The third novel in the award-winning author's classic Galactic Center series is available once again. "A challenging, pacesetting work of hard science fiction that should not be missed" (Los Angeles Times). Nearly 100,000 years after first contact with the machines that dominate the universe, a few hundred humans survive. Trapped on Snowglade, a barren world near the center of the galaxy, people like Killeen of Family Bishop and his child Toby are primitive scavengers, homeless and hunted by the ruling "mechs." Then suddenly, a strange cosmic entity-neither organic nor cybernetic nor living matter-reaches out from a black hole to speak with Killeen. But can this fallen descendant of starfarers understand this alien being in time-and seize his only chance to save his family and mankind from final annihilation?