PERIL ORBIT

Across the blazing face of the sun moved a round dark speck, a tiny, one-man space ship. It was very small, very close, and utterly helpless. The side facing the sun glowed dull red.

Inside, Jim MacDonald stood glumly regarding the thermometer on the pilot compartment bulkhead. Sweat made dark patches on the light blue of his uniform and ran in beads down his forehead. He rubbed his arm across his face. The thermometer read over two hundred. He shook his head slowly. It couldn't be that hot, heat must be conducting along the magnesium bulkhead to the instrument.

Jim ran his fingers through his hair to brush back the damp strands that clung to his forehead. The hand came away with little droplets clinging to his fingertips. He wiped it across his pants, and tapped the thermometer again. The pointer stayed where it was, stuck against the peg.

"About one forty-five," he guessed aloud, and turned to walk with a slow, dragging step across to the pilot's seat. Weakly he slumped down with his arms dangling loose over the chair arms, knuckles almost touching the deck. He sat very still trying to ignore the temperature in the compartment, but the hot stifle wrapped around him and his chest heaved in a sigh.

Jim MacDonald was done for and he knew it. The thermo-couple to the outside skin showed three thousand degrees. The inside cooling system had not been built for this and had long since ceased to cope with the heat. There seemed to be no use continuing his grim little existence, or facing the worse smother of heat to come.

Yet, driven by the dull automatism of training and habit, he listlessly swung the stand with the ship's log over before him and noted his temperature readings. Then he critically reread what he had already written.

A few days ago, he had been using the gravitational field of the sun as a booster to help fling the little ship from Earth to Venus. In the mighty field, a space warp had funneled out, caught him, and sucked the ship toward the blazing maw.

The struggle to escape was a masterpiece of calculation. He had figured with such a nicety that his fuel had run out just at the moment the jet tubes at the rear became molten lumps on the ship's skin. He had escaped the warp. But it was a futile thing now, for the ship swung around the sun fuelless, inoperative, in a tight orbit that had a little initial inward momentum.

He had tried to radio for help, but radioing from where he was, was like trying to signal from the heart of an atomic bomb; if a signal got through, it would be only a part of the meaningless jabber of static that always came from here. And if the little black speck were seen, it would only be taken for a stray meteorite moving across the sun's incandescent face.

The ship was a little spherical world. It turned on its own axis once in an hour and twenty minutes. That was its little day. The orbit spiralled now a mere quarter million miles from the sun, one little year to two earth days. It moved closer at a rate that accelerated a few feet per second every second.

Eventually, said the impassive rows of equations in the log, the inward movement would stop, as keeping the same speed in a smaller circle, the ship's centrifugal force increased to set up an equilibrium. But that point would be three thousand miles below the sun's surface. The ship would never reach it. Jim MacDonald inhabited a doomed little world.

He chuckled. He even had a moon. The natural physical function of a few minutes before had left a jagged little chunk of ice swinging around the ship, outside the waste lock on the side away from the sun. But that wouldn't last long. It would pass into the hot light, and vanish in a puff of steam.

Now the plastic fittings of the compartment began to send up a nostril stinging stench. Jim leafed over a few pages in the log to the page printed at the top: ... Suggestions for redesign of space-ships.

Under his note, Enlarge cooling systems, he wrote, Replace urea formaldehyde plastics with metals, and insulate compartment thermometers from bulkheads.

Feeling foolish at the useless act of writing that which no one would ever read, Jim swung the log away. His tongue peeled from the roof of his mouth like a strip of adhesive tape and he dragged across the compartment for a drink. Glancing toward the sun, he held his aluminum cup under the spout and pressed the hot button gingerly. Although the windows on that side were blanked out almost purple, the sun's horizon glared through in a heaving mass of leaping gassy prominences.

Jim turned away, his face wrinkling into a grimace. Across the compartment a little cabinet held a pistol. It would be a simple sane thing to walk across there, take out the pistol and bring this to a sudden stop. He stepped toward it, then turned away ashamed. Spacemen didn't think like that.

Ahead of the ship something flared into incandescent brilliance. Waves of force pounded on the front, the deck heaved. Jim sprawled on his face and skidded over under the instrument panel, his cup clattering along beside him.

The deck scorched his hands and face. He wriggled out and dragged himself up to the chair, clinging tightly. But it was all over. He stood for a moment, waiting, then sat down.

Experimentally he caressed his burned face. Looking out the windows he tried to see some cause for the shock. Then he realized his moon was gone. It had passed out of the deep shadow into the penumbra of the ship and had been instantly vaporized. The shock had been its dissociated molecules pummeling the front of the ship.

He would have to be careful. If that could have passed directly into the full light instead of through the half shadow of the penumbra, the front of the ship might have caved in, softened as it was to near plasticity. Jim reached for the log again, but his hand stopped in mid air. With the spaceman's sensitivity to changes of state, he knew something was wrong. Something had changed in the shock of the moon's explosion.

He puzzled it over, but his heat befuddled brain refused to grasp things. He scanned all the instruments on the panel, but saw nothing unusual. At one side, he had a little tracer going, little drum turning with a needle scribing a red line. On it he had set the increase in the sun's pull against time to describe a curve. He examined this curve. The red line had changed direction suddenly; the sun's pull was increasing faster.

"Dammit!" he said. The force of the explosion in front had slowed him and shorn off some protective centrifugal force. Now he picked up points on the new curve, set down equations, and found he would die some twenty hours sooner than he had expected.

His mind began to revolt at the training that made him go on like this. The turning of the ship now showed him only the face of the sun. He looked at it a while, then shrugged his shoulders in disgust. Slowly he got up and walked toward the gun cabinet. The little door swung open as he pressed the button and he stared at the holstered weapon.

Leaving the door open, he walked away, looking back toward it. He retrieved his cup and filled it with tepid water. Throwing his head back he drained it at a gulp; then refilled it. He walked to the engine compartment door. It swung open at his touch, and he stepped into the tiny gangway. Here a tiny porthole looked out into the infinite blue-black deeps of space. Jim leaned against a bulkhead and wiped sweat from his eyes.

He tried to think. Not of escape, but of the frigid emptiness of space, the cool earth he had left behind. Into his mind came a fleeting glimpse of a lake back home on earth, a cold lake ringed with blue-green pines, jade waters where he had dived deep with the iciness stinging his skin. Against the metal bulkhead, his back began to burn. The vision faded. He realized he was thirsty all over.

He gulped his cup of water and went back to the pilot's compartment. At the open door of the gun cabinet, he stopped and sent his empty cup clattering against the sunward windows. He took the gun from the cabinet.

Back to the pilot's chair again. He toyed with the gun. The ship had turned now so that the other vast heaving horizon cut across the view. "Oh, hell!" Jim said, and brought the gun's muzzle to his mouth.

"Oh, hell!" Jim said and brought the gun's muzzle to his mouth.

Then he lowered it, sweat poured down into his eyes as his forehead wrinkled in dull puzzlement. He should be thinking about something, he was forgetting something. Jim tried to cudgel his heat-beclouded brain into some semblance of order.... Water, explosion, change of velocity.... Where was the drain outlet for the water supply located?

He laid the gun aside and riffled through a drawer of blueprints, until he found the piping layout. Now he explored the maze of piping along the ship's sunward side. There it was, a little brass valve with a pipe leading to the outside skin.

The valve was hot enough to sear his hand. Jim carefully wrapped his handkerchief around the handle and twisted gently. Inside pressure squirted a thin stream of water from the supply tank into the hot vacuum of space. As it vaporized and dissociated into its atoms, Jim felt a mighty surge of expansion against the ship. The blows of a soft fist pummeled the side.

Jim groaned as the softened plates of the hull creaked and buckled, but he held the valve as it was. An inside panel split and let a thin sifting of insulation drift to the deck. His knee was against the deck plates and he became conscious of the burning through the cloth of his uniform. But he stayed there, until through the windows he saw nothing but the speckled black of space turn slowly up. Then he shut the valve off and, rubbing his burned knee, anxiously hobbled to the tracer.

The red line had not so much swoop to it now. "Ya!" he shouted exultantly. The centrifugal force from his forward velocity needed just a little help to begin pushing him away from the sun. Jim read the water tank gauge; about twenty gallons left.

Fidgeting, he waited another hour. The sun's horizon swung up into view, the blazing plain filled the windows and at last he saw again the other horizon. It would not do to twist the valve too soon; he had to wait until the outlet was directly toward the sun so he wouldn't lose any precious forward velocity.

The sun's horizon bisected the windows. Now! Encouraged by his other success, Jim twisted the valve hard. He stepped back so his sore knee would not rest against the plates.

The ship bounced like a beachball in the tremendous upshoot of the gases outside. Jim clung to a stanchion to keep from being knocked off his feet.

Like a rubber ball dimpled by a thumb, the ship's skin began to bulge inward. Jim tried to let go his hold to get the valve.

The bounce of the ship knocked him to his knees. A little steel desk came sliding across the compartment, banging him on the shoulder. He let go with one hand and shoved the desk between the bulging wall and a cross bulkhead. A white line appeared across the desk, and the paint crackled as it began to fold in the middle.

Jim let go and dived for the valve. A panel split wide and insulation poured out. A scream bubbled from his throat as radiation cut a line across his face.

He rolled away, then struggled to get to the valve again. But the push stopped. The tank was empty.

Groaning with the pain of his face, Jim went to his tracer. He forgot the burn as he saw the curve now paralleled zero. No ... it went up a little. Jim whooped for joy.

Now he scurried about the ship gathering together all the liquids he could find. Soup, fruit juice, medicines. He piled them beside the water tank and unscrewed the cap. Air whooshed in.

At the sound, Jim grinned. He left his pile of cans and bottles as they were, and unscrewed the cap to a spare oxygen tank. The compartment air pressure went up to about twenty five pounds. The excess of oxygen exhilarated him.

He looked over his pile of cans and bottles. He didn't like consomme, it went into the tank. Chicken broth followed. Everything he didn't like went into the tank, everything else stayed out. Then he patched the rip in the panel.

It was time. Jim crouched carefully beside the valve, opening it slowly. The mess inside the tank squirted out. Again the surge beat against the ship, but with the first groan of the hull, Jim throttled the valve down a little. His eyes were on the compartment pressure gauge. The consomme went and inside air began to hiss out. As it too expanded, the push on the hull continued.

When the sun's horizon was out of sight, the inside pressure registered only twelve pounds. Jim shut the valve off.

Now the tracer line was a nice curve upward.

Jim swung into the pilot's chair. He was a little oxygen drunk, but he made calculations grow on the page until he had his result. Then he leaned back and gave the universe a beatific smile.

His spiral now outward, would stop as soon as his orbit expanded and centrifugal force became less. As the forces came into balance, he would take up a permanent orbit around the sun. But that orbit lay well outside the region of heavy static, and he could radio for help. In his mind he already heard the sweet clang of magnetic grapples against the hull.

Jim reached for the log and began to letter neatly at the top of a new page:

Suggestions for spacemen caught in the sun.