Izzy, which had been a complicated and hard-to-understand contraption even before all of this had happened, was now an utterly bewildering maze of modules, hamster tubes, trusses, and ships docked to ships docked to ships, "like a freakin’ three-dimensional domino game," as Luisa put it. The only way to get one’s bearings, looking at a rendering of the complex, was by picking out the rugged and asymmetrical shape of Amalthea at one end and the two tori at the other. Those were "forward" and "aft," respectively, and the axis between them was the basis for the traditional nautical directions of "port" and "starboard" as well as "zenith" and "nadir," which were space lingo for basically "up away from Earth" and "down toward Earth." If you arranged yourself so that your back was to the tori and your face toward Amalthea, with the "port" stuff on your left hand and the "starboard" stuff on your right, then your head would be aimed toward the zenith and your feet toward the nadir and the surface of Earth four hundred kilometers below.