"Radiation?" Ekstrohm suggested. "The planet is very low in radiation from mineral deposits, and the atmosphere seems to shield out most of the solar output. Any little dose of radiation might knock off these critters." "I don't know about that. Maybe it would work the other way. Maybe because they have had virtually no radioactive exposure and don't have any R's stored up, they could take a _lot_ without harm." "Then maybe it was the shockwave we set up. Or maybe it's sheer xenophobia. They curl up and die at the sight of something strange and alien--like a spaceship." "Maybe," the captain admitted. "At this stage of the game anything could be possible. But there's one possibility I particularly don't like." "And that is?" "Suppose it was _not_ us that killed these aliens. Suppose it is something right on the planet, native to it. I just hope it doesn't work on Earthmen too. These critters went real sudden." * * * * * Ekstrohm lay in his bunk and thought, the camp is quiet. The Earthmen made camp outside the spaceship. There was no reason to leave the comfortable quarters inside the ship, except that, faced with a possibility of sleeping on solid ground, they simply had to get out. The camp was a cluster of aluminum bubbles, ringed with a spy web to alert the Earthmen to the approach of any being. Each man had a bubble to himself, privacy after the long period of enforced intimacy on board the ship. Ekstrohm lay in his bunk and listened to the sounds of the night on Yancy-6 138. There was a keening of wind, and a cracking of the frozen ground. Insects there were on the world, but they were frozen solid during the night, only to revive and thaw in the morning sun. The bunk he lay on was much more uncomfortable than the acceleration couches on board. Yet he knew the others were sleeping more soundly, now that they had renewed their contact with the matter that had birthed them to send them riding high vacuum. Ekstrohm was not asleep. Now there could be an end to pretending. He threw off the light blanket and swung his feet off the bunk, to the floor. Ekstrohm stood up. There was no longer any need to hide. But what was there to do? What had changed for him? He no longer had to lie in his bunk all night, his eyes closed, pretending to sleep. In privacy he could walk around, leave the light on, read. It was small comfort for insomnia. Ekstrohm never slept. Some doctors had informed him he was mistaken about this. Actually, they said, he did sleep, but so shortly and fitfully that he forgot. Others admitted he was absolutely correct--he _never_ slept. His body processes only slowed down enough for him to dispel fatigue poisons. Occasionally he fell into a waking, gritty-eyed stupor; but he never slept. Never at all. Naturally, he couldn't let his shipmates know this. Insomnia would ground him from the Exploration Service, on physiological if not psychological grounds. He had to hide it.