Darkness fell before she reached it. The hanger—it was a pun on "hangar," a term from Old Earth aviation—was a big hollow pod hanging on the end of a tether that, just now, extended far up into space. At its opposite end, thousands of kilometers above, was another hanger just like it, serving as a counterweight. The two hangers formed a bolo, rotating around each other to keep the tether stretched tight between them. The bolo orbited the Earth just like any other satellite, the difference being that the height of that orbit, and the length of the tether, had been tuned so that on every rotation—or, as it appeared from Kath Two’s point of view, each long stride across the heavens—the hanger on the low end would swing down into the uppermost reaches of the atmosphere and seem to hover, almost still, for a minute. Somewhat analogous to the way that a runner’s foot will remain planted on the ground, unmoving, for an instant during each stride, even though the runner is traveling swiftly. In any case it came low enough and went slowly enough that a glider, pumped to great velocity and brought high into the atmosphere by the power of the mountain wave, could catch it and match it.