The NASA Orbital Test Vehicle is at Edwards Air Force Base . CNN 's Brad Lendon contributed to this report . It spent 674 days in space conducting experiments , military says . The military has spoken only in generalities about the spacecraft . Theorists speculate it 's a space bomber or a spy plane against the space station .
The NASA Orbital Test Vehicle is at Edwards Air Force Base . It spent 674 days in space conducting experiments , military says . The military has spoken only in generalities about the spacecraft . Theorists speculate it 's a space bomber or a spy plane against the space station .