were thick. He had to move the screening adjustment almost to its last notch before the vapor patterns blocked out and the stars were bright and unwavering and ready to be photographed. He inserted the first plate and snapped the picture of the stars whose names he knew but whose patterns were wrong, some subtly, some blatantly.

There was something he was overlooking. Some other factor, not taken into account. He developed the first plates and compared them with the star charts of Earth as it had been before they left it, and he shook his head. Whatever the factor was, it eluded him. He went back to work.

"Oh, here you are, Hugh."

He jumped at the sound of Carhill's voice. He had been working almost completely by habit, slowly swinging the telescope across the sky and snapping the plates. And trying to think.

"Why waste time on that?" Carhill added bitterly. "Who's ever going to see our records now?"

Behind Carhill, several of the other old ones nodded. Hugh was surprised that they had managed to come back to the ship without his hearing them. But of course they had come back in at sundown, as usual on a routine check, and now they were gathering to compile their reports. Hugh looked from face to face, wondering if he too was as numb and dazed and haggard appearing as they were. He probably was.

"What do you suggest, Amos?" he said.

"I say there's no use going on," Carhill said flatly. "You've all run your tests. And what have you found? No fossils. Not even a single-celled life form in the ocean. No way even to tell how many millions of years it's been."

"Maybe it hasn't been so long," Haines said. "Maybe something happened here fairly recently, and the people all went to some other system—to one of the Centauri planets, maybe."

Amos Carhill laughed bitterly. "You can say that in the face of the evidence? We know that millions of years have passed. Nothing's the same. Even the tides are three times what they were. It's obvious what happened. The sun novaed. Novaed and cooled. Do you really believe that our race has lasted that long, on some nearby system?"

is voice rose. He glared about at the others. He threw back his head suddenly and laughed, and the laughter echoed and re-echoed off the steel walls.

"I say let's die now!" Carhill cried. "There's no use going on. Hugh was right, as usual. We shouldn't have tried to come back. We've been fools, all these years, thinking we had a world to come home to."

The people muttered, crowded closer. They pushed into the observation room, shoved nearer to it in the outside corridor. They muttered in a rising note of panic as the numbing shock that gripped them gave way.

"Why not die here?" Martha Carhill's voice rose shrill above the sound of her husband's laughter. "We should have died here millions of years ago!"

Hugh McCann looked at her and at Amos and at all the others. He sighed. Why not? Why go on? There was no answer. Even a pragmatist gave up eventually, when the facts were all against him.

He glanced down at the reports on the table. All the routine reports, gathered together into routine form, written up in routine terminology. Reports on an Earth-type planet that just happened to be the Earth itself.

And then, quite suddenly, the obvious, satisfactory answer came to him. The factors clicked into place, and he wondered why he hadn't thought of them long ago. He looked up from the reports, at the people on the verge of panic, and he knew what to say to quiet them. He had the factors now.

"No!" he cried. "You're wrong. There's no reason at all to assume that our race is dead!"

Amos Carhill stopped laughing and stared at him and the others stared also and none of them believed him at all.

"It's simple!" he cried. "Why has so much time passed outside the ship