Rick understood. The sources in space studied by the radio telescopes were fixed, in the same sense that the stars themselves were fixed. Of course everything in the galaxy--even in the universe--was in motion, but in spite of the enormous velocities, the change in location would not be particularly apparent in a short time, or even in a lifetime.
A short distance away was a wonderful example of this kind of motion. In the great pyramid of Khufu, Rick had read, a channel had been left so the light of the North Star could shine on the altar of Isis. The channel was still there. But in over three thousand years the slight, slow wobbling of the earth on its axis had caused a shift. What was then the North Star was now Thuban, in the constellation of Draco the Dragon. The present North Star, Polaris, which is not exactly at the celestial north pole, did not shine on the altar. Nor would the next star to become the northern marker--bright Vega. But if the pyramids were still standing after twenty-seven thousand years had passed, the cycle of movement would be complete, and Thuban would again shine through the channel to the altar of a forgotten Egyptian goddess.
It gave Rick a shiver to think about it. Even now, the pyramids were old enough to have seen a change of north stars. They looked good for another three thousand years or more. It would take a lot of time to erode away that much massive stone.
Then he stopped thinking about it, because the telescope was in motion again, and there was work to be done.
It was late night before the scientists were satisfied. The boys rode back with Hassan, very thoughtful about the day's events. Now they had both the little statue and the even greater mystery of the space signals to think about.
Clearly, the strange signal was not of local origin. The scientists rejected the idea that it came from trouble in the circuit. But it was no natural heavenly object. What was it?
Tomorrow, Winston had said, they would decide on the next step. Right now all hands were too tired to think clearly. The boys agreed that the statement applied to them.
"Shall we eat?" Rick asked as they approached the hotel.
"Let's have a sandwich sent up," Scotty suggested. "I don't feel like waiting in a dining room, even if one is open this late."