Catch a wisp of the solar wind, take a picture of the early universe and study the climate of Mars with this guide to active unmanned missions. MORE >>
Take a look back at the milestones in space exploration, including such historic launches as the Mercury-Redstone 3, Apollo 11 and John Glenn's return to space aboard the space shuttle Discovery. MORE >>
Go back in time to see what the Earth was like when its surface was hotter and wetter, and watch flora and fauna evolve into modern plants and animals. MORE >>
