"Right!"

"I never did get quite clear on the subject of Planet P," drawled Rokesmith. "Just how was it discovered?"

Captain Wanderman cleared his throat. "Few people are; even the experts don't know much about it.

"Its existence was first surmised and calculated in 1931—about a hundred years ago—by Professor William H. Pickering of Jamaica. He observed that the planet Uranus was being displaced from its proper orbit. Of course, this perturbation could be due only to the influence of another planet, he thought. But there was no other body known at that time which could account for the drag. Thus, the Professor computed mathematically the existance, approximate size, and position of an unknown body which would account for the odd behavior of Uranus. This he calculated to be a giant planet of a diameter of approximately 44,000 miles, in mass the third greatest in the solar system. He puts its distance to range in an eliptical orbit of from 5,000 million miles to 9,000 million miles from the sun. This, of course, made it extra-Plutonian in position. Its year would be in length about 656 Earthly years. He gave it the temporary name of Planet P.

"Planet P's existence was further indicated by the orbits of some sixteen comets, also affected by a drag which the theoretical planet made perfectly accountable. Last year the planet Neptune had finally arrived in the position where it, too, would be affected by this body. You understand: the astronomers, calculating both known and theoretical factors, determined that, if this Planet P existed, an irregularity in Neptune's behavior would be discovered at this particular time. The predicted irregularity arrived on time; thus, due to this added information, our astronomers were able to find out precisely where the new planet should be sought. And they found it. It is indeed an immense thing, shows a perceptible disc even at its great distance from Earth. We may anticipate something different when we arrive."

Days went by. Endless days marked only by the chronometer in the unchanging blackness of the celestial void. The tiny pinpoints of myriad stars glowed unchangingly. Behind them, a few planets grew more and more minute, each in turn finally being blotted out by the corona of the sun. Jupiter's orbit was left behind; they saw the great ringed planet loom up to one side and fade away as all the others had done. But this was not with the flashing speed of objects and cities passing the rocket-vehicle on Earth. It was a matter of days before each change could be realized, 

 Prev. P 8/16 next