The common room on the Sirian Pearl was the only place aboard ship where six people could meet face to face and still have a little central space to spare. The greater part of that central space was presently occupied by a holostage, and on that holostage the ship's computer was currently engaged in building an elaborate image-model of the local disturbances within the nebula. For the time being the other model, the one that showed the whole Milkpail, had been tucked back into the data storage banks.
Not that the six people of the crew were very often in the common room at the same time. At least two were usually at their duty stations, on watch. And each of them had a private cylindrical cabin adjoining one of the six duty stations. Like Domingo's cabin, the five others were little more than large padded barrels furnished with cots, communications and plumbing. Polly, like several other people, spent a fair amount of time in the common room, sitting beside the stage and watching the construction job with interest. With even greater interest, but less openly, she also watched Domingo, who was fanatically intent upon the model.
When the model displaying current local conditions was completed, the computer, on the captain's order, ran it through an extrapolation back in time. The dispersed explosions that were only dimly detectable in the nebula itself became smaller and clearer in the model as the extrapolation progressed. The tentatively charted tracks of disturbance assumed a sharper, more definite form. Now it was possible to have a much more precise view of what had happened here some days ago in the battle between the Space Force and the berserkers.
Here, at this side of the display, was where the Space Force ships had been during the first moment of confrontation. And over there on the other side had been the enemy, four or possibly five berserkers in all, strung out in a jagged line some hundreds of kilometers long that might or might not have been meant as a tactical formation. That much, the positions before tactical movement started, could be confidently read from the reconstructed cloud disturbances and the distributions of trace elements in the clouds. So could the positions at the start of fighting. The opposing types of weapons, when fired, and even the drive engines had left subtly different flavors in the resultant expanding gasses.
Combat maneuvers must have begun immediately when the opposing forces sighted each other—indeed, the human survivors had so reported. The course of events after the fight had started was harder to reconstruct. Domingo called for more sampling in selected areas. Armored people went out into space again, and the computer kept working.
Gujar, who had been so eager to sign on, began grumbling. "Why is he doing this? Has he ever told us exactly why?"
Iskander smiled faintly. "He's looking for a trail. Domingo knows what he's doing."
"Does he? I can see scanning the area for that. Not that there would be much chance of finding anything. But what difference does it make what the exact positions were of all the units?"
"We'll see." Iskander still sounded confident.
When the additional data gathered by a few more hours' work in space was fed into the computer, the pictured past became visible in greater detail. Two Space Force ships, as reported by the crews of the surviving vessels, had blown up with all hands lost. A couple of berserkers had also been destroyed—their climactic finishes were plain to see, marked by radii of flying debris. And at least one more of the enemy had been badly damaged.
The battered berserker had got away. It must have done so, because it was nowhere in the immediate vicinity now, and no image of its annihilation in a death-blast had been imprinted on the clouds. Evidently the other surviving berserkers had departed unhurt or only lightly damaged. There were faint and fading tracks for them, too attenuated to try to follow. But the badly damaged bandit had gone its own way, and it had certainly left a spoor behind it—a thousand times too thin for the eye to see, but evident to the technique of computer-analyzed sampling. A staggering trail of particles, a skein of what would have been smoke in atmosphere, a fading blaze of heat and radiation, led off toward an unexplored portion of the Milkpail into the heart of a white knot of nebula as wide as the orbit of the distant Earth.
"That's it! That's it. By all the gods, we'll get one of them now." The captain's voice was a hoarse whisper.
As soon as he had accepted the conclusion of the computer model, Domingo recalled those of his crew who were still outside the ship engaged in the task of gathering more data. Only two robots, attached to auxiliary power and shielding systems that let them cruise at a sufficient speed in space, remained outside still working at that task. The two mobile robots, Domingo calculated, should be enough to sniff out the trail, now that its origin was located. The moving fields of the ship would drag the small machines with her as she advanced.
The Pearl moved out again, running a little faster than before, hunting now with weapons ready. The model in the common room was continuously updated as the robots continued to take samples at distances of up to a few hundred kilometers from the moving ship and to telemeter the results in to the Pearl's main computer.
Excitement grew. Polly took her brief periods of rest grudgingly, afraid of what discoveries she might miss. Between rest periods she observed Domingo, snatched bites of food, stood watch in her turn and otherwise helped out where she could. She had seen an effort vaguely like this search attempted once before, by someone else, and not successfully. That time the quarry had been a lost ship, presumably willing to be found, not a berserker.
She said to him once: "You really know how to do this, Captain."
At the moment he looked happy and, despite the long hours of concentrated effort, almost relaxed. As if, Polly thought, everything were normal.
He said: "Better than the Space Force, anyway."
Following the trail was slow, hard work from the start. Within the first hour the track of the enemy became blurred, but the robots worked tirelessly and it was not lost. Gradually the job became easier, the gradient of increasing density of certain battle remnants in the nebula becoming better and better defined. The speed of the chase increased until at last it began to seem possible that they would someday catch something—unless, of course, their prey were to increase its speed as well.
The Pearl was already a billion kilometers into unmarked whiteness, far off such charts as existed for this portion of the nebula. Determining the location of the ship within it, even roughly, was no longer a trivial problem. Even the brightest suns could no longer be located with any certainty amid the thickening, muffling clouds of white, off-white and gray, the ever-changing pastel shades of perpetual interstellar dawns and sunsets. It was not unheard of for ships to simply vanish in the Milkpail, even in regions where no berserker activity had ever been reported.
There followed another blurring of the track, leading to a more prolonged slowdown. But this delay too was temporary, the trail firming again within a standard day.
Time passed quickly, at least for Polly, working, sleeping, watching. People off duty still took time for conversation in the common room, watching the model transform itself. And Wilma and Simeon still thought aloud, at least in the captain's absence, that the pursuit would ultimately prove hopeless.
But within two more days it was unarguable that they were still following the berserker's trail, and at an increasingly effective speed. The trail seemed fresher now, which meant that the enemy was probably no longer as far ahead as it had been.
That fact sank in. When the crew had begun this voyage, they had all still been in something of a state of shock. But by now that was wearing off. They had started to think about what they were doing: chasing a berserker.
And the pursuit could no longer be considered hopeless. Polly began to wonder what would happen when and if they actually did catch up to the wounded thing they were pursuing. Certainly the Pearl was heavily armed and her crew capable. But still.
Were they closing in on Old Blue? Polly, like most colonists in the Milkpail, had heard the name many times, and some of the legendary stories. She had a healthy respect for berserkers, but like Commander Gennadius she had never considered one of them more terrible than another just because someone had given it a name. Now, though . . . there had been something disturbing about the jagged, illogical-seeming shape of Leviathan in the recordings and the theatrical blue glow. But the blue light could be reasonably explained as an accidental effect of some kind of radiation. And as for the jagged form, who knew why berserker machines were sometimes built in one shape, sometimes in another? Randomness, that was always said to be one of their important concepts . . .
Whatever the reason for its peculiarities, it still seemed to Polly that one berserker, any berserker, just because it had acquired a name, ought not to be necessarily more frightening than another. Not that she had ever actually fought any of them, but . . . and whatever type of a machine it was that they were chasing, it was certain that it had already been seriously damaged; and that was reassuring.
Domingo had the six people of the crew divided into two watches now: three driving the ship, manning the weapons and studying the computer-modeled trail while the other three rested and slept and talked and waited for their turns on duty. In this way the hunt kept going hour after hour, one standard day after another.
The captain seldom slept or rested now. Polly, watching him, saw the chiseling of his face grow sharper; otherwise he seemed unaffected by lack of rest.
The folds of nebula flowed ever more thickly around the Pearl. This did not slow the progress of the ship, already limited by the need to find a trail and stay with it. But it did raise the possibility of ambush.
Gujar, operating the forward detectors on his watch, excitedly called in a sighting, and Iskander at the helm slowed forward progress. But the sighting proved to be a false alarm.
When the object appeared at close range it was seen to be a peculiar thing, some kind of natural life-construct, with stalactite-like formations protruding from it in all directions. It throbbed, faintly and slowly, with the working of the life within it. Not a single organism, the instruments indicated, but some kind of a composite form. The thing, or creature, or life-swarm, or whatever it was, appeared next on the close forward detectors and finally on the direct-viewing screens. Then it drifted by the Pearl at a range of only a few kilometers. It was vastly bigger than the ship. There was no indication that it was aware of the ship at all.
Relative to the nebular material immediately surrounding it, the object was moving at a significant fraction of the velocity of light, a speed that any ship or machine of equal size would have found practically impossible to attain.
No one on the ship had seen or even heard about anything like it before. At any other time the humans would have turned aside eagerly to investigate. But not now.
When the living conglomerate was out of sight, Simeon and Wilma made a tentative and ill-advised attempt to persuade the captain to turn around and go back to Base Four Twenty-five. They argued that the crew of the Pearl could now report to the Space Force what they had found regarding the berserkers and consider they had done a creditable job. Gennadius would thank them.
Domingo did not thank them for the suggestion.
The truth was that most of his crew, everyone but himself and Iskander, were growing increasingly uncomfortable in this weird place. Even to people who were more or less at home in the uncanny environment of the Milkpail Nebula, this thickening, curdling, mottled whiteness, engendering new monsters, was extraordinary. Among the uncomfortable majority the opinion was subtly gaining strength that it was, or ought to be, the job of the Space Force to carry on with this kind of pursuit.
Domingo was inflexibly opposed to any change of course and overrode the hints of opposition. He even touched in passing on the laws of mutiny. In port a crew might, and his usually did, have the right to vote on big decisions. In deep space the captain's word was law, and the law applied with redoubled force when the berserker enemy was near.
The captain did agree to send off one of their two expensive robot couriers, directed to Base Four Twenty-five, before he continued his pursuit of the damaged berserker.
The courier departed silently, carrying word of their discoveries, their present location and their intentions to Base Four Twenty-five. They hoped. The chance that it would succeed in getting there was hard to calculate.
Now there was only one usable courier left aboard. Here in clouds where radio was hopeless, it represented the only possible means of communication with the rest of humanity.
The pursuit of the wounded berserker resumed. More hours passed, adding up to another day. Tension grew aboard the ship as the trail became stronger, more clearly defined than it had ever been. Whatever was leaving the trail was undoubtedly closer ahead now than ever before. Sizable bits of debris, even fist-sized chunks of this and that, began to show up in the scans still being telemetered in from the outrider robots.
"That's berserker stuffing." Domingo said it softly, with obvious enjoyment.
A powerful blast centered somewhere ahead sent a silent but more-than-detectable Shockwave through the white nebula.
Chakuchin made a relieved sound. "It's blown itself up. That's it."
"We'll see." Domingo's intensity did not alter.
Inside the Pearl, whose forward velocity, even here within the buffeting whiteness, could be conveniently expressed as a fraction of the speed of light, the enormously slower Shockwave could be studied on the detectors for some time before it engulfed the ship.
But whatever might be, or might have been, at the center of the shock to cause it still could not be seen.
Domingo ordered acceleration. And more acceleration. Particles of matter, molecule-sized, pinged dangerously against the shielding fields that so far were managing to protect the hull from microcollisions at relativistic speeds. Indicators glowed with warning signals.
The captain ordered: "Give up the trail. Head for the center of that shock." The location of the center could be determined from the automatic recording of the event.
"Double alert for an ambush. Just in case."
On the screens of the forward detectors, the image of an object considerably bigger than the Pearl took shape and rapidly solidified. It was angular, irregular and metallic, about at the upper limit of size for effective travel within the nebula.
"Hold your fire!" the captain ordered sharply.
Whatever kind of a machine it was ahead of them, it was not Leviathan. The shape was as jagged as Leviathan's, but still totally wrong for that, if any of the descriptions and recordings of the monster were correct. Polly heard the captain sigh, a sound that might have come from the lips of a disappointed lover.
The second most obvious characteristic of the object they had just caught up with was the remarkable amount of fresh damage that it had sustained. The ruin looked too genuine and extensive to be any kind of trick. As they approached the wreck ever more closely there was hard radiation, too, wild and irregular in both intensity and kind, but always enough of it to suggest that there might be a small-scale nuclear meltdown in progress somewhere on the enemy.
It appeared that secondary explosions, delayed battle damage—or more likely a deliberate destructor charge, set off in anticipation of capture by the forces of life—had left this particular berserker unit, whatever it was exactly, drifting in a helpless condition.
The humans aboard the Pearl observed the enemy warily from a thousand kilometers' distance; then from a hundred; and then again from ten.
Simeon said, with the air of someone trying to establish an assertion as undoubted fact: "Now we've got to go back and report."
Polly, watching on her intercom, saw Niles Domingo's eyes turn to the big young man, one image glaring at another. The captain squelched Chakuchin's effort immediately: "We can't. We'll lose it if we do. Do you expect that we, or anyone else, will be able to find the way back to it again in this fog?" In another day or so the trail they had followed would have been completely dispersed by random drifting and other natural movements. There were currents in the nebula; it was at least as dynamic as an ocean of water on the surface of a planet.
"All right, then I suppose we finish it off. We have our missiles armed."
"They'd better be. But don't use any of them just yet."
"But what else can we do?" Chakuchin paused, as if realization had just come to him. "Are you expecting to send some of us over to board that thing? It may just be waiting to use its main destructor charge until something living comes close enough to be wiped out in the blast."
"I think it's already used whatever destructor charges it had left. And I'll lead the boarding myself, if that's what's bothering you. Can I talk two other people into suiting up with me? If not, I'll go alone. Polly, what about you?" The captain's eyes looked out from the little intercom screen and into hers. "We could use your technical expertise."
"I'll go," Polly heard herself agree at once. Then she trembled, thinking of her children. But she could not unsay what she had said. Not to Niles Domingo. She could silently curse the unasked-for fate that bound her to him, but it was her fate still, and she would not have changed it had she had the power.
Iskander, as usual, had not much to say, but he was plainly ready, even eager, to go where his captain led.
Gujar repeated Simeon's suggestion: "We could just fire away at it . . ."
But Domingo was silent this time, and this time the suggestion died without argument. The objections to it were too plain. Self-destruction was doubtless what the berserker had wanted to achieve, but something had gone wrong with the destructor charges.
That it had tried to destroy itself when capture by its enemy seemed imminent at least suggested that there was still something aboard that might constitute a valuable secret, perhaps even a clue to where the berserkers attacking the Milkpail colonies had their repair and construction base.
Conceivably there might even be human prisoners still living on that wreck. That there could be seemed doubtful, but berserkers did take prisoners sometimes for the information that could be gained from them, for living bodies and living minds on which to experiment.
Domingo was continuing to study the helpless-looking enemy, switching rapidly from one instrument of observation to another and back again. This was not Leviathan in front of him, but it represented the only immediate chance he had of getting closer to Leviathan. He mused aloud in his newly intense voice: "This is too damned strange. It's not like any berserker I ever saw or heard of before now. We can't miss the chance, we've got to go over there and see what we can find out from it."
Simeon suggested: "We've still got one courier. Let's send it off first, at least. Tell people where we are. Get some help out here."
Iskander shook his head. "I don't think so. If we launch our last robot courier here, we don't know that it's going to be able to find Base Four Twenty-five. Or that it'll ever be picked up by the Space Force anywhere. I'd say myself that the odds are pretty poor that a courier message from us here is going to get through." He smiled faintly. "Besides, couriers are expensive." It was the punch line of a standing joke.
Gujar said: "I agree. We might need the courier worse later on. I'd even say it's chancy as to whether we'll be able to find our way out of this ourselves; at least in any comfortable period of time."
And Domingo again: "Maybe a courier would be able to find its way to the Space Force somewhere. And if it found them, they might not be too busy to come and look at this thing. And if they did decide to come, and they did find their way here and saw it, they might be smart enough to realize its value. Or they might not. No, thanks. We're going to handle this ourselves. Even if they did agree it was valuable, they might still decide it would be better to fire away."
There was general agreement among the crew. People out here in the Milkpail depended, often enough, on the Space Force for their very lives. They also tended not to be overly impressed with that organization's abilities and accomplishments.
Simeon wavered. "Well, if you put it that way . . ." Wilma was silent.
"I do put it that way. Let's go."