Their glassite space helmets fogged, and their metal glove joints stiffened in the incredible surface cold: but the two men who could work finished their job. In the black sky glistened the little arclight of the sun, a sixteen-hundredth of the blaze that fell on Earth. Around them sulked Pluto's crags and gullies, sheathed with the hard-frozen pallor that had been Pluto's atmosphere, eons ago. From the wrecked cylinder of the scout rocket they had dragged two interior girders, ready-curved at t