per second. For the first time, the stars were within man's grasp.

The trip was slow. Even at such fantastic velocities as the Lexman Spacedrive allowed, it took nine years for a ship to reach even the nearest of stars, stop, and return; a distant star such as Bellatrix required a journey lasting two hundred fifteen years each way. But even this was an improvement over the relatively crude spacedrives then in use, which made a journey from Earth to Pluto last for many months and one to the stars almost unthinkable.

The Lexman Spacedrive worked many changes. It gave man the stars. It brought strange creatures to Earth, strange products, strange languages.

But one necessary factor was involved in slower-than-light interstellar travel, one which the Cavour drive would have averted: the Fitzgerald Contraction. Time aboard the great starships that lanced through the void was contracted; the nine-year trip to Alpha Centauri and back seemed to last only six weeks to the men on the ship, thanks to the strange mathematical effects of interstellar travel at high—but not infinite—speeds.

The results were curious, and in some cases tragic. A crew that had aged only six weeks would return to find that Earth had grown nine years older. Customs had changed; new slang words made language unintelligible.

The inevitable development was the rise of a guild of Spacers, men who spent their lives flashing between the suns of the universe and who had little or nothing to do with the planet-bound Earthers left behind. Spacer and Earther, held apart forever by the inexorable mathematics of the Fitzgerald Contraction, came to regard each other with a bitter sort of distaste.

The centuries passed—and the changes worked by the coming of the Lexman Spacedrive became more pronounced. Only a faster-than-light spacedrive could break down the ever-widening gulf between Earther and Spacer—and the faster-than-light drive remained as unattainable a dream as it had been in the days of James Hudson Cavour.

—Sociocultural Dynamics
Leonid Hallman
London, 3876

Chapter
One

The sound of the morning alarm rang out, four loud hard clear gong-clangs, and all over the great starship Valhalla the men of the Crew rolled out of their bunks to begin another day. The great ship had travelled silently through the endless night of space while they slept, bringing them closer and closer to the mother world, Earth. The Valhalla was on the return leg of a journey to Alpha Centauri.

But one man aboard the starship had not waited for the morning alarm. For Alan Donnell the day had begun several hours before. Restless, unable to sleep, he had quietly slipped from his cabin in the fore section, where the unmarried Crewmen lived, and had headed forward to the main viewscreen, in order to stare at the green planet growing steadily larger just ahead.

He stood with his arms folded, a tall red-headed figure, long-legged, a little on the thin side. Today was his seventeenth birthday.

Alan adjusted the fine controls on the viewscreen and brought Earth into sharper focus. He tried to pick out the continents on the planet below, struggling to remember his old history lessons. Tutor Henrich would not be proud of him, he thought.

That's South America down there, he decided, after rejecting the notion that it might be Africa. They had pretty much the same shape, and it was so hard to remember what Earth's continents looked like when there were so many other worlds. But that's South America. And so that's North America just above it. The place where I was born.

Then the 0800 alarm went off, the four commanding gongs that Alan always heard as It's! Time! Wake! Up! The starship began to stir into life. As Alan drew out his Tally and prepared to click off the start of a new day, he felt a strong hand firmly grasp his shoulder.

"Morning, son."

Alan turned from the viewscreen. He saw the tall, gaunt figure of his father standing behind him. His father—and the Valhalla's captain.

"Good rising, Captain."

Captain Donnell eyed him curiously. "You've been up a while, Alan. I can tell. Is there something wrong?"

"Just not sleepy, that's all," Alan said.

"You look troubled about something."

"No, Dad—I'm not," he lied. To cover his confusion he turned his attention to the little plastic gadget he held in his hand—the Tally. He punched the stud; the register whirred and came to life.

He watched as the reading changed. The black-on-yellow dials slid forward from Year 16 Day 365 to Year 17 Day 1.

As the numbers dropped into place his father said, "It's your birthday, is it? Let it be a happy one!"

"Thanks, Dad. You know, it'll feel fine to have a birthday on Earth!"

The Captain nodded. "It's always good to come home, even if we'll have to leave again soon. And this will be the first time you've celebrated your birthday on your native world in—three hundred years, Alan."

Grinning, Alan thought, Three hundred? No, not really. Out loud he said, "You know that's not right, Dad. Not three hundred years. Just seventeen." He looked out at the slowly-spinning green globe of Earth.

"When on Earth, do as the Earthers do," the Captain said. "That's an old proverb of that planet out there. The main vault of the computer files says you were born in 3576, unless I forget. And if you ask any Earther what year this is he'll tell you it's 3876. 3576-3876—that's three hundred years, no?" His eyes twinkled.

"Stop playing games with me, Dad." Alan held forth his Tally. "It doesn't matter what the computer files say. Right here it says Year 17 Day 1, and that's what I'm going by. Who cares what year it is on Earth? This is my world!"

"I know, Alan."

Together they moved away from the viewscreen; it was time for breakfast, and the second gongs were sounding. "I'm just teasing, son. But that's the sort of thing you'll be up against if you leave the Starmen's Enclave—the way your brother did."

Alan frowned and his stomach went cold. He wished the unpleasant topic of his brother had not come up. "You think there's any chance Steve will come back, this time down? Will we be in port long enough for him to find us?"

Captain Donnell's face clouded. "We're going to be on Earth for almost a week," he said in a suddenly harsh voice. "That's ample time for Steve to rejoin us, if he cares to. But I don't imagine he'll care to. And I don't know if I want very much to have him back."

He paused outside the handsomely-panelled door of his private cabin, one hand on the thumb-plate that controlled entrance. His lips were set in a tight thin line. "And remember this, Alan," he said. "Steve's not your twin brother any more. You're only seventeen, and he's almost twenty-six. He'll never be your twin again."

With sudden warmth the captain squeezed his son's arm. "Well, better get up there to eat, Alan. This is going to be a busy day for all of us."

He turned and went into the cabin.

Alan moved along the wide corridor of the great ship toward the mess hall in Section C, thinking about his brother. It had been only about six weeks before, when the Valhalla had made its last previous stop on Earth, that Steve had decided to jump ship.

The Valhalla's schedule had called for them to spend two days on Earth and then leave for Alpha Centauri with a load of colonists for Alpha C IV. A starship's time is always scheduled far in advance, with bookings planned sometimes for decades Earthtime by the Galactic Trade