in my spare time. There's radio noise from stars, you know. Just stuff that sounds like spatter static, and an occasional squawk. People have been listening to it for a long time, and researching, trying to work out why stellar radiation on those bands comes in such jagged bursts. It didn't seem natural."

He paused and smiled uncertainly, aware that the next thing he would say was the thing that would make him famous—an idea that had come to him while he listened—an idea as simple and as perfect as the one that came to Newton when he saw the apple fall.

"I decided it wasn't natural. I tried decoding it."

Hurriedly he tried to explain it away and make it seem obvious. "You see, there's an old intelligence trick, speeding up a message on a record until it sounds just like that, a short squawk of static, and then broadcasting it. Undergrounds use it. I'd heard that kind of screech before."

"You mean they broadcast at us in code?" asked the News.

"It's not exactly code. All you need to do is record it and slow it down. They're not broadcasting at us. If a star has planets, inhabited planets, and there is broadcasting between them, they would send it on a tight beam to save power." He looked for comprehension. "You know, like a spotlight. Theoretically, a tight beam can go on forever without losing power. But aiming would be difficult from planet to planet. You can't expect a beam to stay on target, over such distances, more than a few seconds at a time. So they'd naturally compress each message into a short half-second or one-second-length package and send it a few hundred times in one long blast to make sure it is picked up during the instant the beam swings across the target."

He was talking slowly and carefully, remembering that this explanation was for the newspapers. "When a stray beam swings through our section of space, there's a sharp peak in noise level from that direction. The beams are swinging to follow their own planets at home, and the distance between there and here exaggerates the speed of swing tremendously, so we wouldn't pick up more than a bip as it passes."

"How do you account for the number of squawks coming in?" the Times asked. "Do stellar systems rotate on the plane of the Galaxy?" It was a private question; he spoke impulsively from interest and excitement.

The radio decoder grinned, the lines of strain vanishing from his face for a moment. "Maybe 

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