"If what you say is true," said Sam, "it might be that the slightest contact with any substance of the moon would be sheer poison to a human being. A returning vessel could never be permitted to enter the earth's atmosphere, and decontamination would become one of the major branches of science." "That's entirely possible. It would complicate enormously the problems of establishing a moon-base. A speck of moondust inside the base might be as lethal as an unshielded reactor." Mary was looking out the kitchen window toward the thin crescent of moon that was setting over the city. She thought of Allan, who would soon be voyaging to that alien world. "It's like a trap up there in the sky. We should never have tried to reach it." "No--it's not like that at all," said Jim vigorously. "We'll solve whatever problems we find there. But think of it! We don't have to build a ship capable of crossing billions of light years of space to see what's out there. Something from out there has come to us and parked right in our own front yard. We have a thousand times more reason to go now!" Sam toyed with his toast and dunked it in the chocolate. "I think you ought to keep it quiet--until we really _know_, don't you." "Why? I'll run some more tests, sure. I'll plug every loophole there can possibly be. But unless I find something new I'm going to announce it. Why shouldn't I?" "I don't think Hennesey will like it, for one thing. Too sensational. Even when we actually land there and confirm your analyses by on-the-spot checks--it's still only a theory that the moon doesn't belong to this galaxy. You'll never be able to prove that." "What we've found already is proof enough!" "Not for Hennesey. He'll ask to see the shipping manifest by which the moon was transferred here. You know Hennesey." "Sure, I know Hennesey," said Jim bitterly. "And he doesn't count. Not in something like this. This is big, and important, and I'm going to announce it. I want the credit for discovering it. It'll be called Cochran's Theory, and some University will offer me at least an honorary Ph.D. Is that bad?" Sam shook his head. "Of course it's not bad. But I wonder what the public reaction will be like, and how about Congress--especially if this business about possible poisoning from moondust turns out to be correct? There might be a lot of pressure to cut funds and maybe cancel the whole moon project." "If moondust is lethal, there's no better time to be warned against it than right now!" * * * * * He spent the following week, eighteen hours a day, at the chemical analysis panel in the tracking station. As long as the moon was above the horizon, day or night, he kept experiments going--checking, re-checking, calibrating, searching for loopholes. There were no loopholes. There was no malfunction of equipment. The atoms of the moon's elements were not the same as those of the rest of the galaxy.