emergency party, having reached the place where the cables were broken, lost radio contact with Luna Base. After three in the morning we learned that this transporter had been attacked by laser and, as a result of several hits, now stood in flames. The driver and his assistant perished, but two of the crew—fortunately they were in suits, having got themselves ready to go out and repair the line—managed to jump free in time and hide in the desert, that is, the Mare Tranquilitatis, roughly here…” Achanian indicated with his ruler a point on the Sea of Tranquillity, some four hundred kilometers from the little crater of Arago.
“Neither of them, as far as I know, saw the assailant. At a particular moment they simply felt a very strong thermal blast, and the transporter caught fire. They jumped before the tanks of compressed gas went off; the lack of an atmosphere saved them, since only that portion of the fuel which was able to combine with the oxygen inside the transporter exploded. One of these people later died, in as yet undetermined circumstances. The other succeeded in returning to the construction site, crossing a stretch of about one hundred forty kilometers, but he ran and exhausted his suit’s air supply and went into anoxia. Fortunately he was discovered and is now in the hospital. Our knowledge of what happened is based entirely on his account and needs further verification.”
There was a dead silence. Pirx could see where all of this was leading, but he still didn’t believe it; he didn’t want to…
“No doubt you have guessed, gentlemen,” continued the dark-haired man in an even voice—his profile stood out black as coal against the blazing mercury landscapes of the moon—“that the one who cut the telephone cables and high-tension line, and also attacked the transporter, is our sole surviving Setaur. This is a unit about which we know little; it was put into mass production only last month. Engineer Klarner, one of Setaur’s designers, was supposed to have come here with me, to give you gentlemen a full explanation not only of the capabilities of this model, but also of the measures that now must be taken to neutralize or destroy the object.” The cadet next to Pirx gave a soft moan. It was a moan of pure excitement, uttered without even the pretense of sounding horrified. The young man was not aware of the navigator’s disapproving look. But, then, no one noticed or heard anything but the voice of the commodore-engineer.
“I’m no expert in intellectronics and therefore cannot tell you much about the Setaur. But among those present, I believe, is a Dr. McCork. Is he here?”
A slender man wearing glasses stood up. “Yes. I didn’t take part in the designing of the Setaurs; I’m only acquainted with our English model, similar to the American one but not identical. Still, the differences are not so very great. I can be of help.”
“Excellent. Doctor, if you would come up here. I’ll just present, first, the current situation. The Setaur is located somewhere over here”—Achanian made a circle with the end of his ruler around an edge of the Sea of Tranquillity—“which means it is at a distance of thirty to eighty kilometers from the construction site. It was designed, as the Setaurs in general were designed, to perform mining tasks under extremely difficult conditions, at high temperatures, with a considerable chance of cave-ins; hence these models possess a massive frame and thick armor… But Dr. McCork will be filling you gentlemen in on this aspect. As for the means at our disposal to neutralize it: the headquarters of all the lunar bases have given us, first of all, a certain quantity of explosives, dynamite and oxyliquites, plus line-of-sight hand lasers and mining lasers—of course, neither the explosives nor the lasers were made for use in combat. For conveyance, the groups operating to destroy the Setaur will have transporters of small and medium range, two of which possess light anti-meteorite armor. Only such armor can take the blow of a laser from a distance of one kilometer. True, that applies to Earth, where the energy absorption coefficient of the atmosphere is an important factor. Here we have no atmosphere; therefore those two transporters will be only a little less vulnerable than the others. We are also receiving a considerable number of suits, oxygen—and that, I’m afraid, is all. Around noon there will arrive from the Soviet sector a ‘flea’ with a three-man crew; in a pinch it can hold four on short flights, to deliver them inside the area where the Setaur is located. I’ll stop here for the moment. Now, gentlemen, I would like to pass around a sheet of paper, on which I will ask you to write clearly your names and fields of competence. Meanwhile, if Dr. McCork would kindly tell us a few words about the Setaur… The most important thing, I believe, would be an indication of its Achilles’ heel…”
McCork was now standing by Achanian. He was even thinner than Pirx had thought; his ears stuck out, his head was slightly triangular, he had almost invisible eyebrows, a shock of hair of indeterminate color, and all in all seemed strangely likable.
Before he spoke, he took off his steel-rimmed glasses, as if they were in the way, and put them on the desk.
“I’d be lying if I said we had allowed for the possibility of the kind of thing that’s happened here. But besides the mathematics, a cyberneticist has to have in his head some grain of intuition. It was precisely for this reason that we decided not to put
“The name suggests mythology, but it’s only an acronym, from Self-programming Electronic Ternary Automaton Racemic, racemic since in the construction of its brain we use both dextro- and levorotatory monopolymer pseudo crystals. But I guess that’s not important here. It is an automaton equipped with a laser for mining operations, a violet laser; the energy to emit the impulses is supplied it by a micropile, working on the principle of a cold chain reaction, so that the Setaur—if I remember correctly—can put out impulses of up to forty- five thousand kilowatts.”
“For how long?” someone asked.
“From our point of view, forever,” immediately replied the thin scientist. “In any case for many years. What exactly happened to this Setaur? In plain language, I think it got hit over the head. The blow must have been unusually strong, but, then, even here a falling building could damage a chromium-nickel skull. So what took place? We’ve never conducted experiments of this kind; the cost would be too great”—McCork gave an unexpected smile, showing small, even teeth—“but it is generally known that any sharply localized damage to a small, that is, relatively simple, brain or ordinary computer results in a complete breakdown in function. However, the more we approximate the human brain by imitating its processes, then the greater the degree to which such a complex brain will be able to function despite the partial damage it has suffered. The animal brain—a cat’s brain, for example— contains certain centers, the stimulation of which produces an attack response, manifested as an outburst of aggressive rage. The brain of the Setaur is built differently, yet does possess a certain general drive, a potentiality for action, which can be directed and channeled in various ways. Now, some sort of short circuit occurred between that motive center and an already initiated program for destruction. Of course I am speaking in grossly oversimplified terms.”
“But why destruction?” asked the same voice as before.
“It is an automaton designed for mining operations,” Dr. McCork explained. “Its task was to have been to dig levels or drifts, to bore through rock, to crush particularly hard minerals—broadly speaking, to destroy cohesive matter, obviously not everywhere and not everything, but as a result of its injury such a generalization came about. Anyway, my hypothesis could be completely wrong. That side of the question, the purely theoretical, will be worth considering later, after we have made a carpet of the thing. At present it is more important for us to know what the Setaur can do. It can move at a speed of about fifty kilometers an hour, over almost any terrain. It has no lubricating points; all the friction-joint surfaces work on teflon. Its suspensions are magnetic, its armor cannot be penetrated by any revolver or rifle bullet. Such tests have not actually been made, but I think that possibly an antitank gun… Of course, we don’t have any of those, do we?”
Achanian shook his head. He picked up the list that had been returned to him and read it, making little marks beside the names.
“Obviously, the explosion of a fair-sized charge would pull it apart,” McCork went on calmly, as if he were talking about the most ordinary things. “But first you would have to bring the charge near it, and that, I am afraid, will not be easy.”
“Where exactly does it have its laser? In the head?” asked someone from the audience.
“Actually it has no head, only a sort of bulge, a swelling between the shoulders. That was to increase its resistance to falling rock. The Setaur measures two hundred twenty centimeters in height, so it fires from a point about two meters above the ground; the muzzle of the laser is protected by a sliding visor; when the body is stationary it can fire through an angle of thirty degrees, and a greater field of aim is obtained when the entire body turns. The laser, as I said, has a maximum power of forty-five thousand kilowatts. Any expert will realize that this is considerable; it can easily cut through a steel plate several centimeters thick…”
