I think the best part of this is that they included a correction saying that one of the two people quoted as saying there were 'off world' vehicle said he never meant to imply 'other wordly', but the title stays: "Pentagon Has ‘Off-World Vehicles Not Made on This Earth’". 

  This because one material science expert could not figure out a material and went with: "If I don't understand it, it's from another planet".