With the return of Atlantis on July 21, 2011, the space shuttle program officially ended. Never fear. We'll be heading back -- and soon -- if these 10 players from the private sector space race have anything to say about it. See more »

There's a lot more out there than our measly solar system, and astronomers are becoming more adept at finding those worlds all the time. Here are 10 of their coolest discoveries. See more »

Blasting off from the shoulders of giants, China is slowly but steadily getting ready to conquer the next frontier: space. Here are 10 reasons why we're convinced it really might happen. See more »

By the time space shuttle Atlantis touched down after its final voyage in July 2011, a major shift in strategy for space exploration was already under way. What are NASA's newest programs? See more »

Do you know what that spacecraft is? It's one of the old Soviet space shuttles, and it never would have gotten built without the help of one the tiny countries on our list. Can you guess which one? See more »

Comic books have happily subscribed to the theory of multiple universes for decades. After all, how else could flying and leaping versions of Superman exist at the same time? In the real world, things are a little different. See more »

You probably self-identify as an Earthling, right? What if we told you that a few seed-bearing meteorites from Mars may have changed that little fact? See more »

If you take cosmic dust and add plasma ... do you get life? Findings suggest that plasma crystals may be the key to one of the universe's greatest mysteries: Is there life out there? See more »

Not by a long shot, self-centered earthlings. So the question is, exactly how many Earth wannabes are cruising around the universe and what are they like? See more »

On Sept. 14, 2011, NASA announced plans for the Space Launch System (SLS), the driving force behind the American space program for the foreseeable future. How much do you know about the future of American spaceflight? See more »