again.”
“This I was able to check independently. I am an astronomer, after all.”
“That is true. Let me hear what you have to say then, while we walk.”
“Then, sir, consider that for a long time our astronomers have believed that two general classes of planetary bodies existed. First, the planets which formed at distances far enough from their stellar nucleus to become cool enough to capture hydrogen. These would be large planets rich in hydrogen, ammonia and methane. We have examples of these in the giant outer planets. The second class would include those planets formed so near the stellar center that the high temperature would make it impossible to capture much hydrogen. These would be smaller planets, comparatively poorer in hydrogen and richer in oxygen. We know that type very well since we live on one. Ours is the only solar system we know in detail, however, and it has been reasonable for us to assume that these were the only two planetary classes.”
“I take it then that there is another.”
“Yes. There is a super-dense class, still smaller, poorer in hydrogen, than the inner planets of the solar system. The ratio of occurrence of hydrogen-ammonia planets and these super-dense water-oxygen worlds of theirs over the entire Galaxy—and remember that they have actually conducted a survey of significant sample volumes of the Galaxy which we, without interstellar travel, cannot do—is about 3 to 1. This leaves them seven million super-dense worlds for exploration and colonization.”
The Industrialist looked at the blue sky and the green-covered trees among which they were making their way. He said, “And worlds like ours?”
The Astronomer said, softly, “Ours is the first solar system they have found which contains them. Apparently the development of our solar system was unique and did not follow the ordinary rules.”
The Industrialist considered that. “What it amounts to is that these creatures from space are asteroid-dwellers.”
“No, no. The asteroids are something else again. They occur, I was told, in one out of eight stellar systems, but they’re completely different from what we’ve been discussing.”
“And how does your being an astronomer change the fact that you are still only quoting their unsupported statements?”
“But they did not restrict themselves to bald items of information. They presented me with a theory of stellar evolution which I had to accept and which is more nearly valid than anything our own astronomy has ever been able to devise, if we except possible lost theories dating from Beforethewars. Mind you, their theory had a rigidly mathematical development and it predicted just such a Galaxy as they describe. So you see, they have all the worlds they wish. They are not land-hungry. Certainly not for our land.”
“Reason would say so, if what you say is true. But creatures may be intelligent and not reasonable. Our forefathers were presumably intelligent, yet they were certainly not reasonable. Was it reasonable to destroy almost all their tremendous civilization in atomic warfare over causes our historians can no longer accurately determine?” The Industrialist brooded over it. “From the dropping of the first atom bomb over those islands—I forget the ancient name—there was only one end in sight, and in plain sight. Yet events were allowed to proceed to that end.”
He looked up, said briskly, “Well, where are we? I wonder if we are not on a fool’s errand after all.”
But the Astronomer was a little in advance and his voice came thickly. “No fool’s errand, sir. Look there.”
VI
Red and Slim had trailed their elders with the experience of youth, aided by the absorption and anxiety of their fathers. Their view of the final object of the search was somewhat obscured by the underbrush behind which they remained.
Red said, “Holy Smokes. Look at that. It’s all shiny silver or something.”
But it was Slim who was really excited. He caught at the other. “I know what this is. It’s a space-ship. That must be why my father came here. He’s one of the biggest astronomers in the world and your father would have to call him if a space-ship landed on his estate.”
“What are you talking about? Dad didn’t even know that thing was there. He only came here because I told him I heard the thunder from here. Besides, there isn’t any such thing as a space-ship.”
“Sure, there is. Look at it. See those round things. They are ports. And you can see the rocket tubes.”
“How do you know so much?”
Slim was flushed. He said, “I read about them. My father has books about them. Old books. From Beforethewars.”
“Huh. Now I know you’re making it up. Books from Beforethewars!”
“My father has to have them. He teaches at the University. It’s his job.”
His voice had risen and Red had to pull at him. “You want them to hear us?” he whispered indignantly.
“Well, it is, too, a space-ship.”
“Look here, Slim, you mean that’s a ship from another world.”
“It’s got to be. Look at my father going round and round it. He wouldn’t be so interested if it was anything else.”
“Other worlds! Where are there other worlds?”
“Everywhere. How about the planets? They’re worlds just like ours, some of them. And other stars probably have planets. There’s probably zillions of planets.”
Red felt outweighed and outnumbered. He muttered, “You’re crazy!”
“All right, then. I’ll show you.”
“Hey! Where are you going?”
“Down there. I’m going to ask my father. I suppose you’ll believe it if he tells you. I suppose you’ll believe a Professor of Astronomy knows what—”
He had scrambled upright.
Red said, “Hey. You don’t want them to see us. We’re not supposed to be here. Do you want them to start asking questions and find out about our animals?”
“I don’t care. You said I was crazy.”
“Snitcher! You promised you wouldn’t tell.”
“I’m not going to tell. But if they find out themselves, it’s your fault, for starting an argument and saying I was crazy.”
“I take it back, then,” grumbled Red.
“Well, all right. You better.”
In a way, Slim was disappointed. He wanted to see the space-ship at closer quarters. Still, he could not break his vow of secrecy even in spirit without at least the excuse of personal insult.
Red said, “It’s awfully small for a space-ship.”
“Sure, because it’s probably a scout-ship.”
“I’ll
