Imperial Earth

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 Eke 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

278 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 selfassured—came out of the air behind him.

“But this is all old material, familiar to everyone in the field. Sandema

Duncan felt his facade of instant expertise rapidly crumbling; he should have guessed that there would be someone in his audience who would know far more about this 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 ante

“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. In fact the only 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 ante

telescopes. “You may wonder-as I did-how he ever hoped to get such a gigantic project started. He pla

“He was going to launch two equal, massive weights in exactly opposite directions, each towing a fine wire, several hundred kilometers long. When the wires had been completely deployed, the weights would be jettisoned—and he would have a simple dipole ante

“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 Cente

“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 question I’m stiff anxious to see answered.”

“What’s that?” Duncan asked suspiciously.

“How did Helmer think he could get away with 09)

“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 in281 fraction 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.”