"Those are signatures of such faster-than-light travel," Burnish went on. "As it happens, our ships leave a particular identifiable signature, like those you are looking at; those are the ripples left by the transit of known ships, all of them our own. The tracks of the Assassins' ships are quite different. If," he corrected himself, "the Assassins have ships of any kind at all; it is not clear what means they employed to travel through space. Those artifactual signatures, however, do exist. Or at least they did, because they were observed and identified at the time of the Withdrawal. Some of them I observed myself. Such artifacts may take thousands of years to dissipate, and it is for those that I seek."
"I see," Achiever said, and then it was his turn to correct himself. "That is, there is one point that is unclear to me. You spoke of some thousands of years, but we were inside the Core for much longer than that. Is it not likely that they will all have dissipated by now?"
"Oh, I hope not," Burnish said gloomily. "Because if the traces are gone we will have to start looking in places I do not wish to visit."
IV
As the days passed the lookplate displays thinned out. What had been an undistinguishable fog of white now became a sprinkle of countless single stars—white ones or golden, bright-hot blue or darkly smoldering red. It became possible to isolate individual stars among them and even to see which ones had planets, though none of the orbiting worlds Achiever detected seemed likely to have borne life. "Planets are common enough," Burnish assured his crew, "but life is not." Which, Achiever thought, made those ancient crimes of the Foe even worse; if life was rare, how much more horrid was its violent extinction?
At the beginning of each watch he made sure to display the plot of their ship's course in order to keep track of their progress; on the display the portion of their course they had already traveled was pale pink, the part yet to come in that shocking orange. But how slowly the pink line lengthened, and how depressingly long the orange remained!
When, in the old days, Achiever had found himself thinking about what might be Outside of the Core—which was not all that often, because he had had more than enough to think about in his everyday life on Three-Moon Largely Wet Planet, and in his regular job of flying back and forth to the other planets of other stars that were his usual destinations—when, that is to say, Achiever had thought about the matter at all, perhaps stimulated by those lessons that he had thought would never he put to use, on running the order disrupter—when, anyway, he had thought about what it would he like to really be Outside, the single thing that had seemed oddest to him was the incredibly rapid pace of events as they went on Outside the Core.
Now, however, he actually was Outside, and it did not seem that way at all. His fellow passengers did not flit rapidly about. They moved, as Heechee generally moved, sedately and not really very fast by any standard. Neither did those planets their instruments detected as they passed by spin dizzyingly around their primaries. Nor did the stars themselves wink when they were variables, nor visibly bloat and decay when they were supergiants.
But the difference in the rate of time was real enough on the personal level, and it made Achiever glum. Sometimes, as he burrowed into his sleep nest at the end of a shift, it occurred to him that he would sleep and wake and work and sleep again a dozen times in a time that, back on his own planet, would be measured by a single beat in either of his hearts.
Not only was time not passing faster than was normal. Sometimes it seemed to have stagnated entirely. Those were the times when Achiever woke to a work day that was different in no respect from the day that had gone before it. And when at last something did happen that hadn't happened a dozen times before, it was a development of an unanticipated kind.
Breeze had just brought him a meal. She reported that Burnish had once again refused his own food. "He is quite obsessed," she told Achiever as they shared their own spicy protein and sweet carbohydrates in the pretty pastel colors Breeze herself had chosen. "I think he wishes he could find that the Assassins are still roaming the galaxy somewhere. If it were me, I would have no such feelings. I would hope they had never stirred from their hideaway."
Achiever considered that, then gave the belly-writhing that was the Heechee equivalent of a shrug. "I suppose he knows what he is doing."
"I suppose," she agreed. "He seemed pretty worried, though." She chewed for a moment, then said reflectively, "Do I imagine this or is this food unusually tasty?"
"How surprising!" Achiever exclaimed. "I was on the point of making the same observation to you." And what was most surprising about that, to both of them, was that taste in CHON-food was not a variable. Unless the specifications were changed, which Breeze denied, the flavor of any particular form of CHON-food remained identically the same year in and year out. Amused at the thought, Achiever widened his mouth in the Heechee equivalent of a smile. He noticed that Breeze was smiling back at him. Charmingly. Almost enticingly....
Enticingly?
The muscles under Achiever's cheek skin suddenly stilled. Realization came; of course! The food wasn't unusually tasty, Breeze's smile no different from any other time. What colored everything for him—for both of them—was simply pheromones.
As soon as that thought crossed his mind he saw what he had not noticed before. The color of Breeze's skin had perceptibly darkened. In some places—the hollow of her throat, the eyelids—it had become almost purplish.
She was, without warning, coming into sexual season.
The mating customs of the Heechee were thoroughly civilized. When an available male and a sexually receptive female were proximate, they did not at once spring into copulation. The process took time. From the first signs of approaching receptivity to the culminating act seldom took less than a full day, sometimes—particularly when the female was young—as much as ten days, or even more. And Breeze was still quite young. So at this early stage nothing sexual passed between Achiever and Breeze. Well, nothing overt. Covert, however, you bet. When Breeze had finished eating the pale blue and crunchy part of the meal it was Achiever who unwrapped and handed her the sweet, gummy next course. When Breeze accepted it she allowed her skinny forefinger to rest for a moment on the back of his wrist.
Things might have progressed farther—a little—but that was the moment when Burnish chose to join them. He wore an expression Achiever could not read—sorrowful? Yes, probably that was one description, but also he looked even more worn and worried than usual. The muscles of his cheek working agitatedly, but he brought up short in the doorway, sniffing curiously.
Although jealousy is not a very marked Heechee trait, it would be untrue to suggest that Achiever failed to take note of Burnish's actions. But Burnish's evident worry was considerable—not to mention, Achiever thought to himself, that old Burnish must have been nearly past the maximally sexual phase of life. His worries overrode Breeze's pheromones. "I have made a decision," he said sternly. "We must accept the fact that there are no recent traces of the Assassins."
Achiever was not wholly distracted from his new concerns, but he gave Burnish a puzzled look. "But surely," he said, "that is welcome news?"
The old one paused, seeming to weigh the question in his mind, and, Achiever thought, Liking a lot longer to do it than seemed reasonable. At length he exhaled through his nose. "It is better news, perhaps, than if we had found evidence they had come out," he said meditatively, "but it means that you and I must do certain things that I would have preferred to avoid. Two of us must inspect the place where the Foe have hidden themselves, and make sure that they are still there."