Imperial Earth

  "Now of course there were several good reasons for this neglect. In the first case, it's impossible to study these waves on Earth — they don't get through the ionosphere, and so never reach the surface. You have to go into space to observe them."

  "But for the very longest waves, it's no good merely going up to orbit, or to the other side of the Moon, where CYCLOPS was built. You have to go halfway out to the limits of the Solar System."

  "For the Sun has an ionosphere, just like the Earth's — except that it's billions of times larger. It absorbs all waves more than ten or twenty kilometers in length. If we want to detect these, we have to go out to Saturn."

  "Such waves have been observed, but only on a few occasions. About forty years ago, a Solar Survey mission picked them up; it wasn't looking for radio waves at all, but was measuring magnetic fields between Jupiter and Saturn. It observed pulsations that must have been due to a radio burst at around fifteen kilohertz, corresponding to a wavelength of twenty kilometers. At first it was thought that they came from Jupiter, which is still full of electromagnetic surprises, but that source was eventually ruled out, and the origin is still a mystery."

  "There have been half a dozen observations since then, all of them by instruments that were measuring something else. No one's looked for these waves directly; you'll see why in a moment."

  "The most impressive example was detected ten years ago, in ‘66, by a team doing a survey of Iapetus. They obtained quite a long recording, rather sharply tuned at nine kilohertz —that's thirty-three kilometers wavelength. I thought you might like to hear it..."

  Duncan consulted a slip of paper and carefully tapped out a long sequence of numbers and letters on the Minisec. Into the anechoic stillness of that strange room, Karl spoke from the grave, in a brisk, businesslike voice.

  "This is the complete recording, demodulated and speeded up sixty-four times, so that two hours is compressed into two minutes. Starting now."

  Across twenty years of time, a childhood memory suddenly came back to Duncan. He recalled listening out into the Titanian night for that scream from the edge of space, wondering if it was indeed the voice of some monstrous beast, yet not really believing his own conjecture, even before Karl had demolished it. Now that fantasy returned, more powerful than ever.

  This sound — or rather, infrasound, for the original modulation was far below the range of human hearing — was like the slow beating of a giant heart, or the tolling of a bell so huge that a cathedral could be placed inside it, rather than the reverse. Or perhaps the waves of the sea, rolling forever in unvarying rhythm against some desolate shore, on a world so old that though Time still existed, Change was dead...

  The recording, as it always did, set Duncan's skin crawling and sent shivers down his spine. And it brought back yet another memory — the image of that mightiest of all Earth's creatures, leaping in power and glory into the sky above Golden Reef. Could there be beasts among the stars, to whom men would be as insignificant as the lice upon the whale?

  It was a relief when the playback came to an end, and Karl's surprisingly unemotional voice commented: "Note the remarkably constant frequency — the original period is 132 seconds, not varying by more than point one percent. This implies a fairly high Q — say..."

  "The rest is technical," said Duncan, switching off the recording. "I merely wanted you to hear what the Iapetus survey team brought home with them. And it's something that could never have been picked up inside the orbit of Saturn."

  A voice he had not heard before — young, rather self-assured — came out of the air behind him.

  "But this is all old material, familiar to everyone in the field. Sandemann and Koralski showed that those signals were almost certainly relaxation oscillations, probably in a plasma cloud near one of Saturn's Trojan points."

  Duncan felt his façade of instant expertise rapidly crumbling; he should have guessed that there would be someone in his audience who would know far more about his subject than he did — and possibly, for that matter, even than Karl.

  "I'm not competent to discuss that," he replied. "I'm only reporting Dr. Helmer's opinions. He believed that there was a whole new science here, waiting to be opened up. After all, every time we have explored some new region of the spectrum, it's led to astonishing and totally unexpected discoveries. Helmer was convinced that this would happen again.

  "But to study these gigantic waves — up to a million times longer than those observed in classical radio astronomy — we must use correspondingly gigantic antenna systems. Both to collect them — because they're very weak — and to determine the directions from which they come.

  "This was Karl Helmer's Argus. His records and sketches contain quite detailed designs. I leave it to others to say how practical they are."

  "Argus would look in all directions simultaneously, like the great missile-tracking radars of the twentieth century. It would be the three-dimensional equivalent of CYCLOPS — and several hundred times larger, because it would need to be at least a thousand kilometers in diameter. Preferably ten thousand, to get good resolving power at these ultralow frequencies."

  "Yet it need contain much less material than CYCLOPS, because it would be built in Deep Space, under weightless conditions. Helmer chose as its location the satellite Mnemosyne, outermost of Saturn's moons, and it seems a very logical choice..."

  "For Mnemosyne is twenty million kilometers from Saturn, well clear of the planet's own feeble ionosphere, and also far enough out for its tidal forces to be negligible. But most important of all, it has almost zero rotation. Only a modest amount of rocket power would cancel its spin entirely. Mnemosyne would then be the only body in the universe with no rotation at all, and Helmer suggests that it might be an ideal laboratory for various cosmological experiments."

  "Such as a test of Mach's principle," interrupted that confident young voice.

  "Yes," agreed Duncan, now more than ever impressed by his unknown critic. "That was one possibility he mentioned. But back to Argus..."

  "Mnemosyne would serve as the core or nucleus of the array. Thousands of elements — little more than stiff wires — would radiate from it, like — like the spines of a sea urchin. Thus it could comb the entire sky for signals. And incidentally, the temperature out around Mnemosyne is so low that cheap superconductors could be used, enormously increasing the efficiency of the system."

  "I won't get involved in the details of switching and phasing that would allow Argus to swing its antenna spines electrically — without moving them physically — so that it could concentrate on any particular region of the sky. All this, and a great deal more, Helmer had worked out in his notes, using techniques evolved with CYCLOPS and other radio telescopes."

  "You may wonder — as I did — how he ever hoped to get such a gigantic project started. He planned a simple demonstration, which he was certain would provide enough evidence to prove his theories."

  "He was going to launch two equal, massive weights in exactly opposite directions, each towing a fine wire, several hundred kilometers long. When the wire had been completely deployed, the weights would be jettisoned — and he would have a dimple dipole antenna, perhaps a thousand kilometers long. He hoped that he could persuade the Solar Survey to do the experiment, which would be quite cheap, and would certainly produce some results of value. The he was going to follow it up with more ambitious schemes, shooting wires out at right angles, and so on..."

  "But I think I've said enough to let you judge for yourselves. There's much more I've not had time to transcribe. I hope you can be patient, at least until after the Centennial. For that, as you are well aware, is what I really came for — and I have work to do..."

  * * * * *

  "Thank you for your moral support, Bob," said Duncan, when he and His Excellency the Ambassador for Titan had emerged into the bright sunlight of Virginia Avenue.

  "I never said a word. I was completely out of my depth. And I kept hoping that someone would put the questi
on I'm still anxious to see answered."

  "What's that?" Duncan asked suspiciously.

  "How did Helmer think he could get away with it?"

  "Oh, that," said Duncan, mildly disappointed; this aspect of the matter seemed so unimportant now. "I think I understand his strategy. Four years ago, when we turned down his project for a simple long-wave detecting system — because we couldn't afford it, and he wouldn't say what he was really driving at — he decided he'd have to go directly to Earth and convince the top scientists there. That meant acquiring funds, somehow. I'm sure he hoped that he'd be vindicated so quickly that we'd forget any minor infractions of the exchange laws. It was a gamble, of course, but he felt it so important that he was prepared to take risks."

  "Hmm," said the Ambassador, obviously not too impressed. "I know that Helmer was a friend of yours, and I don't want to speak harshly of him. But wouldn't it be fair to call him a scientific genius — and a criminal psychopath?"

  Rather to his surprise, Duncan found himself bristling at this description. Yet he had to admit it contained some truth. One of the attributes of the psychopath — a term still popular among laymen, despite three hundred years of professional attempts to eradicate it — was a moral blindness to any interests but his own. Of course, Karl could always produce a very convincing argument that his interests were for the best of all concerned. The Makenzies, Duncan realized with some embarrassment, were also skilled at this kind of exercise.

  "If there were irrational elements in Karl's behavior, they were at least partly due to a breakdown he had fifteen years ago. But that never affected his scientific judgment; everyone I've spoken to agrees that Argus is sound."

  "I don't doubt it — but why is it important? "

  "I'd hoped," said Duncan mildly, "that I'd made that clear to our invisible friends."

  And I believe I have, he told himself, to at least one of them. His most penetrating questioner was certainly one of Terra's top radio astronomers. He would understand, and only a few allies at that level were necessary. Duncan was certain that someday they would meet again, this time eye to eye, and with a pointed lack of reference to any prior encounter.

  "As to why it's important, Bob, I'll tell you something that I didn't mention to the Committee, and which I'm sure Karl never considered, because he was too engrossed in his own affairs. Do you realize what a project like Argus would do to the Titan economy? It would bring us billions and make us the scientific hub of the Solar System. It might even go a long way to solve our financial problems, when the demand for hydrogen starts to drop in the ‘80s."

  "I appreciate that," Farrell answered dryly, "especially as my taxes will go toward it. But let nothing interfere with the March of Science."

  Duncan laughed sympathetically. He like Bob Farrell, and he had been extremely helpful. But he was less and less sure of the Ambassador's loyalties, and it might soon be time to find a replacement. Unfortunately, it would again have to be a Terran, because of this infernal gravity; but that was a problem Titan would always have to live with.

  He could certainly never tell his own ambassador, still less the Argus Committee, why Karl's brainchild might be so vital to the human race. There were speculations in that Minisec — luckily, there was no hint of them in the sketchbook — which had best not be published for many years, until the project had proved itself.

  Karl had been right so often in the past, seizing on truths beyond all bounds of logic and reason, that Duncan felt sure that this last awesome intuition was also correct. Or if it was not, the truth was even stranger; in any event, it was a truth that must be learned. Though the knowledge might be overwhelming, the price of ignorance could be — extinction.

  Here on the streets of this beautiful city, steeped in sunlight and in history, it was hard to take Karl's final comments seriously, as he speculated about the origin of those mysterious waves. And surely even Karl did not really believe all the thoughts he had spoken into the secret memory of his Minisec, during the long voyage to Earth...

  But he was diabolically persuasive, and his arguments had an irresistible logic and momentum of their own. Even if he did not believe all his own conjectures, he might still be right.

  "Item one," he had murmured to himself (it must have been hard to get privacy on that freighter, and Duncan could sometimes hear the noises of the ship, the movements of the other crew members), "these kilohertz waves have a limited range because of interstellar absorption. They would not normally be able to pass from one star to another, unless plasma clouds act as waveguides, channeling them over greater distances. So their origin must be close to the Solar System."

  "My calculations all point to a source — or sources — at about a tenth of a light year from the Sun. Only a fortieth of the way to Alpha Centauri, but two hundred times the distance of Pluto... No man's land — the edge of the wilderness between the stars. But that's exactly where the comets are born, in a great, invisible shell surrounding the Solar System. There's enough material out there for a trillion of those strange objects, orbiting in a cosmic freezer."

  "What's going on, in those huge clouds of hydrogen and helium and all the other elements? There's not much energy — but there may be enough. And where's the matter and energy — and Time — sooner or later there's organization."

  "Call them Star Beasts. Would they be alive? No — that word doesn't apply. Let's just say — ‘Organized systems.’ They'd be hundreds or thousands of kilometers across, and they might live — I mean, maintain their individual identity — for millions of years."

  "That's a thought. The comets that we observe — are they the corpses of Star Beasts, sent sunward for cremation? Or executed criminals? I'm being ridiculously anthropomorphic — but what else can I be?"

  "And are they intelligent? What does that word mean? Are ants intelligent — are the cells of the human body intelligent? Do all the Star Beasts surrounding the Solar System make a single entity — and does It know about us? Or does It care?"

  "Perhaps the Sun keeps them at bay, as in ancient times the campfire kept off the wolves and saber-toothed tigers. But we are already a long way from the Sun, and sooner or later we will meet them. The more we learn, the better."

  "And there's one question I'm almost afraid to think about. Are they gods? OR ARE THEY EATERS OF GODS?

  41

  Independence Day

  Extract from the Congressional Record for 2276 July 4. Address by the Honorable Duncan Makenzie, Special Assistant to the Chief Administrator, Republic of Titan.

  Mr. Speaker, Members of Congress, Distinguished Guests — let me first express my deep gratitude to the Centennial Committee, whose generosity made possible my visit to Earth and to these United States. I bring greetings to all of you from Titan, largest of Saturn's many moons — and the most distant world yet occupied by mankind.

  Five hundred years ago this land was also a frontier — not only geographically but politically. Your ancestors, less than twenty generations in the past, created the first democratic constitution that really worked — and that still works today, on worlds that they could not have imagined in their wildest dreams.

  During these celebrations, many have spoken of the legacy that the founders of the Republic left us on that day, half a thousand years ago. But there have been four Centennials since then; I would like to look briefly at each of them, to see what lessons they have for us.

  At the first, in 1876, the United States was still recovering from a disastrous Civil War. Yet it was also laying the foundation of the technological revolution that would soon transform the Earth. Perhaps it is no coincidence that in the very year of the first Centennial, this country brought forth the invention which really began the conquest of space.

  For in 1876 Alexander Graham Bell made the first practical telephone. We take electronic communications so utterly for granted that we cannot imagine a society without them; we would be deaf and dumb if these extensions of our senses were suddenly removed. So let us
remember that just four hundred years ago, the telephone began the abolition of space — at least upon this planet.

  A century later, in 1976, that process had almost finished — and the conquest of interplanetary space was about to begin. By that time, the first men had already reached the Moon, using techniques which today seem unbelievably primitive. Although all historians now agree that the Apollo Project marked the United States's supreme achievement, and its greatest moment of triumph, it was inspired by political motives that seem ludicrous — indeed, incomprehensible — to our modern minds. And it is no reflection on those first engineers and astronauts that their brilliant pioneering effort was a technological dead end, and that serious space travel did not begin for several decades, with much more advanced vehicles and propulsion systems.

  A century later, in 2076, all the tools needed to open up the planets were ready to hand. Long-duration life-support systems had been perfected; after the initial disasters, the fusion drive had been tamed. But humanity was exhausted by the effort of global rebuilding following the Time of Troubles, and in the aftermath of the Population Crash there was little enthusiasm for the colonization of new worlds.

  Despite these problems, mankind set its feet irrevocably on the road to the stars. During the twenty-first century, the Lunar Base became self-supporting, the Mars Colony was established, and we had secured a bridgehead on Mercury. Venus and the Gas Giants defied us — as indeed they still do — but we had visited all the larger moons and asteroids of the Solar System.

  By 2176, just a hundred years ago, a substantial fraction of the human race was no longer Earthborn. For the first time we had the assurance that whatever happened to the mother world, our cultural heritage would not be lost. It was secure until the death of the Sun — and perhaps beyond...

  The century that lies behind us has been one of consolidation, rather than of fresh discovery. I am proud that my world has played a major role in this process, for without the easily accessible hydrogen of the Titanian atmosphere, travel between the planets would still be exorbitantly expensive.