Henry Ohm leaped to his feet, stared across the intervening ground at igloo number 2, plainly visible through the clear plastic walls. Its door had just been flung violently open. Then Sofi Jokai scooted out and fled madly across the jagged surface of the asteroid. Hard on the girl's heels pounded R-7. The robot, Hen saw with a gulp, was waving a large wrench in one metal fist. "Oh-oh!" Hen muttered and plunged down the incline for the airlock. He shot a second glance through the transparent cur