"If they are black holes. The computer analysis says they can't be. They're drawn out now, elongated like worms, and the second one is different," Sand said. "Look at its traces. High radiation in the atmosphere. It's making more noise than the first. And remember the sighting—it sparked like a sonofabitch when it came through the air. Walt? How did you describe the first?"

"Two long, bright flares at first. Then small, much less bright."

Post's hand worked restlessly with his shirt collar.

"Hell, it could be a plain old meteor, too," Arthur said.

"Meteors spark. Would an amateur know the difference?"

"But what about the radiation? Every guess we make, we go out on a limb," Sand said.

"No kidding," Post chuckled.

Samshow leaned forward. "But let's assume the second one was a more spectacular fall. Bigger object?"

"The traces could indicate a slightly bigger object. Or . . . explosive disturbances along its path?" Sand suggested.

Arthur listened, amused by the creative confusion. "What would release radiation?"

"Small black holes might," Post said. "But they'd be considerably smaller in cross section than a few centimeters, if they massed in at only a hundred million tons. I don't think they'd make much of a show at all. And if they're putting out gamma rays at a high enough level to irradiate sailors dozens of kilometers away ..." His face fell. "They're not going to last very long. Besides, they can't be black holes, remember?"

"What do you mean, about them not lasting very long?" Samshow asked.

Post made a frustrated face. "They're not black holes. We can be pretty sure of that. But, all right, black holes put out radiation all the time. When they're big, they're colder than the universe around them, but they're not at absolute zero . . . Still, the effect is a net intake of energy. But after tens of billions of years, or if they were created small to begin with, they become much hotter, and lose their mass much more rapidly, percentage-wise. When they drop down to about ten thousand tons of mass, they explode all at once—ten thousand tons of pure energy." He worked quickly on his calculator. "Not enough to cause much damage if they're deep inside the Earth, actually."

"But what we have is a hundred million tons," Sand said. "Or maybe twice that, if we count the second object."

"I was getting to that," Post said, holding up a hand. "The worst case is that the black hole, or holes, could suck up mass inside the Earth, grow, and eventually suck up all of the Earth."

The group looked at each other, wondering how much they were willing to believe, how far out they might be willing to go.

"That wouldn't make sense if the aliens had any intention of using the Earth's raw material to make more spaceships," Post said.

"What about something else, something we know nothing about?" Arthur persisted.

Samshow laughed. "You're saying we know anything about black holes?"