Mars is a cold, dry, desert-like planet. But billions of years ago, scientific evidence suggests that it had a thick atmosphere, which kept it warm enough to support flowing water on its surface. So, what happened to the Red Planet, and could it happen to Earth?

Envision a time when hundreds of spacecraft are exploring the solar system and beyond. That's the future that NASA's ESCAPADE, or escape and plasma acceleration and dynamics explorers, mission will help unleash: one where small,