"It could be," he said in a carefully detached voice. "We didn't draw much power by comparison with the amount that came. But the ionization is an ultra-violet effect. Atmospheric gases don't ionize too easily. After all, if the solar constant dropped a very little, it might mean a terrific drop in the ultra-violet part of the spectrum—and that's what makes ions of oxygen and nitrogen and hydrogen and such. The ion-drop could easily be fifty times as great as the drop in the solar constant. And we're drawing power from the little that's left."
Riki stood very still. The cold was horrible. Had there been a wind, it could not have been endured for an instant. But the air was motionless. Yet its coldness was so great that the inside of one's nostrils ached, and the inside of one's chest was aware of chill. Even through the cold-garments there was the feeling as of ice without.
"I'm beginning," said Bordman, "to suspect that I'm a fool. Or maybe I'm an optimist. It might be the same thing. I could have guessed that the power we could draw would drop faster than our need for power increased. If we've drained the aurora of its light, we're scraping the bottom of the barrel. And it's a shallower barrel than one would suspect."
There was stillness again. Riki stood mousy-quiet. When she realizes what this means, thought Bordman grimly, she won't admire me so much. Her brother's built me up. But I've been a fool, figuring out excuses to hope. She'll see it.
"I think," said Riki, "that you're telling me that after all we can't store up heat to live on, down in the mine."
"We can't," agreed Bordman. "Not much, nor long. Not enough to matter."
"So we won't live as long as Ken expects?"
"Not nearly as long," said Bordman. "He's hoping we can find out things to be useful back on Lani II. But we'll lose the power we can get from our grid long before even their new grids are useless. We'll have to start using our reserve power a lot sooner. It'll be gone—and us with it—before they're really in straits for living-heat."
Riki's teeth began to chatter.
"This sounds like I'm scared," she said angrily, "but I'm not! I'm just freezing. If you want to know, I'd a lot rather have it the way you say. I won't have to grieve over anybody, and they'll be too busy to grieve for me.... Let's go inside while it's still warm."