Hunt frowned for a while and studied the detail of the Farside hemisphere of the model. "And yet, you must have known about all this for years," he said, looking up. "Why the devil did you wait for us to call you?"

Steinfield showed his hands again and held the pose for a second or two. "Well, you UNSA people are pretty smart cookies. I figured you already knew about all this."

"We should have picked it up sooner, I admit," Hunt agreed. "But we've been rather busy."

"Guess so," Steinfield murmured. "Anyhow, there's even more to it. I've told you all the consistent things. Now I'll tell you some of the funny things. . . ." He broke off as if just struck by a new thought. "I'll tell you about the funny things in a second. How about a cup of coffee?"

"Great."

Steinfield lit a Bunsen burner, filled a large laboratory beaker from the nearest tap, and positioned it on a tripod over the flame. Then he squatted down to rummage in the cupboard beneath the bench and at last emerged triumphantly with two battered enamel mugs.

"First funny thing: The distribution of samples that we dig up on Farside that have a history of recent radioactive exposure doesn't match the distribution or strength of the activity sources. There ought to be sources clustered in places where there aren't."

"How about the meteorite storm including some highly active meteorites?" Hunt suggested.

"No, won't wash," Steinfield answered, looking along a shelf of glass jars and eventually selecting one that contained a reddish-brown powder and was labeled "Ferric Oxide." "If there were meteorites like that, bits of them should still be around. But the distribution of active elements in the garbage is pretty even—about normal for most rocks." He began spooning the powder into the mugs. Hunt inclined his head apprehensively in the direction of the jar.

"Coffee doesn't seem to last long around here if you leave it lying around in coffee jars," Steinfield explained. He nodded toward a door that led into the room next door and bore the sign RESEARCH STUDENTS. Hunt nodded understandingly.

"Vaporized?" Hunt tried.

Again Steinfield shook his head.

"In that case they wouldn't have been in proximity to the rock long enough to produce the effects observed." He opened another jar marked "Disodium Hydrogen Phosphate." "Sugar?"

"Second funny thing," Steinfield continued. "Heat balance. We know how much mass came down, and from the way it fell, we can figure its kinetic energy. We also know from statistical sampling how much energy needed to be dissipated to account for the melting and structural deformations; also, we know how much energy gets produced by underground radioactivity and where. Problem: The equations don't balance; you'd need more energy to make what happened happen than there was available. So, where did the extra come from? The computer models of this are very complex and there could be errors in them, but that's the way it looks right now."