From the Earth to the Moon (6 page)

A
N OBSERVER
endowed with infinitely penetrating vision, and placed at the unknown center around which the world gravitates, would have seen myriads of atoms filling space during the chaotic period of the universe. But gradually, as the centuries passed, a change took place; a law of attraction manifested itself and was obeyed by the atoms that had hitherto been wandering; they combined chemically, according to their affinities, grouped themselves into molecules and formed those nebulous masses which are strewn throughout the depths of space.

Each one of these masses soon acquired a movement of rotation around its central point. This center, composed of sparse molecules, began spinning and progressively condensing. In accordance with the immutable laws of mechanics, as its volume was diminished by condensation, its rotary motion was accelerated. From the continuation of these two effects there resulted a principal star, the center of the nebulous mass.

If he had watched attentively, the observer would then have seen other molecules in the mass behaving like the central star: condensing in a constantly accelerating rotary motion as it had done, and gravitating around it in the form of countless stars. A nebula had
been formed. Astronomers now count nearly five thousand of them.

Among these five thousand nebulae there is one which men have named the Milky Way. It contains eighteen million stars, each one of which has become the center of a solar world.

If the observer had particularly examined one of the smallest
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and brightest of those eighteen million stars, the one we proudly call the sun, all the phenomena to which the formation of the universe is due would have taken place before his eyes.

He would have seen the sun, still in a gaseous state and composed of loose molecules, turning on its axis to complete its work of concentration. This motion, faithful to the laws of mechanics, accelerated as the sun’s volume decreased, and finally the time came when centrifugal force prevailed over centripetal force, which tends to push molecules toward the center.

Then another phenomenon would have taken place before the observer’s eyes. Molecules located in the plane of the equator, escaping like a stone from a sling whose cord has just snapped, formed several concentric rings around the sun, like those of Saturn. These rings of cosmic matter rotated around the central mass, then began disintegrating and breaking up into secondary masses, i.e., into planets.

If the observer had watched these planets he would have seen them acting exactly like the sun and giving birth to one or more cosmic rings. This was the origin of those minor bodies known as satellites.

Thus, in going from the atom to the molecule, from the
molecule to the nebulous mass, from the nebulous mass to the nebula, from the nebula to the principal star, from the principal star to the sun, from the sun to the planet, and from the planet to the satellite, we have the whole series of transformations undergone by heavenly bodies since the first days of the world.

The sun seems lost in the immensities of the stellar world, and yet current scientific theory tells us that it is part of the Milky Way. It is the center of a world, and, however small it may seem in the vast reaches of space, it is actually enormous, for its size is 1,400,000 times greater than that of the earth. Around it gravitate the eight planets that came from its entrails at the beginning of creation. In order of nearness to the sun, they are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. In addition, moving in regular orbits between Mars and Jupiter, there are smaller bodies which may be the debris of a larger body broken into thousands of pieces. The telescope has revealed ninety-seven of them so far.
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Some of these attendants of the sun, held in their elliptical orbits by the great law of gravitation, have their own satellites. Uranus and Saturn have eight each, Jupiter has four, Neptune may have three, the earth has one. The latter, one of the smallest in the solar system, is called the moon, and it was the objective that the bold American spirit had set out to conquer.

Because of its relative nearness and the rapidly changing spectacle of its various phases, the moon shared man’s attention with the sun from the very beginning. But
the sun is tiring to the eyes, and the splendor of its light soon forces those who look at it to avert their gaze.

Pale Phoebe, however, is more humane; she graciously lets herself be seen in all her modest charm; she is unassuming and gentle to the eye, and yet she sometimes takes the liberty of eclipsing her brother, the radiant Apollo, without ever being eclipsed by him. Realizing the debt of gratitude they owed to this faithful friend of the earth, the Mohammedans established their month in accordance with her revolution.
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The ancient nations worshiped that chaste goddess. The Egyptians called her Isis, the Phoenicians Astarte; the Greeks worshiped her under the name of Phoebe, daughter of Leto and Zeus, and they explained her eclipses by her mysterious visits to the handsome Endymion. Mythology tells us that the Nemean lion roamed the moon before appearing on earth, and the poet Agesianax, quoted by Plutarch, celebrated in his verses the gentle eyes, charming nose, and gracious mouth formed by the bright parts of the adorable Selene.

Although the ancients had a good understanding of the character, temperament, and general moral qualities of the moon from a mythological point of view, even the most learned of them were extremely ignorant of its physical nature.

Some ancient astronomers, however, discovered certain things about the moon that have been confirmed by modern science. While the Arcadians claimed to have lived on the earth at a time when the moon did not yet exist, while Tatius regarded it as a fragment of the sun, while Aristotle’s disciple Clearchus held it to be a smooth mirror in which images of the ocean were reflected, and
while others saw it only as a mass of vapor given off by the earth or a revolving globe that was half fire and half ice, a few learned men, by means of shrewd observations, lacking optical instruments, surmised most of the laws that govern it.

Thus Thales of Miletus, five hundred years before the birth of Christ, voiced the opinion that the moon was illuminated by the sun. Aristarchus of Samos gave the correct explanation of its phases. Cleomedes taught that it shone with reflected light. The Chaldean Berosus discovered that the duration of its rotation was equal to that of its revolution, and in this way he was able to explain the fact that it always presents the same side to the earth. Finally Hipparchus, nearly two centuries before Christ, recognized certain irregularities in its apparent motions.

These various observations were later confirmed, and were beneficial to later astronomers. Ptolemy in the second century, and the Arab Abul Wefa in the tenth, completed Hipparchus’ discoveries concerning the irregularities of the moon’s motion as it describes the undulating line of its orbit under the influence of the sun. Then Copernicus in the fifteenth century, and Tycho Brahe in the sixteenth, completely described the solar system and the part played by the moon in the assemblage of heavenly bodies.

At that time its motions were determined more or less accurately, but little was known of its physical constitution. Then Galileo explained the light phenomena that occurred at certain phases of the moon by the existence of mountains on its surface. He placed their average height at 27,000 feet.

Hevelius, a Danzig astronomer, later lowered the greatest heights to 15,600 feet, but his colleague Riccioli brought them up to 42,000.

At the end of the eighteenth century, Herschel, armed with a powerful telescope, drastically reduced the previous measurements. He gave 11,400 feet to the highest mountains and brought the average to only 2,400. But he, too, was mistaken. It took the observations of Schroeter, Louville, Halley, Nasmyth, Bianchini, Pastorf, Lohrmann, and Gruithuysen, and especially the patient studies of Beer and Moedeler, to settle the matter definitively. Thanks to these scientists, the height of the mountains of the moon is now perfectly known. Beer and Moedeler measured 1,905 mountains, of which six are greater than 15,600 in height, and twenty-two are higher than 14,400 feet.
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The tallest peak rises 22,806 feet above the surface of the moon.

At the same time, visual exploration of the moon was being completed. It was seen to be riddled with craters, and its essentially volcanic nature became increasingly apparent with each observation. From the absence of refraction in the light from planets occulted by it, the conclusion was drawn that it must have almost no atmosphere. This lack of atmosphere implied a lack of water. It was therefore obvious that, to live under such conditions, the lunar inhabitants must have a special constitution and be radically different from the inhabitants of the earth.

Finally, thanks to new methods, improved instruments constantly scanned the moon, leaving no part of its visible surface unexplored, even though its diameter is 2,150 miles, about a quarter of the earth’s, its area is one-thirteenth that of the earth, and its volume one-forty-ninth. None of these secrets could escape the eyes of the
astronomers, and the skilled scientists carried their prodigious observations still further.

Thus they noticed that when the moon was full there were white lines across it, and black lines during its phases. They studied these lines with greater precision and succeeded in determining their nature. They were long, narrow furrows with parallel edges, usually ending in the vicinity of a crater, about fifty feet wide and anywhere from ten to a hundred miles long. The astronomers called them “grooves,” but giving them that name was all they could do. As for the question of whether or not these grooves were the dry beds of former streams, they could not answer it satisfactorily. The Americans hoped to be able to solve this geological puzzle some day. They also intended to reconnoiter that series of parallel ramparts discovered on the surface of the moon by Gruithuysen, a learned Munich professor, who regarded them as a system of fortifications erected by lunar engineers. These two obscure points, and no doubt many others, could not be definitely settled until there had been direct communication with the moon.

There was nothing more to be known with regard to the intensity of its light: the scientists knew that it is three hundred thousand times weaker than that of the sun, and that its heat has no appreciable effect on a thermometer. As for the phenomenon known as “ashy light,” it is explained by the effect of sunlight reflected from the earth to the moon, which seems to complete the lunar disk when it is seen in the shape of a crescent during its first and last phases.

Such was the state of acquired knowledge concerning the earth’s satellite. The Gun Club proposed to augment it from every point of view: cosmographic, geological, political, and moral.

O
NE IMMEDIATE
effect of Barbicane’s proposal was to focus attention on all astronomical facts relating to the moon. Everyone had been studying it assiduously. It seemed that the moon had appeared on the horizon for the first time, that no one had ever seen it in the sky before. It became fashionable; it was the celebrity of the day without seeming less modest, and took its place among the “stars” without showing any more pride. The newspapers revived old stories in which the “wolves’ sun” played a part; they recalled the influence that the ignorance of earlier times had attributed to it, they sang its praises in every way; they stopped just short of quoting its witty remarks. The whole country had a case of “moon fever.”

The scientific journals dealt more specifically with matters concerning the Gun Club’s project. They published the letter from the Cambridge Observatory, commented on it, and gave it their unqualified approval.

In short, it was no longer permissible for even the least learned American to be ignorant of a single one of the known facts about the moon, or for even the most narrow-minded old woman to go on entertaining superstitious
beliefs about it. Science came to them in every form and penetrated through their eyes and ears. It was no longer possible to be an ignoramus—in astronomy.

Till then, many people did not know how the distance from the earth to the moon had been measured. Experts took the opportunity to tell them that it had been measured by means of the moon’s parallax. If the word “parallax” seemed to surprise them, they were told that it was the angle formed by two straight lines projected to the moon from opposite ends of the earth’s radius. If they doubted the accuracy of this method, it was immediately proven to them that not only was this average distance 234,347 miles, but that the astronomers’ error was less than seventy miles.