Incandescence

She'd made a joke to Ruz about a rope, but it was exactly what she needed. She looked up at the tracker that Zak had assembled, wondering if she could use it somehow to lever him up. Then she noticed a sudden brightening, an aura of true, strong light seeping around the rock in the distance.

Roi hesitated, trying to imagine some way in which she might yet save them both. If they both died here, then it would begin to look as if the void itself was fatal, and Ruz would not be so foolhardy as to try to make the measurements himself. The chances were that nobody would leave the Splinter again.

Zak twitched, then tapped one claw against her.

"Run, you fool!"

She bolted for the crack and skidded over the edge, losing her grip by accident but then understanding that it was better this way, better to fall. She bounced painfully against the jagged rock, but kept her claws tightly closed, refusing to slow herself. The rock around her was brightening, and she could feel the heat of the raw, unfiltered Incandescence growing above her.

She hit the floor, bruised and aching, but forced herself to limp down the tunnel away from the searing light. Ruz appeared beside her and she climbed on to his back. She clung to him tightly as he sprinted to the intersection and around the corner.

He kept running until it was clear that they were sheltered by the rock, immersed in nothing but ordinary brightness. Roi listened to the pounding of their hearts. Ruz sounded almost as shaken as she was.

After a while, she spoke. "He was too weak to move. I couldn't shift him."

Ruz said gently, "He might have died in the Null Chamber instead, but it would have been soon, whatever he did. This was the risk he chose."

"I know."

"He did a lot in one lifetime. More than any of us. What he learned, what he taught, what he changed."

"That's true." Roi let the sadness sweep over her. In the end, there was only work, only the Splinter, only the next generation of hatchlings, and the next, on and on into the future. Nobody could live forever. But Zak had woken them all from a daze, woken them to a new kind of thought, a new kind of work, a new kind of happiness. Even if the Splinter itself had not been at stake, he deserved to be remembered for that.

Ruz said, "Are you badly hurt?"

"No. Give me one shift and I'll have my strength back."

"You want to go back there?" Ruz's tone was neutral; he wasn't going to pressure her to take Zak's place, but nor would he try to dissuade her.

"I've walked beneath the void once, I can do it again. And I'm sure there's something out there that we can track, something we can measure." Roi pictured the strange ribbon of colors stretched across the darkness; she had no idea what it was, but she had seen lights moving within it.

"There must be something simple," she said. "We have to keep searching for it."

Zak's body had been seared beyond recognition. Roi had seen many corpses in her life, most of them half-eaten by murche, but she had never faced a choice before about the fate of a friend's remains. Though everyone expected to be consumed by scavengers, as it was normally as inevitable as death itself, was it her duty to Zak to ensure that end? It seemed more fitting to leave him here, where the Incandescence had claimed him.

The tracker, made of metal and susk cuticle, was pitted and tarnished but appeared to have survived intact. Roi went to it and adjusted the aim, sighting a bright point of light at the edge of the colored arc. She took the clock Ruz had made for her from her right cavity, and held the moving wheels against her claw so she could time the occultation of the light by the tracker's wires.

As the light moved, its color changed smoothly. It didn't take long for it to cross the whole width of the band and vanish completely. Roi had no idea how to explain this peculiar behavior. Was the light now being hidden by something in the void — something opaque, like metal — or had it been destroyed?

She recorded the time it had taken for the light to cross a small portion of the view, but she didn't trust that number to tell her much about the Splinter's motion. The lights weren't merely changing color, they were moving apart as they flowed across the band. To expect the time it took for them to cross one thirty-sixth of a circle to be directly proportional to the whole journey seemed absurdly optimistic.

Ruz called to her anxiously, and she returned to the interior with plenty of time to spare. When she was safe in the shelter of the side tunnel she explained what she had seen.

"I have to go out again," she said. "Maybe we'll think of an explanation for all of this, and find some way to calculate the Splinter's orbital period from this data, but since we don't really know what we're measuring, the more observations I can make, the better."