"It's the nose of a message missile--dropped from a guided missile," Burl announced. "And--look!" He dramatically pointed the beam of his flashlight upon its side. There, written in black, heat-resistant paint, were the words: _To the Denning Andes Expedition, from U.S. Air Force Base, California Region. By Guided Missile Post by Moon Base control, Ptolomaeus Crater. Official. Open Without Delay._ Chapter 2. _The Valley of Stolen Sunlight_ For a moment all three were silent with amazement. "From California--and Moon Base--for _us_?" gasped Burl, finally. "But why? What can they want of us?" His father frowned. "Only way to find out is to open it and see." He squatted down to study the cylinder closer. Burl pointed a finger at the nose. "Looks like a crack there. Maybe it unscrews. Let's lift it." It was not as heavy as it had appeared, for, like all rocket missiles, it was made of the light but tough alloys that were necessary to conserve weight-lift costs and fuel reserves. They stood it upright and tried to turn the top. After a little resistance, it unscrewed slowly. Inside, they found a rolled document bearing the seal of the United States Air Force. Burl took it out, and unfolded it with unsteady hands. His father read over his shoulder. Gonzales poked at the empty cylinder, impatiently. Finally, he burst out, "What does it say? What do they want?" Burl turned to him. "It's unbelievable! It's--it's just so darned surprising! The dimness of the days, the drop in temperature--it wasn't just around here! It was all over the world!" Quickly, he went on to tell the Peruvian what they had just learned. The communication was from the U.S. Space Commission and it had been directed on its flight from California by the Moon Base, because only from the satellite could the exact location of the Dennings be spotted. It seemed that the Dennings were the only scientifically trained personnel close to the point on Earth where the disturbance originated. This also accounted for the blanketing of radio waves in their vicinity. Several airplanes had tried to locate them, but strange disturbances in the ether and atmosphere had made it impossible to establish contact. Also, the back reaches of the Andes were poorly mapped and treacherous in air currents, even in normal times. "During the last week, a certain fraction of the Sun's light and energy reaching the Earth has been diverted. It has been bent or focused in much the same way that a lens bends light rays--and the point to which it has been directed is a spot only seven miles from here! Over that last mountain range," said Burl, pointing. Gonzales followed his finger. "Just over the mountains lies the source of the trouble," said Burl excitedly. "And we're the nearest to it. They want us to go over there, see what it is, stop it, or report back. It took the telescopes in Moon Base to locate us and to track the center of the trouble!"