And through the stars he made out the Cavity, a central bubble blown clear of gas by astrophysical violence, and within that the Baby Spiral, a swirl of stars and molecular clouds, like a toy version of the Galaxy itself embedded fractally in the greater disc. That was the center of the Galaxy, a place of layered astrophysical machinery. And it was all driven by Chandra, the brooding black hole at the Galaxy’s very heart.

This crowded immensity would have stunned a native of Earth—but Earth, with its patient, long-lived sun, out in the orderly stellar factory of the spiral arms, was twenty-eight thousand light-years from here. But Pirius had grown up with such visions. He was the product of a hundred generations grown in the birthing tanks of Arches Base, formally known as Base 2594, just a few light-years outside the Mass. He was human, though, with human instincts. And as he peered out at the stretching three-dimensional complexity around him he gripped the scuffed material of his seat, as if he might fall.

Everywhere Pirius looked, across this astrophysical diorama, he saw signs of war.

Pirius’s ship was one of a hundred green sparks, ten whole squadrons, assigned to escort this single Rock alone. When Pirius looked up he could see more Rocks, a whole stream of them hurled in from the giant human bases that had been established around the Mass. Each of them was accompanied by its own swarm of greenships. Upstream and down, the chain of Rocks receded until kilometers-wide worldlets were reduced to pebbles lost in the glare. Hundreds of Rocks, thousands perhaps, had been committed to this one assault. It was a titanic sight, a mighty projection of human power.

But all this was dwarfed by the enemy. The Rock stream was directed at a fleet of Sugar Lumps, as those Xeelee craft were called, immense cubical ships that were themselves hundreds of kilometers across—some even bigger, some like boxes that could wrap up a whole world.

The tactic was crude. The Rocks were simply hosed in toward the Sugar Lumps, their defenders striving to protect them long enough for them to get close to the Lumps, whereupon their mighty monopole cannons would be deployed. If all went well, damage would be inflicted on the Xeelee, and the Rocks would slingshot around a suitable stellar mass and be hurled back out to the periphery, to be reequipped, remanned, and prepared for another onslaught. If all did not go well—in that case, duty would have been done.