The Burning Bridge | Page 7

involved only men, I guess I could handle the problem. But there are women along, and children."
"And you want a female viewpoint. You're wiser than I had realized. But why me?"
He forced himself to meet her eyes. "You appear the most sensible of the women awake."
"Really!" She laughed. "I appreciate the compliment, but must you deliver it in that parade-ground voice, and glare at me to boot? Relax, captain." She cocked her head, studying him. Then: "Several of the girls don't get this business of the critical point. I tried to explain, but I was only an R.N. at home, and I'm afraid I muddled it rather. Could you put it in words of one and a half syllables?"
"Do you mean the equal-time point?"
"The Point of No Return, some of them call it."
"Nonsense! It's only--Well, look at it this way. We accelerated from Sol at one gravity. We dare not apply more acceleration, even though we could, because so many articles aboard have been lightly built to save mass--the coldvats, for example. They'd collapse under their own weight, and the persons within would die, if we went as much as one-point-five gee. Very well. It took us about one hundred eighty days to reach maximum velocity. In the course of that period, we covered not quite one-and-a-half light-months. We will now go free for almost forty years. At the end of that time, we'll decelerate at one gee for some one hundred eighty days, covering an additional light-month and a half, and enter the e Eridani System with low relative speed. Our star-to-star orbit was plotted with care, but of course the errors add up to many Astronomical Units; furthermore, we have to maneuver, put our ships in orbit about Rustum, send ferry craft back and forth. So we carry a reaction-mass reserve which allows us a total velocity change of about one thousand kilometers per second after journey's end.
"Now imagine we had changed our minds immediately after reaching full speed. We'd still have to decelerate in order to return. So we'd be almost a quarter light-year from Sol, a year after departure, before achieving relative rest. Then, to come back three light-months at one thousand K.P.S. takes roughly seventy-two years. But the whole round trip as originally scheduled, with a one-year layover at Rustum, runs just about eighty-three years!
"Obviously there's some point in time beyond which we can actually get home quicker by staying with the original plan. This date lies after eight months of free fall, or not quite fourteen months from departure. We're only a couple of months from the critical moment right now; if we start back at once, we'll still have been gone from Earth for about seventy-six years. Each day we wait adds months to the return trip. No wonder there's impatience!"
"And the relativity clock paradox makes it worse," Teresa said.
"Well, not too much," Coffin decided. "The tau factor is 0.87. Shipboard time during eighty years of free fall amounts to about seventy years; so far the difference isn't significant. And anyhow, we'll all spend most of the time in deepsleep. What they're afraid of, the ones who want to go back, is that the Earth they knew will have slipped away from them."
She nodded. "Can't they understand it already has?" she said.
It was like a blade stabbed into Coffin. Though he could not see why that should be: surely he, of all men, knew how relentlessly time flowed. He had already come back once, to an Earth scarcely recognizable. The Society had been a kind of fixed point, but even it had changed; and he--like Kivi, like all of them--was now haunted by the fear of returning again and not finding any other spacemen whatsoever.
But when she spoke it--
* * * * *
"Maybe they're afraid to understand," he said.
"You keep surprising me, captain," said Teresa with a hint of her smile. "You actually show a bit of human sympathy."
And, thought a far-off part of Coffin, you showed enough to put me at ease by getting me to lecture you with safe impersonal figures. But he didn't mind. The fact was that now he could free-sit, face to face, alone, and talk to her like a friend.
"Since we could only save about seven years by giving up at once," he said, "I admit I'm puzzled why so many people are so anxious about it. Couldn't we go on as planned and decide things at Rustum?"
"I think not," said Teresa. "You see, nobody in his right mind wants to be a pioneer. To explore, yes; to settle rich new country with known and limited hazards, yes; but not to risk his children, his whole racial future, on a wild gamble. This group was driven into space by a conflict which just couldn't be settled at