Inherit the Stars

by James P. Hogan

  "First, two assumptions. One: the natural unit of time on any world is the day—that is, the time it takes the planet to rotate on its axis . . ."

  "Assuming it rotates," somebody tossed in.

  "That was my second assumption. But the only cases we know of where there's no rotation—or where the orbital period equals the axial period, which amounts to the same thing—occur when a small body orbits close to a far more massive one and is swamped by gravitational tidal effects, like our Moon. For that to happen to a body the size of a planet, the planet would have to orbit very close to its parent star—too close for it to support any life comparable to our own."

  "Seems reasonable," Caldwell said, looking around the table. Various heads were nodding assent. "Where do we go from there?"

  "Okay," Hunt resumed. "Assuming it rotates and the day is its natural unit of time—if this complete table represents one full orbit around its sun, there are seventeen hundred days in its year, one entry for each."

  "Pretty long," someone hazarded.

  "To us, yes: at least, the year-to-day ratio is big. It could mean the orbit is large, the rotational period short, or perhaps a bit of both. Now look at the major number groups—the ones tagged with the heavy alphabetic labels. There are forty-seven of them. Most contain thirty-six numbers, but nine of them have thirty-seven—the first, sixth, twelfth, eighteenth, twenty-fourth, thirtieth, thirty-sixth, forty-second, and forty-seventh. That seems a bit odd at first sight, but so would our system to someone unfamiliar with it. It suggests that maybe somebody had to do a bit of fiddling with it to make it work."

  "Mmm . . . like with our months."

  "Exactly. This is just the sort of juggling you have to do to get a sensible fit of our months into our year. It happens because there's no simple relationship between the orbital periods of planet and satellite; there's no reason why there should be. I'm guessing that if this is a calendar that relates to some other planet, then the reason for this odd mix of thirty-sixes and thirty-sevens is the same as the one that causes problems with our calendar: That planet had a moon,"

  "So these groups are months," Caldwell stated.

  "If it's a calendar—yes. Each group is divided into three subgroups—weeks, if you like. Normally there are twelve days in each, but there are nine long months, in which the middle week has thirteen days."

  Danchekker looked for a long time at the sheet of paper, an expression of pained disbelief spreading slowly across his face.

  "Are you proposing this as a serious scientific theory?" he queried in a strained voice.

  "Of course not," Hunt replied. "This is all pure speculation. But it does indicate some of the avenues that could be explored. These alphabetic groups, for example, might correspond to references that the language people might dig from other sources—such as dates on documents, or date stamps on pieces of clothing or other equipment. Also, you might be able to find some independent way of arriving at the number of days in the year; if it turned out to be seventeen hundred, that would be quite a coincidence, wouldn't it?"

  "Anything else?" Caldwell asked.

  "Yes. Computer correlation analysis of this number pattern may show hidden superposed periodicities; for all we know, there could have been more than one moon. Also, it should be possible to compute families of curves giving possible relationships between planet-to-satellite mass ratios against mean orbital radii. Later on you might know enough more to be able to isolate one of the curves. It might describe the Earth-Luna system; then again, it might not."

  "Preposterous!" Danchekker exploded.

  "Unbiased?" Hunt suggested.

  "There is something else that may be worth trying," Schorn interrupted. "Your calendar, if that's what it is, has so far been described in relative terms only—days per month, months per year, and so on. There is nothing that gives us any absolute values. Now—and this is a long shot—from detailed chemical analysis we are making some progress in building a quantitative model of Charlie's cell-metabolism cycles and enzyme processes. We may be able to calculate the rate of accumulation of waste materials and toxins in the blood and tissues, and from these results form an estimate of his natural periods of sleep and wakefulness. If, in this way, I could provide a figure for the length of the day, the other quantities would follow immediately."

  "If we knew that, then we'd know the planet's orbital period," said somebody else. "But could we get an estimate of its mass?"

  "One way might be by doing a structural analysis of Charlie's bone and muscle formations and then working out the power-weight ration," another chipped in.

  "That would give us the planet's mean distance from its sun," said a third.

  "Only if it was like our Sun."

  "You could get a check on the planet's mass from the glass and other crystalline materials in his equipment. From the crystal structure, we should be able to figure out the strength of the gravitational field they cooled in."

  "How could we get a figure for density?"

  "You still need to know the planetary radius."

  "He's like us, so the surface gravity will be Earthlike."

  "Very probable, but let's prove it."

  "Prove that's a calendar first."

  Remarks began pouring in from all sides. Hunt reflected with some satisfaction that at least he had managed to inject some spirit and enthusiasm into the proceedings.

  Danchekker remained unimpressed. As the noise abated, he rose again to his feet and pointed pityingly to the single sheet of paper, still lying in the center of the table.

  "All balderdash!" he spat. "There is the sum total of your evidence. There"—he slid his voluminous file, bulging with notes and papers, across beside it—"is mine, backed by libraries, data banks, and archives the world over. Charlie comes from Earth!"

  "Where's his civilization, then?" Hunt demanded. "Removed in an enormous celestial garbage truck?"

  Laughter from around the table greeted the return of Danchekker's own gibe. The professor darkened and seemed about to say something obscene. Caldwell held up a restraining hand, but Schorn saved the situation by interrupting in his calm, unruffled tone. "It would seem, ladies and gentlemen, that for the moment we must compromise by agreeing to a purely hypothetical situation. To keep Professor Danchekker happy, we must accept that the Lunarians evolved from the same ancestors as ourselves. To keep Dr. Hunt happy, we must assume they did it somewhere else. How we are to reconcile these two irreconcilables, I would not for one moment attempt to predict."

  Chapter Nine

  Hunt saw less and less of the Trimagniscope during the weeks that followed the progress meeting. Caldwell seemed to go out of his way to encourage the Englishman to visit the various UNSA labs and establishments nearby, to "see what's going on first-hand," or the offices in Navcomms HQ to "meet someone you might find interesting." Hunt was naturally curious about the Lunarian investigations, so these developments suited him admirably. Soon he was on familiar terms with most of the engineers and scientists involved, at least in the Houston vicinity, and he had a good idea of how their work was progressing and what difficulties they were encountering. He eventually acquired a broad overview of the activity on all fronts and found that, at least at the general level, the awareness of the whole picture that he was developing was shared by only a few privileged individuals within the organization.

  Things were progressing in a number of directions. Calculations of structural efficiency, based on measurements of Charlie's skeleton and the bulk supported by it, had given a figure for the surface gravity of his home planet, which agreed within acceptable margins of error with figures deduced separately from tests performed on the crystals of his helmet visor and other components formed from a molten state. The gravity field at the surface of Charlie's home planet seemed to have been not much different from that of Earth; possibly it was slightly stronger. These results were accepted as being no more than rough approximations. Besides, nobody knew how typical Charlie's physical build ha
d been of that of the Lunarians in general, so there was no firm indication of whether the planet in question had been Earth or somewhere else. The issue was still wide open.

  On equipment tags, document headings, and appended to certain notes, the linguistics section had found examples of Lunarian words which matched exactly some of the labels on the calendar, just as Hunt had suggested they might. While this proved nothing, it did add further plausibility to the idea that these words indicated dates of some kind.

  Then something else that seemed to connect with the calendar appeared from a totally unexpected direction. Site-preparation work in progress near Lunar Tycho Base Three turned up fragments of metal fabrications and structures. They looked like the ruins of some kind of installation. The more thorough probe that followed yielded no fewer than fourteen more bodies, or more accurately, bits of bodies from which at least fourteen individuals of both sexes could be identified. Clearly, none of the bodies was in anything approaching the condition of Charlie's. They had all been literally blown to pieces. The remains comprised little more than splinters of charred bone scattered among scorched tatters of space suits. Apart from suggesting that besides being physically the same as humans, the Lunarians had been every bit as accident-prone, these discoveries provided no new information—until the discovery of the wrist unit. About the size of a large cigarette pack, not including the wrist bracelet, the device carried on its upper face four windows that looked like miniature electronic displays. From their size and shape, the windows seemed to have been intended to display character data rather than pictures, and the device was thought to be a chronometer or a computing-calculating aid; maybe it was both—and other things besides.

  After a perfunctory examination at Tycho Three the unit had been shipped to Earth along with some other items. It eventually found its way to the Navcomms laboratories near Houston, where the gadgets from Charlie's backpack were being studied. After some preliminary experimenting the casing was safely removed, but detailed inspection of the complex molecular circuits inside revealed nothing particularly meaningful. Having no better ideas, the Navcomms engineers resorted to applying low voltages to random points to see what happened. Sure enough, when particular sequences of binary patterns were injected into one row of contacts, an assortment of Lunarian symbols appeared across the windows. This left nobody any the wiser until Hunt, who happened to be visiting the lab, recognized one sequence of the alphabetic sets as the months that appeared on the calendar. Hence, at least one of the functions performed by the wrist unit seemed closely related to the table in the diary. Whether or not this had anything to do with recording the passage of time remained to be seen, but at least odd things looked as if they were beginning to tie up.

  The linguistics section was making steady, if less spectacular, progress toward cracking the language. Many of the world's most prominent experts were getting involved, some choosing to move to Houston, while others worked via remote data links. As the first phase of their assault, they amassed volumes of statistics on word and character distributions and matchings, and produced reams of tables and charts that looked as meaningless to everybody else as the language itself. After that it was largely a matter of intuition and guessing games played on computer display screens. Every now and again somebody spotted a more meaningful pattern, which led to a better guess, which led to a still more meaningful pattern—and so on. They produced lists of words in categories believed to correspond to nouns, adjectives, verbs, and adverbs, and later on added adjectival and adverbial phrases—fairly basic requirements for any advanced inflecting language. They began to develop a feel for the rules for deriving variants, such as plurals and verb tenses, from common roots, and for the conventions that governed the formation of word sequences. An appreciation of the rudiments of Lunarian grammar was emerging from all this, and the experts in Linguistics faced the future with optimism, suddenly confident that they were approaching the point where they would begin attempting to match the first English equivalents to selected samples.

  The mathematics section, organized on lines similar to linguistics, was also finding things that were interesting. Part of the diary was made up of many pages of numeric and tabular material—suggesting, perhaps, a reference section of Useful Information. One of the pages was divided vertically, columns of numbers alternating with columns of words. A researcher noticed that one of the numbers, when converted to decimal, came out to 1836—the proton-electron mass ratio, a fundamental physical constant that would be the same anywhere in the Universe. It was suggested that the page might be a listing of equivalent Lunarian units of mass, similar to equivalence tables used for converting ounces to grams, grams to pounds . . . and so on. If so, they had stumbled on a complete record of the Lunarian system of measuring mass. The problem was that the whole supposition rested on the slender assumption that the figure 1836 did, in fact, denote the proton-electron mass ratio and was not merely a coincidental reference to something completely different. They needed a second source of information to check it against.

  When Hunt talked to the mathematicians one afternoon, he was surprised to learn that they were unaware that the chemists and anatomists in other departments had computed estimates of surface gravity. As soon as he mentioned the fact, everybody saw the significance at once. If the Lunarians had adopted the practice that was common on Earth—using the same units to express mass and weight on their own planet—then the numbers in the table gave Lunarian weights. Furthermore, there was available to them at least one object whose weight they could estimate accurately: Charlie himself. Thus, since they already had an estimate of surface gravity, they could easily approximate how much Charlie would have weighed in kilograms back home. Only one piece of information was missing for a solution to the whole problem: a factor to convert kilograms to Lunarian weight units. Then Hunt speculated that there could well be among Charlie's personal documents an identity card, a medical card—something that recorded his weight in his own units. If so, that one number would tell them all they needed to know. The discussion ended abruptly, with the head of the mathematics section departing in great haste and a state of considerable excitement to talk to the head of the linguistics section. Linguistics agreed to make a special note if anything like that turned up. So far nothing had.

  Another small group, tucked away in offices in the top of Navcomms HQ building, was working on what was perhaps the most exciting discovery to come out of the books so far. Twenty pages, right at the end of the second book, showed a series of maps. They were all drawn to an apparently small scale, each one depicting extensive areas of the world's surface—but the world so depicted bore no resemblance to Earth. Oceans, continents, rivers, lakes, islands, and most other geographical features were easily distinguishable, but in no way could they be reconciled with Earth's surface, even allowing for the passage of fifty thousand years—which would have made little difference anyway, aside from the size of the polar ice caps.

  Each map carried a rectangular grid of reference lines, similar to those of terrestrial latitude and longitude, with the lines spaced forty-eight units (decimal) apart. These numbers were presumed to denote units of Lunarian circular measure, since nobody could think of any other sensible way to dimension coordinates on the surface of a sphere. The fourth and seventh maps provided the key: the zero line of longitude to which all the other lines were referenced. The line to the east was tagged "528" and that to the west "48," showing that the full Lunarian circle was divided into 576 Lunarian degrees. The system was consistent with their duodecimal counting method and their convention of reading from right to left. The next step was to calculate the percentage of the planet's surface that each map represented and to fit them together to form the complete globe.

  Already, however, the general scheme was clear. The ice caps were far larger than those believed to have existed on Earth during the Pleistocene Ice Age, stretching in some places to within twenty (Earth) degrees of the equator. Most of the seas around t
he equatorial belt were completely locked in by coastlines and ice. An assortment of dots and symbols scattered across the land masses in the ice-free belt and, more thinly, over the ice sheets themselves, seemed to indicate towns and cities.

  When Hunt received an invitation to come up and have a look at the maps, the scientists working on them showed him the scales of distance that were printed at the edges. If they could only find some way of converting those numbers into miles, they would have the diameter of the planet. But nobody had told them about the tables the mathematics section thought might be mass-unit conversion factors. Maybe one of the other tables did the same thing for units of length and distance? If so, and if they could find a reference to Charlie's height among his papers, the simple process of measuring him would allow them to work out how many Earth meters there were in a Lunarian mile. Since they already had a figure for the planet's surface gravity, its mass and mean density should follow immediately."

  This was all very exciting, but all it proved was that a world had existed. It did not prove that Charlie and the Lunarians originated there. After all, the fact that a man carries a London street map in his pocket doesn't prove him to be a Londoner. So the work of relating numbers derived from physical measurements of Charlie's body to the numbers on the maps and in the tables could turn out to be based on a huge fallacy. If the diary came from the world shown on the maps but Charlie came from somewhere else, then the system of measurement deduced from the maps and tables in the diary might be a totally different system from the one used to record his personal characteristics in his papers, since the latter system would be the system used in the somewhere else, not in the world depicted on the maps. It all got very confusing.