A Supersecret Spacecraft Comes Back to Earth After Two Years

Marco Caceres, a space analyst with Teal Group, says the Air Force is most likely interested in having a surveillance platform that can "maneuver in orbit faster" than satellites. Darpa is also working on a new hypersonic "spaceplane" called the XS-1 that could offer quick access to space and launch payloads into orbit for less than $5 million per flight. "Quick, affordable, and routine access to space is increasingly critical for U.S. Defense Department operations," the agency said in its call for proposals for the spacecraft late last year.