Moving with unnecessary quiet, since he could hardly have been heard above the noise of the jet in any case and since both Ross and Cargraves were giving very fair imitations of rocket motors themselves, he climbed out of the hammock and monkey-footed up to the pilots' seats. He dropped into Morrie's chair, feeling curiously but pleasantly light under the much reduced acceleration.

The moon, now visibly larger and almost painfully beautiful, hung in the same position in the sky, such that he had to let his gaze drop as he lay in the chair in order to return its stare. This bothered him for a moment—how were they ever to reach the moon if the moon did not draw toward the point where they were aiming?

It would not have bothered Morrie, trained as he was in a pilot's knowledge of collision bearings, interception courses, and the like. But, since it appeared to run contrary to common sense, Art worried about it until he managed to visualize the situation somewhat thus: if a car is speeding for a railroad crossing and a train is approaching from the left, so that their combined speeds will bring about a wreck, then the bearing of the locomotive from the automobile will not change, right up to the moment of the collision.

It was a simple matter of similar triangles, easy to see with a diagram but hard to keep straight in the head. The moon was speeding to their meeting place at about 2000 miles an hour, yet she would never change direction; she would simply grow and grow and grow until she filled the whole sky.

He let his eyes rove over her face, naming the lovely names in his mind, Mare Tranquilitatis, Oceanus Procellarum, the lunar Apennines, LaGrange, Ptolemous, Mare Imbrium, Catharina. Beautiful words, they rolled on the tongue.

He was not too sure of the capitals of all the fifty-one United States and even naming the United Nations might throw him, but the geography- or was it lunography? -of the moon was as familiar to him as the streets of his home town.

This face of the moon, anyway—he wondered what the other face was like, the face the earth has never seen.

The dazzle of the moon was beginning to hurt his eyes; he looked up and rested them on the deep, black velvet of space, blacker by contrast with the sprinkle of stars.

There were few of the really bright stars in the region toward which the Galileo was heading. Aldebaran blazed forth, high and aft, across the port from the moon. The right-hand frame of the port slashed through the Milky Way and a small portion of that incredible river of stars was thereby left visible to him. He picked out the modest lights of Aries, and near mighty Aldebaran hung the ghostly, fairy Pleiades, but dead ahead, straight up, were only faint stars and a black and lonely waste.

He lay back, staring into this remote and solitary depth, vast and remote beyond human comprehension, until he was fascinated by it, drawn into it. He seemed to have left the warmth and safety of the ship and to be plunging deep into the silent blackness ahead.

He blinked his eyes and shivered, and for the first time felt himself wishing that he had never left the safe and customary and friendly scenes of home. He wanted his basement lab, his mother's little shop, and the humdrum talk of ordinary people, people who stayed home and did not worry about the outer universe.

Still, the black depths fascinated him. He fingered the drive control under his right hand. He had only to unlock it, twist it all the way to the right, and they would plunge ahead, nailed down by unthinkable acceleration, and speed on past the moon, too early for their date in space with her. On past the moon, away from the sun and the earth behind them, on an on and out and out, until the thorium burned itself cold or until the zinc had boiled away, but not to stop even then, but to continue forever into the weary years and the bottomless depths.

He blinked his eyes and then closed them tight, and gripped both arms of the chair.

"ARE YOU ASLEEP?" THE VOICE in his ear made Art jump; he had still had his eyes closed—it startled him. But it was only Doc, climbing up behind him.

"Oh! Good morning, Doc. Gee, I'm glad to see you. This place was beginning to give me the jim-jams."

"Good morning to you, if it is morning. I suppose it is morning, somewhere." He glanced at his watch. "I'm not surprised that you got the willies, up here by yourself. How would you like to make this trip by yourself?"

"Not me."

"Not me, either. The moon will be just about as lonely but it will feel better to have some solid ground underfoot. But I don't suppose this trip will be really popular until the moon has some nice, noisy night clubs and a bowling alley or two." He settled himself down in his chair.

"That's not very likely, is it?"

"Why not? The moon is bound to be a tourists' stop some day—and have you ever noticed how, when tourists get somewhere new, the first thing they do is to look up the same kind of entertainments they could find just as easily at home?"

Art nodded wisely, while tucking the notion away in his mind. His own experience with tourists and travel was slight—until now! "Say, Uncle, do you suppose I could get a decent picture of the moon through the port?"

Cargraves squinted up at it. "Might. But why waste film? They get better pictures of it from the earth. Wait until we go into a free orbit and swing ship. Then you can get some really unique pics—the earth from space. Or wait until we swing around the moon."

"That's what I really want! Pictures of the other side of the moon."

"That's what I thought." Cargraves paused a moment and then added, "But how do you know you can get any?"

"But—Oh, I see'. what you mean. It'll be dark on that side."

"That's not exactly what I meant, although that figures in, too, since the moon will be only about three days past ‘new moon' -- ‘new moon,' that is, for the other side. We'll try to time it to get all the pics you want on the trip back. But that isn't what I mean: how do you know there is any back side to the moon? You've never seen it. Neither has any one else, for that matter."

"But- there has to -I mean, you can see..."

"Did I hear you say there wasn't any other side to the moon, Doc?" It was Ross, whose head had suddenly appeared beside Cargraves'.

"Good morning, Ross. No, I did not say, there was no other side to the moon. I had asked Art to tell me what leads him to think there is one."

Ross smiled. "Don't let him pull your leg, Art. He's just trying to rib you."

Cargraves grinned wickedly. "Okay, Aristotle, you picked it. Suppose you try to prove to me that there is a far side to the moon."

"It stands to reason."

"What sort of reason? Have you ever been there? Ever seen it?"

"No, but-"

"Ever met anybody who's ever seen it? Ever read any accounts by anybody who claimed to have seen it?"

"No, I haven't, but I'm sure there is one."

"Why?"

"Because I can see the front of it."

"What does that prove? Isn't your experience, up to now, limited to things you've seen on earth? For that matter I can name a thing you've seen on earth that hasn't any back side."

"Huh? What sort of a thing? What are you guys talking about?" It was Morrie this time, climbing up on the other side.

Art said, "Hi, Morrie. Want your seat?"

"No, thanks. I'll just squat here for the time being." He settled himself, feet dangling. "What's the argument?"

"Doc," Ross answered, "is trying to prove there isn't any other side to the moon."

"No, no, no," Cargraves hastily denied. "And repeat ‘no.' I was trying to get you to prove your assertion that there was one. I was saying that there was a phenomenon even on earth which hasn't any back side, to nail down Ross's argument from experience with other matters—even allowing that earth experience necessarily applies to the moon, which I don't."