A less diffuse band of solar driftwood—the Asteroid Belt—was even easier to see, sandwiched between the orbits of Mars and Jupiter. Viewed from Voyager H’s oblique angle, the Asteroid Belt was a complex series of gaps and rings buried within an already complex series of gaps and rings.

In the center of the Belt’s largest gap orbited a mote of iced-over dust named Ceres. Because of her location, she had never, in the eyes of Earthly astronomers, attained the status of Uranus’s Miranda or Saturn’s Enceladus. Those bodies were actual moons, or worlds, whereas Ceres would forever be a lowly asteroid or worldlet, even though at one thousand kilometers in diameter, she was rounder than Enceladus and Miranda, and twice as large.

Far below the surface, Ceres Station had been growing for nearly twenty-six years, with the aim of one day occupying the whole interior of the asteroid, shell within shell, down to the very center. Isak had often dreamed that one day the spinning worldlet might become mobile and head out to the stars, as a few of the smaller asteroid colonies had been planning to do. He liked to imagine what the completed world of shells within shells would be like: spaced three hundred meters apart, the total inside acreage of the shells would easily exceed the total usable land surface of Earth. Worldlet, indeed! Ceres could become a world unto itself.

The vision that he had carried around inside himself— one which had seemed so unstoppable only a little while ago—was now a hopeless extravagance, stopped in its tracks by a development he would never have counted as a possible obstacle. He had hoped he might see the Ceres project completed when he was an old man. But no matter how long he lived—and he was no longer a young man—he knew he must, in his despair, prepare himself to accept the idea that he was not going to see humanity recover from this latest setback.

Against all the odds that had threatened to destroy civilization, his ancestors had somehow made it. Degrading universal empires had been avoided. The runaway fouling of the planetary nest had been halted. Most important of all, population growth had been brought under firm if not always humane control. Even with the expansion to the Moon and Mars, Ceres and Miranda, humankind’s numbers never again matched the preplague, preimmuno-genetic maximum. Isak’s people had realized—miraculously, it often seemed to him—that even as ascents to orbit finally became cheap, new worlds must never be viewed as relief valves for expanding, ravenous hordes who had overrun and exhausted their home. The deadly temptation to think of Earth as a disposable planet had been squelched with barely a decade to spare. One spring afternoon, the forests, rivers, and barrier reefs were coming back to life, and a new human kinship was arising throughout Sunspace. Then out of nowhere— out of the deep impersonal nowhere— came a bombardment that even the science fiction writers had failed to entertain.