Orbital flight. Missions to the mountains. Experiments in the water. The Kerbal Science Centre had done everything they could think of short of producing a Kerbal-rated mission to the Mun. To land a Kerbal on the surface of the Mun and to return him safely to Kerbin — that was the goal, said the director, before we leave the office on Friday. Once the engineers picked their jaws up off the floor, they got to work. Progress was slow, mostly because Jebediah was so excited that he wouldn’t get out…