirlpool of the Milky Way galaxy. From Earth, a lonely outpost on one of its spiral arms, we've begun to peer across the void. We can already make out, dimly, the light from planets orbiting distant stars. We've even tasted a few of their atmospheres by dissecting those faint traces of light.