Space Tug Part 10

It exploded with a blast of pure brightness like that of the sun.

The Platform went on its monotonous round about the planet from which it had risen only weeks before. Sanford was strapped in a bunk and fed through a tube, and on occasion ma.s.saged and variously tended to keep him alive. The men on the Platform worked. They made telephoto maps of Earth. They took highly magnified, long-exposure photographs of Mars, pictures that could not possibly be made with such distinctness from the bottom of Earth's turbulent ocean of air.

There was a great deal of official business to be done. Weather observations of the form and distribution of cloud ma.s.ses were an important matter. The Platform could make much more precise measurements of the solar constant than could be obtained below. The flickering radar was gathering information for studies of the frequency and size of meteoric particles outside the atmosphere. There was the extremely important project for securing and sealing in really good vacua in various electronic devices brought up by Joe and his crew in the supply ship.

But sometimes Joe managed to talk to Sally.

It was very satisfying to see her on the television screen in personal conversation. Their talk couldn't be exactly private, because it could be picked up elsewhere. It probably was. But she told Joe how she felt, and she wanted to read him the newspaper stories based on the reports Brent had sent down. Brent was in command of the Platform now that Sanford lay in a resolute coma in his bunk. But Joe discouraged such waste of time.

"How's the food?" asked Sally. "Are you people getting any fresh vegetables from the hydroponic garden?"

They were, and Joe told her so. The huge chamber in which sun-lamps glowed for a measured number of hours in each twenty-four produced incredibly luxuriant vegetation. It kept the air of the ship breathable.

It even changed the smell of it from time to time, so that there was no feeling of staleness.

"And the cooking system's really good?" she wanted to know. Sally was partly responsible for that, too. "And how about the bunks?"

"I sleep now," Joe admitted.

That had been difficult. It was possible to get used to weightlessness while awake. One would slip, sometimes, and find himself suddenly tense and panicky because he'd abruptly noticed all over again that he was falling. But--and yet again Sally was partly responsible--the bunks were designed to help in that difficulty. Each bunk had an inflatable top blanket. One crawled in and settled down, and turned the petc.o.c.k that inflated the cover. Then it held one quite gently but rea.s.suringly in place. It was possible to stir and to turn over, but the feeling of being held fast was very comforting. With a little care about what one thought of before going to sleep, one could get a refreshing eight hours' rest. The bunks were luxury.

Sally said: "The date and time's a secret, of course, because it might be overheard, but there'll be another ship up before too long. It's bringing landing rockets for you to come back with."

"That's good!" said Joe. It would feel good to set foot on solid ground again. He looked at Sally and said eagerly, "We've got a date the evening I get back?"

"We've got a date," she said, nodding.

But it couldn't very well be a definite date. There were people with ideas that ran counter to plans for Joe to get back to Earth and a date with Sally Holt. The s.p.a.ce Platform was not admired uniformly by all the nations of Earth. The United States had built it because the United Nations couldn't, and one of the attractions of the idea had been that once it got out to s.p.a.ce and was armed, peace must reign upon Earth because it could smack down anybody who made war.

The trouble was that it wasn't armed well enough. Six guided missiles couldn't defend it indefinitely. It looked as helpless as isolated Berlin did before the first airlift proved what men and planes could do in the way of transport. And the Platform's enemies didn't intend for it to be saved by a rocketlift. They would try to smash it before such a lift could get started.

A week after Joe got to it with the guided missiles, three rockets attacked. They went up from somewhere in the middle of the Pacific. One blew up 250 miles below the Platform. Another detonated 190 miles away.

For safety's sake the third was crashed--at the cost of one guided missile--when it had come within 50 miles.

The screen of tin cans worked, but it wasn't thick enough. The occupants of the Platform went about hunting for sheet metal that could be spared.

They pulled out minor part.i.tions here and there, and went out on the surface and threw away thousands of small glittering sc.r.a.ps of metal in all directions.

Two weeks later, there was another attack. It could be calculated that Joe couldn't have carried up more than six guided missiles. There might be as few as two of them left. So eight rockets came up together--and the first of them went off 400 miles from the Platform. Only one got as close as 200 miles. No guided missiles were expended in defense.

The Platform's enemies tried once more. This time the rockets arched up above the Platform's...o...b..t and dived on the satellite from above. There were two of them. They went off at 180 and 270 miles from the Platform.

Joe's trash screen would not work on Earth, but in s.p.a.ce it was an adequate defense against anything equipped with proximity fuses. It could be a.s.sumed that in a full-scale s.p.a.ce-war nuts, bolts, rusty nails and beer bottle caps would become essential military equipment.

Three days after this last attack, a second supply ship took off from Earth. Lieutenant Commander Brown was a pa.s.senger. Its start was just like the one Joe's ship had made. Pushpots lifted it, jatos hurled it on, and then the furious, flaming take-off rockets drove it valiantly out toward the stars.

Joe's ship had been moved out of the landing lock and was moored against the Platform's hull. The second ship made contact in two hours and seventeen minutes from take-off. It arrived with its own landing rockets intact, and it brought a set of forty-foot metal tubes for Joe's ship to get back to Earth with. But those landing rockets and Lieutenant Commander Brown const.i.tuted all its payload. It couldn't bring up anything else.

And Lieutenant Commander Brown called a very formal meeting in the huge living s.p.a.ce at the Platform's center. He stood up grandly in full uniform--and had to hook his feet around a chair leg to keep from floating absurdly in mid-air. This detracted slightly from the dignity of his stance, but not from the official voice with which he read two doc.u.ments aloud.

The first paper detached Lieutenant Commander Brown from his regular naval duties and a.s.signed him pro tem to service with the s.p.a.ce Exploration Project. The second was an order directing him to take command and a.s.sume direction of the s.p.a.ce Platform.

Having read his orders, he cleared his throat and said cordially, "I am honored to serve here with you. Frankly, I expect to learn much from you and to have very few orders to give. I expect merely to exercise such authority as experience at sea has taught me is necessary for a tight and happy ship. I trust this will be one."

He beamed. n.o.body was impressed. It was perfectly obvious that he'd simply been sent up to acquire experience in s.p.a.ce for later naval use, and that he'd been placed in command because it was unthinkable that he serve under anyone without official rank and authority. And he quite honestly believed that his coming, with experience in command, was a blessing to the Platform. In fact, there was no danger that this commander of the Platform would crack up under stress as Sanford had.

But it was too bad that he hadn't brought some long-range guided missiles with him.

Joe's ship had brought up twenty tons of cargo and twenty tons of landing rockets. The second ship brought up twenty tons of landing rockets for Joe, and twenty tons of landing rockets for itself. That was all. The second trip out to the s.p.a.ce Platform was a rescue mission and nothing else. Arithmetic wouldn't let it be anything else. And there couldn't be any idea of n.o.ble self-sacrifice and staying out at the Platform, either, because only four ships like Joe's had been begun, and only two were even near completion. Joe's had taken off the instant it was finished. The second had done the same. The second pair of s.p.a.ceships wouldn't be ready for two months or more. The ships that could be used had to be used.

So, only thirty-six hours after the arrival of the second rocketship at the Platform, the two of them took off together to return to Earth.

Joe's ship left the airlock first. Sanford was loaded in the cabin of the other ship as cargo. Lieutenant Commander Brown stayed out at the Platform to replace him.

Obviously, in order to get back to Earth they headed away from it in fleet formation. They pointed their rounded noses toward the Milky Way.

The upward course was an application of the principle that made the screen of tin cans and oddments remain about the Platform. Each of those small objects had had the Platform's own velocity and orbit.

Thrown away from it, the centers of their orbits changed. In theory, the center of the Platform's...o...b..t was the center of Earth. But the centers of the orbits of the thrown-away objects were pushed a few miles--twenty--fifty--a hundred--away from the center of Earth.

The returning s.p.a.ce ships also had the orbit and speed of the Platform.

They wanted to shift the centers of their orbits by very nearly 4,000 miles, so that at one point they would just barely graze Earth's atmosphere, lose some speed to it, and then bounce out to empty s.p.a.ce again before they melted. Cooled off, they'd make another grazing bounce. After eight such bounces they'd stay in the air, and the stubby fins would give them a sort of gliding angle and controllability, while the landing rockets would let them down to solid ground. Or so it was hoped.

Meanwhile they headed out instead of in toward Earth. They went out on their steering-rockets only, using the liquid fuel that had not been needed for course correction on the way out. At 4,000 miles up, the force of gravity is just one-fourth of that at the Earth's surface. It still exists; it is merely canceled out in an orbit. The ships could move outward at less cost in fuel than they could move in.

So they went out and out on parallel courses, and the Platform dwindled behind them. Night flowed below until the hull of the artificial satellite shone brightly against a background of seeming sheer nothingness.

The twilight zone of Earth's shadow reached the Platform. It glowed redly, glowed crimson, glowed the deepest possible color that could be seen, and winked out. The ships climbed on, using their tiny steering rockets.

Nothing happened. The ships drew away from each other for safety. They were 50, then 60 miles apart. One glowed red and vanished in the shadow of the Earth. The other was extinguished in the same way. Then they went hurtling through the blackness of the night side of Earth. Microwaves from the ground played upon them--radar used by friend and foe alike--and the friendly radar guided tight-beam communicator waves to them with comforting a.s.surance that their joint course and height and speed were exactly the calculated optimum. But they could not be seen at all.

When they appeared again they were still farther out from Earth than the Platform's...o...b..t, but no farther from each other. And they were descending. The centers of their orbits had been displaced very, very far indeed.

Going out, naturally, the ships had lost angular speed as they gained in height. Descending, they gained in angular velocity as they lost height. They were not quite 30 miles apart as they sped with increasing, headlong speed and rushed toward the edge of the world's disk. When they were only 2,000 miles high, the Earth's surface under them moved much faster than it had on the way up. When they were only 1,000 miles high, the seas and continents seemed to flow past like a rushing river. At 500 miles, mountains and plains were just distinguishable as they raced past underneath. At 200 miles there was merely a churning, hurtling surface on which one could not focus one's eyes because of the speed of its movement.

They missed the solid surface of Earth by barely 40 miles. They were moving at a completely impossible speed. The energy of their position 4,000 miles high had been transformed into kinetic energy of motion. And at 40 miles there is something very close to a vacuum, compared to sea-level. But compared to true emptiness, and at the speed of meteors, the thin air had a violent effect.

A thin humming sound began. It grew louder. The substance of the ship was responding to the impact of the thin air upon it. The sound rose to a roar, to a bellow, to a thunderous tumult. The ship quivered and trembled. It shook. A violent vibration set up and grew more and more savage. The whole ship shook with a dreadful persistence, each vibration more monstrous, more straining, more ominous than before.

The four in the s.p.a.ce ship cabin knew torture. Weight returned to them, weight more violent than the six gravities they had known for a bare fourteen seconds at take-off. But that, at least, had been smoothly applied. This was deceleration at a higher figure yet, and accompanied by the shaking of bodies which weighed seven times as much as ever before--and bodies, too, which for weeks past had been subject to no weight at all.

They endured. Nothing at all could be done. At so many miles per second no possible human action could be determined upon and attempted in time to have any effect upon the course of the ship. Joe could see out a quartzite port. The ground 40 miles below was merely a blur. There was a black sky overhead, which did not seem to stir. But cloud-ma.s.ses rushed at express-train speed below him, and his body weighed more than half a ton, and the ship made the sound of innumerable thunders and shook, and shook and shook....

And then, when it seemed that it must fly utterly to pieces, the thunder diminished gradually to a bellow, and the bellow to a roar, and the roaring.... And the unthinkable weight oppressing him grew less.

The Earth was farther away and moving farther still. They were 100 miles high. They were 200 miles high....

There was no longer any sound at all, except their gaspings for breath.

Their muscles had refused to lift their chests at all during the most brutal of the deceleration period.

Presently Joe croaked a question. He looked at the hull-temperature indicators. They were very, very high. He found that he was bruised where he had strapped himself in. The places where each strap had held his heavy body against the ship's vibrations were deeply black-and-blue.

The Chief said thickly: "Joe, somehow I don't think this is going to work. When do we hit again?"