In truth, of course, the four hundred survivors, moving at lightning speed compared with the slow evolutions of the ice, were reconfiguring the space station in preparation for the Big Ride. The crippled Caboose was cut free and the components of the Shipyard moved forward. The big power reactor was brought in close to the Stack; from now on they would rely on ice to shield the rest of Izzy from its radiation. The eighty-one arklets arranged themselves into nine groups of nine and were tacked into place at the aft end, nozzles aimed backward. The structural works holding them into place at first were flimsy trellises on which spacewalkers could string cables, propellant lines, and hamster tubes. As soon as those were in place, the ice caught up with them, driven forward by the ceaseless operations of a giant Nat swarm, and the arklets were gradually cemented into place within a solid matrix of the fiber-reinforced ice known as pykrete.