tube. The bright star in the middle of the hoop bobbed around, then settled down and began to drift offscreen. A collection of indistinct lights swam into view on the screen, and the director took over the controls from the assistant.
“This was their local group of galaxies,” the director said. “It’s smaller than our own local group. Basically it consists only of two spiral galaxies bound gravitationally to one another, each with its attendant swarm of satelhte galaxies.”
He made a fine adjustment, and the image sharpened. Bram could see the two spirals, like tiny glowing coiled springs, surrounded by hazy dots.
“They had a name for our own local group, or rather the constellation it appeared in from their point of view,” the director went on. “They called it the Hunting Dogs.”
Bram whispered to Voth again, and the director said, “That’s all right, youngster. What did you want to know?”
“What’s a dog?” Bram said in a small voice.
“It was another life form that the humans bred for companionship and various simple chores. We gather that it was intelligent but not as intelligent as Man.”
“Did they make them?”
“We don’t know,” the director said impatiently. “We think they may have been adapted from an existing life form.”
“There are dogs mentioned in human literature, Bram,” Voth said. “You’ll read about them when you grow older.”
“The human radio beacon was not aimed at us here in the Dogs,” the director continued. “It was aimed beyond us at a very large cluster of galaxies in a constellation they called Virgo.” He paused. “Virgo was their term for a being who has not yet attained the female reproductive stage.” There must have been some kind of a warning signal from Voth; Bram could feel its echo in the swish of cilia in the arm that enfolded him. The director hurried on. “The Virgo cluster of galaxies consists of well over a thousand galaxies, and we believe it to be the center of a supercluster of which our local group and the human local group are outriders. So the humans did a very intelligent thing. Can you guess what that is?”
“They wanted to send their message to a whole lot of galaxies all at the same time,” Bram said promptly.
“Exactly right, young Bram,” the director said with a pleased expression. “You were right about him, Voth-shr-voth.” The two mirror eyes aimed in Bram’s direction turned blue again. “That beam of radio waves will keep spreading outward for tens of millions of years, and they wanted it to encounter the greatest possible number of galaxies. Here, I think we can hold this image while I show you the Virgo cluster. It’s in our daytime sky now, on the opposite side of the world, but one of our orbiting telescopes will have it in view.”
He spoke to his assistant. A moment later, to Bram’s consternation, the wriggly glowworms on the screen snapped out of existence, and the hoop was filled with a spectacular shower of sparks and flares.
“The richest imaginable target,” the director said. “That one elliptical galaxy in the center alone contains three thousand billion suns, compared to our paltry two hundred billion, in addition to a halo of ten thousand globular clusters. The humans, long ago, would have had much the same view we’re seeing now, but from almost twice as far away. The human radio waves haven’t reached it yet. They won’t for another thirty million years.”
To Bram’s relief he switched back to the other side of the sky. The human galaxy was still there, one of those bright midges.
“The larger of the two is the one they called Andromeda,” the director said. “It’s the other one we want.”
The image centered and grew in swoops, becoming alternately blurred and sharp as the director adjusted his focus. At last it filled the hoop, a jeweled whorl with an incandescent center. Bram remembered that the jewels would be foreground stars, but that did not detract from