The comet’s nucieus is bathed in light. The tail and coma trap sunlight throughout a tremendous volume and reflect it, some to Earth, some to space, some to the nucleus itself.

The comet has suffered. Explosions in the head have torn it into mountainous chunks. Megatons of volatile chemicals have boiled away. The large masses in the head are crusted with icy mud from which most of the water ice has boiled away.

Yet the crusts retard further evaporation. Other comets have survived many such passages through the maelstrom. Much mass has been lost, poured into the tail; but much of the coma could freeze again, and the rocky chunks could merge; and crystals of strange ices could plate themselves across a growing comet, out there in the dark and the cold, over the millions of years ... if only Hamner-Brown could return to the cometary halo.

But there appears to be something in its path.

LUCIFER’S HAMMER, 1977

From WORLD OF PTAVVS

This was my first novella and my first novel. The first few thousand words were written in longhand during a trip through Europe. I took my time over it. When I thought it was ready I sent the novella to Fred Pohl, who had already bought two stories from me.

Fred chose the title. My choice was “A Relic of Empire.” I liked it well enough to recycle, hanging it on a short story. Jack Gaughan sketched various of the alien life-forms in “Ptavvs,” and I first felt the terrific ego-kick of seeing something from my own mind rendered visible.

Fred used the novella to get the attention of Belly Ballantine at Ballantine Books. On the strength of that Belly sent me a contract for a novel. I would not have thought of that. I was a poor businessperson in those days, but I recognized an opportunity when Fred hit me in the face with it.

WORLD OF PTAVVS established some patterns that have persisted throughout my career, more or less. Optimism. Logic problems. Bizarre technology derived from esoteric physics. Aliens with depth to them. (Algis Budrys, writing as a critic, said that telepathy in most current novels felt like something from Ma Bell; that in PTAVVS, it didn’t.) In particular, I taught myself to enjoy playing games with astrophysics.

I played such games throughout PTAWS and many that followed. The excerpt is from near The end, as Kzanol and Larry Greenberg (carrying Kzanol’s memories) are about to land a fusion spacecraft on Pluto. I would hate today to defend the thesis that the planet Pluto can catch fire, but it made some great scenes.

Kzanol/Greenberg swallowed, swallowed again. The low acceleration bothered him. He blamed it on his human body. He sat in a window seat with the crash web tightly fastened, looking out and down.

There was little to see. The ship had circled half the world, falling ever lower, but the only feature on an unchanging cue-ball surface had been the slow creep of the planetary shadow. Now the ship flew over the night side, and the only light was the dim light of the drive, dim at least when reflected from this height. And there was nothing to see at all.

Until now.

Something was rising on the eastern horizon, something a shade lighter than the black plain. An irregular line against the stars. Kzanol/Greenberg leaned forward as he began to realize just how big the range was, for it couldn’t be anything but a mountain range. “What’s that?” he wondered aloud.

“One hundredth diltun.” Kzanol probed the pilot’s mind. The pilot said, “Cott’s Crescent. Frozen hydrogen piled up along the dawn side of the planet. As it rotates into daylight the hydrogen boils off and then refreezes on the night side. Eventually it rotates back to here.”

“Oh. Thanks.”

Evanescent mountains of hydrogen snow, smooth and low, like a tray of differently sized snowballs dropped from a height. They rose gently before the slowing ship, rank behind rank, showing the tremendous breadth of the range. But they couldn’t show its length. Kzanol/Greenberg could see only that the mountains stretched half around the horizon; but he could imagine them marching from pole to pole around the curve of the world. As they must. As they did.

The ship was almost down, hovering motionless a few miles west of the beginning rise of the Crescent. A pillar of fire licked a mile down to touch the surface. Where it touched, the surface disappeared. A channel like the bed of a river followed below the ship, fading into the darkness beyond the reach of the light.

The ship rode with nose tilted high; the fusion flame reached slightly forward. Gently, gently, one mile up, the Golden Circle slowed and stopped.

Where the flame touched, the surface disappeared. A wide, shallow crater formed below the descending ship. It deepened rapidly. A ring of fog formed, soft and white and opaque, thickening in the cold and the dark, closing in on the ship. Then there was nothing but the lighted fog and the crater and the licking fusion fire.

This was the most alien place. He had been wasting his life searching out the inhabited worlds of the galaxy; for never had they given him such

a flavor of strangehess as came from this icy world, colder than. . . than the bottom of Dante’s Hell.

“We’ll be landing on the water ice layer,” the pilot explained, just as if he’d been asked. He had. “The gas layers wouldn’t hold us. But first we have to dig down.”

Had he been searching for strangeness? Wasn’t that a Greenberg thought slipping into his conscious mind? Yes. This soul-satisfaction was the old Greenberg starlust; he had searched for wealth, only wealth.

The crater looked like an open pit mine now, with a sloping ring wall and then an almost flat rim and then another, deeper ring wall and

Kzanol/Greenberg looked down, grinning and squinting against the glare, trying to guess which layer was which gas. They had been drilling through a very thick blanket of ice, hundreds or thousands of feet thick. Perhaps it was nitrogen? Then the next layer, appearing now, would be oxygen. The plain and the space above it exploded in flame.

“She blows!” Lew crowed, like a felon reprieved. A towering, twisting pillar of yellow and blue flame roared straight up out of the telescope, out of the pale plain where there had been the small white star of the Golden Circle. For a moment the star shone brightly through the flames. Then it was swamped, and the whole scope was fire. Lew dropped the magnification by a ten-factor to watch the fire spread. Then he had to drop it again. And again.

Pluto was on fire. For billions of years a thick blanket of relatively inert nitrogen ice had protected the highly reactive layers below. Meteors, as scarce out here as sperm whales in a goldfish bowl, inevitably buried themselves in the nitrogen layer. There had been no combustion on Pluto since Kzanol’s spaceship smashed down from the stars. But now hydrogen vapor mixed with oxygen vapor, and they burned. Other elements burned too.

The fire spread outward in a circle. A strong, hot wind blew out and up into vacuum, fanning great sheets of flame over the boiling ices until raw oxygen was exposed. Then the fire dug deeper. There were raw metals below the thin sheet of water ice; and it was thin, nonexistent in places, for it had all formed when the spaceship struck, untold eons ago, when food yeast still ruled Earth. Sodium and calcium veins; even iron bums furiously in the presence of enough oxygen and enough heat. Or chlorine, or fluorine; both halogens were present, blowing off the top of Pluto’s frozen atmosphere, some burning with hydrogen in the first sheets of flame. Raise the temperature enough and even oxygen and nitrogen will unite.

Lew watched his screen in single-minded concentration. He thought of his future great-great-grandchildren and wondered how he could possibly make them see this as he saw it now. Old and leathery and hairless

and sedentary, he would tell those children: “I saw a world burning when I was young. . . .“ He would never see anything as strange.

Pluto was a black disc almost covering his scope screen, with a cold highlight near the sunward arm. In that disc the broad ring of fire had almost become a great circle, with one arc crawling over the edge of the world. When it contracted on the other side of the world there would be an explosion such as could only be imagined. But in the center the ring was darkening to black, its fuel nearly burned out.

The coldest spot within the ring was the point where the fire had started.

The fire had slowed now. Most of the unburned hydrogen had been blown before the fire, until it was congested into a cloud mass opposite on Pluto from the resting place of the Golden Circle. Around that cloud bank raged a hurricane of awesome proportions. Frozen rain poured out of the heavens in huge lens-shaped drops, hissing into the nitrogen snow. The layers above nitrogen were gone, vaporized, gas diluting the hydrogen which still poured in. On the borderline hydrogen burned fitfully with halogens, and even with nitrogen to form ammonia, but around most of the great circle the fires had gone out. Relatively small, isolated conflagrations ate their way toward the new center. The “hot” water ice continued to fall. When it had boiled the nitrogen away it would begin on the oxygen. And then there would be a fire.

At the center of the hurricane the ice stood like a tremendous Arizona butte. Even the halogens were still frozen across its flat top, thousands of square miles of fiourine ice with near-vacuum above. Coriolis effects held back the burning wind for a time.

Alexel Panshin wrote a savage revIew of PTAVVS. I wish I had a copy, but I tore the fanzlne up in a rage, and I don’t remember the name or even the editor, I was fool enough to write an answer to that review! I learned better later Meanwhile Alexel had used PTAWS In an essay on writing, as a textbook case of how not to write science fiction.

The editor, Ghod bless him, persuaded both of us to bury our respective submissions.

My memory says that that Issue Included Panshln’s reviews of a dozen books. He considered them all failures, even Heinlein’s THE MOON IS A HARSH MISTRESS, with but a single exception, Ted White’s THE SECRET OF THE MARAUDER SATELLITE entirely lived up to Panshin’s standards.