By the time Space Shuttle Atlantis touched down after its final voyage in July 2011, bringing an end to NASA's 30-year-long space shuttle program, a major shift in the nation's strategy for space exploration was already underway. NASA's new plan involves using the fast-developing, private space-launch industry to carry out the low-orbital missions the space shuttles once performed. That approach will allow the U.S. space program to concentrate its efforts and funding on longer-range manned missions and unmanned probes that will venture deeper into the solar system.
In a 2011 speech, NASA Administrator Charles Bolden sketched out some of the details, including the agency's new Space Launch System, a launch vehicle similar to the Apollo's Saturn V booster that'll be the most massive rocket ever built, and the Multi-Purpose Crew Vehicle, a manned spacecraft capable of transporting four astronauts for space missions of up to three weeks in length. In addition to those programs, NASA also plans on a number of other robotic missions, including a quest to find evidence of conditions that would support microbial life on Mars [source: NASA].
What else is up NASA's sleeve? Here's a rundown of five of the more interesting new NASA forays into the cosmos.