"Because Mars has a weaker gravity pull, being smaller than the earth. And here, out in space, there is no gravity to keep life down. A plant grows and grows as long as it lives, unlike an animal. This huge asteroid has been growing for ages, millions of years, maybe. What's to stop it? No gravity pressing down. Perhaps it can live purely on the mineral matter of the meteors which fall. Maybe it's only a seed, with food-matter stored up inside. Who knows?" * * * * * Johnny and Joan came out from the galley. Joan said: "Mama, I'm hungry." Marcia laughed. "We never did have that picnic, Burt." "Uh-huh. You're right--so we didn't. But this damn asteroid almost did--on us." "Papa," Johnny said, "let's land someplace and have a picnic." "Go to hell," Burt said, forgetting he was speaking to a boy, his boy. "Burt! Then you wonder why Johnny curses. Just watch your language in front of the children, Burt Rogers!" "Okay," he said. "But no more picnics. I'm going to report this thing to the police, and they'll blow it out of the sky with atomite. Then we'll have a nice meal at home. But no more picnics, ever. I'll take the kids to the Canalport swimming pool on week-ends--half-way around the planet. But no more picnics." "Please, papa," Johnny said. Marcia nodded. "Look. He's being polite." Burt sighed. He knew he could get away with it this week-end. But later on in the month--or certainly next month--there would be more picnics.