Free Tales of Pirx the Pilot by Stanislaw Lem

assignment.
    “The station is manned by astronomers—they’re sent out there, do their month’s service, and that’s that. The work is routine, requiring no specialized skills. Candidates used to be screened on the basis of the standard first- and second-degree tests. But that was before the accident. Now we need people who have undergone more rigorous testing. Pilots would be ideal, but you can’t very well farm a pilot out to a routine observatory. You can understand that.”
    Pirx could understand. The whole solar system was begging for pilots, astrogators, navigators—always in short supply, even in the best of times. But what “accident” was the commandant referring to? Pirx observed a prudent silence.
    “It’s a small station, situated in the most cockeyed place imaginable—not on the crater floor, as you’d expect, but just below the northern summit. There was a big to-do about the choice of location, international prestige rather than sound selenophysics being the deciding factor—as you’ll see in a moment. Anyhow, last year a section of the wall collapsed and wiped out the only road, making access difficult, and possible only by day. Plans were under way for a cable railway, but work was halted when it was decided to transfer the station down below in a year’s time. At night the station is cut off from the outside world. All radio communication is suspended. Why is that?”
    “Sir?”
    “Why does all radio communication cease?”
    That was the commandant for you. What had begun as a harmless briefing on his Mission had suddenly been turned into an exam! Pirx broke out into a sweat.
    “Since the Moon has no atmosphere or ionosphere, radio communication is maintained by ultrashortwave frequency… A network of relay stations, similar to TV transmitters, was constructed to—”
    The commandant, his elbows propped on the desktop, twiddled his ball-point in a display of forbearance as Pirx went on expounding on things any schoolchild would have known. He was venturing into territories where his limited knowledge left much to be desired.
    “These transmission lines”—he hurtled on, coming upon more familiar waters—“have been installed on both the Far Side and the Near Side. Eight are located on the Far Side, linking up Luna Base with Sinus Medii, Palus Somnii, Mare Imbrium—”
    “You can skip that,” the commandant suddenly interrupted in a fit of magnanimity. “Nor is it necessary to hypothesize on the origin of the Moon. Proceed.”
    Pirx blinked.
    “Radio interference occurs when the relay network enters the terminator … when one half of the network lies in darkness and the other half in light—”
    “I know what a terminator is. There’s no need to explain it,” the commandant said benignly.
    Pirx coughed and blew his nose. Still, he couldn’t go on coughing or blowing his nose forever.
    “In the absence of any lunar atmosphere, the Sun’s corpuscular radiation bombards the Moon’s crust, causing—uh—interference of the radio waves. This interference is what causes inter—”
    He was floundering.
    “The interference interferes—absolutely right!” said the commandant, coming to his aid. “But what causes the interference?”
    “A secondary radiation, known as the No—the No—”
    “Nov—” The commandant prodded gently.
    “The … Novinsky effect!” Pirx finally blurted out. But the interrogation didn’t end there.
    “And what produces the Novinsky effect?”
    This last question had him altogether stumped. There was a time when he’d known the answer, but he had since forgotten. He had gone into the exam with the facts down cold, like a juggler balancing a pyramid of wildly improbable things in his head. But the exam was over now. He was desperately going on about electrons, forced radiation, and resonances when he was cut short by a sympathetic head-shake from the commandant.
    “Uh-uh,” said the stern and uncompromising man. “And Professor Merinus