Donald Moffitt - Genesis 02

replaced the first crude boron fusion-fission starships of the Nar’s early space age, and could travel at up to one-seventh of the speed of light. With them, the Nar could spread slowly from star to star and hope to populate the galaxy in a million years or two.
    But only recently a conceptual breakthrough had raised the possibility of a relativistic spacecraft that could reach the core of the galaxy in only fifty thousand years. With it, the Nar could do on a smaller scale what Original Man had done so grandly—use it as a robot beacon to broadcast their own genetic code to the billions of stars that would come within its range. If the probe hit the jackpot only once or twice, then the Nar race could spread from new foci, sending brothers among the stars who would be waiting to greet them.
    To this lofty purpose, the Nar species had allocated a tremendous share of the wealth of their civilization. The robot spacecraft project had been given a timetable that might make it a reality in only a few centuries—a fraction of a Nar lifetime.
    Now, in an act of stunning generosity, the Nar decided to speed up the timetable—and bequeath the relativistic engine to the human race. With it, those humans who wished to—the restless ones, the unhappy ones, the adventurous ones—could return to their mythical home in another galaxy. The trip would take thirty-seven million years of real time, of course, but it had been calculated that by traveling within one hundred millionth of one percent of the speed of light, the time dilation factor predicted by the theory of relativity would have a value of approximately seventy thousand. So to the travelers, the journey would seem to last only about five hundred and forty years.
    And when you had eternity to play with, that didn’t seem like too high a price to pay.
    To reach that tremendous terminal velocity—to become pregnant with enough kinetic energy to coast between the galaxies in a fuel-less void—the ramjet craft would first have to dive to the heart of the departure galaxy, gulping the rich H-II clouds as it went, then let the gravitational center of the galaxy sling it above the plane and out into emptiness.
    So it all worked out to everybody’s benefit. The humans would be able to do the Nar’s little chore for them on the way home.
    One problem remained. Robot ramjets were not very hospitable to life. They were hot ! And even if a way were found around that problem, there was still the question of living space and a reliable supportive environment for a substantial fraction of the human race on a trip that would last for more than five hundred years.
    How would it be managed?
    It was simple. The spacecraft would tow a tree.
     
    Mim appeared in a stunning green off-the-shoulder party dress with a five-pointed hem that, though it was a bit old-fashioned compared to some of the newer styles, suited her very well. Over it she wore a short pleated chlamys that left her right arm bare—an old cellist’s habit.
    She bent over the chairpuff and kissed Bram lightly above one eyebrow. “What are you sitting here brooding about?” she said.
    “Oh, I was just thinking about the Father World,” Bram said, getting up. “It seems very far away now.”
    “It is far away! Tens of thousands of light-years away!”
    “Which means that tens of thousand of years have passed since we left. We’re in their historical past, Mim. After only a couple of decades of travel. I wonder if they’ve forgotten us.”
    “Not a chance. The Nar never forget anything.”
    “All the Nar we knew are dead now. But there ought to be some fifty-thousand-year-old humans that we used to know walking around. I wonder what it’s like to be fifty thousand years old. We’re still under a hundred.”
    “And getting younger every day,” she reminded him.
    “Yes. I wonder if fifty thousand years is long enough for a human being to learn the Great Language. Jao swears that it’s possible, with cortical transplants, electronic interfacing, and prosthetic touch sleeves.”
    “It must be a very different society from the one we grew up in,” she commented.
    “We’ll never know,” he said. “The people who stayed behind made their choice and we made ours. Speaking of which …”
    He inclined an ear to the noise in the outside corridor. Some drunk was singing a Bobbing Day carol—off key— and his friends were making it worse by attempting harmony. Mim winced.
    “Yes, we’re developing our