"No," he smiled. "Less than three years from now. You see, seven light years is the greatest distance that separates the stars between here and Neosol. We've got a nice network of radio beams criss-crossing the pathway between here and Neosol. Oh," he admitted with a smile, "the triangulation beams will be arriving from now until a hundred years from now, but they're mostly check-beams, and the final beam from Earth to Neoterra will take the full time. But in the meantime we can refine our space charts using the network of beams once they start to arrive. And each time one of the triangulation check-beams gets home, we'll be able to refine the charts even more. But there's no sense in waiting for a century and a half." The sergeant looked at Paul. "You're certain you can fly with that bump on the head?" "Sure." "Why not let someone else take it." Paul shook his head. "It's my job," he said quickly. "But there must be someone else that can do it. What if you died?" "Oh, there are others trained in this sort of job in that case." "Why not let one of them take it, then?" Paul shook his head again. "I'm all right," he said. He realized that his insistence was too vigorous and that his reasons were too lame. But he could not let them know why it was so important that Paul Grayson go in person. If Haedaecker got wind of what Paul carried in his spacecraft, there would be hell to pay. He thought of a plausible excuse. "Most of them aren't on earth right now." "Couldn't you call one of them?" Paul smiled ruefully. "They're outside of the solar system." The sergeant nodded. "The Z-wave can't cross interstellar space," he said. It was a statement thrown in to display his knowledge to the technician from the Bureau of Astrogation, and also a leader for more conversation. Paul did not bite. "That's Haedaecker's Theory," added the sergeant. "Isn't it?" he added after another moment of silence. "Haedaecker's Theory is that the Z-wave propagates only in a region under the influence of solar activity," explained Paul. He looked out of the police car and saw the spaceport only a few moments away. Then he talked volubly to fill in the time so that he could be off without further questioning. Haedaecker had plenty of evidence to support his theory, but they all were missing one point that was as plain as the nose on Haedaecker's face. "We can talk with ease from the Zero Laboratory on Pluto to the Solar Lab on Mercury, to the boys who are working in the poisonous atmosphere of Jupiter, to the extra-terran paleontologists who are combing Venus," said Paul. "And the Radiation Laboratory sent a gang to try the five planets of Sirius. Again they got the Z-wave working after a bit of fiddling with the tuning. But we've not been able to get so much as a whisper from Sol to Proxima Centauri via Z-wave. What started Haedaecker thinking was the experiment they tried about ten years ago." Paul went on before anybody could interrupt.