The prey runs to the hunter

Numberless are the world's wonders, but none More wonderful than man; the stormgrey sea Yields to his prows, the huge crests bear him high The lion on the hill, the wild horse windy-maned, Resign to him; and his blunt yoke has broken The sultry shoulders of the mountain bull. Words also, and thought as rapid as air, He fashions to his good use...Sophocles, Antigone 

Since the dawn of history, man has speculated about the possibility that intel- ligent life may exist on other worlds beyond the Earth. This idea probably originated from the often unsuccessful attempts of primitive religions to give meaning to those aspects of the environment which had no simple explanations. In the ancient Vedda culture of Ceylon, the belief in the migration of the soul after death was linked with the concept of a plurality of habitable worlds. The dead souls were believed to migrate to the Sun, the Moon, and the stars before attaining the state of Nirvana. As astronomy developed, the concept of the existence of life on other worlds began to acquire some scientific bases. Most of the early Greek philosophers, both the materialists and the idealists, thought that our Earth was not the sole dwelling place of intelligent life. Considering the limitations of science at that time, these early philosophers displayed great originality and ingenuity. Thales of Miletus, the founder of the Ionian school of philosophy, taught that the stars and the Earth were made of the same material. Anaximander asserted that worlds are created and destroyed. Anaxagoras, one of the first proponents of the heliocentric theory, believed the moon to be inhabited. He also maintained that invisible "seeds of life," from which all living things originated, were dispersed throughout the universe. In later eras, similar concepts of "panspermia" (ubiquitous life) were propounded by various scientists and philosophers. This idea was incorporated into Christianity soon after its inception. The Epicurean school of materialist philosophy taught that many habitable worlds, similar to our Earth, existed in space. The Epicurean, Metrodoros, maintained: "To consider the Earth the only populated world in infinite space is as absurd as to assert that in an entire field sown with millet only one grain will grow." It is of interest that the proponents of this doctrine considered that not only the planets, but also other heavenly bodies in the vast reaches of space, were inhabited. The Roman philosopher, Titus Lucretius Carus, was an ardent exponent of the concept of the plurality of worlds. In his famous poem, On the Nature of Things, he wrote: "Nature is not unique to the visible world; we must have faith that in other regions of space there exist other earths, inhabited by other peoples and other animals." Curiously enough, Lucretius did not understand the true nature of the stars, but conceived of them as luminous terrestrial vapors; therefore, his inhabited worlds were located on the periphery of the visible universe. For fifteen hundred years after the birth of Jesus of Nazareth, Christian cosmology, influenced by the theories of Ptolemy, taught that the Earth was the center of the universe. The concept of life on other worlds seemed to be incompatible with this philosophy. The extrication of cosmology from the Ptolemaic system began when the gifted Polish astronomer, Nicolaus Copernicus, placed man in his proper position in the solar system, downgrading the status of Earth to that of one planet among the many revolving about the Sun.

"If God did not exist, man would be obliged to invent him." Said Voltaire

Are you so stupid as to think that just because we're alone here, there's nobody else in the room? Do you consider us so boring or so repulsive that of all the millions of beings, imaginary or otherwise, who are prowling around in space looking for a little company, there is not one who might possibly enjoy spending a moment with us? On the contrary, my dear—my house is full of guests . He possibility of life beyond the Earth evokes today strong and partisan emotions. There are some who want very much to believe that extraterrestrial life—particularly the intelligent variety—is common throughout the universe; and there are those who are committed to the view that extraterrestrial life is impossible, or so rare as to have neither practical nor philosophical interest. It seems to me appropriate that in this book more than passing attention be paid to such psychological predispositions. One spring some years ago, the Department of Astronomy received a tele- phone call from the local District Attorney's office. There was in progress the criminal trial of a gentleman whom I shall call Helmut Winckler, a Nebraskan who claimed to have had personal contacts with inhabitants of the planet Saturn. The state desired an expert witness. With wry comments and professional asides, the message was conveyed to me. I agreed to serve as a surprise witness for the prosecution and was presented with a sheaf of publications written by or about the defendant, concerning his extraordinary adventures. The following is my recollection of the statements made in these publications and subsequently verified by the defendant under oath: Winckler was a salesman of agricultural implements in Nebraska; he was of German ancestry, but born in the United States. He had few intellectual pretensions, but had at least a grammar school education. Winckler was a trifle chubby, of florid complexion and robust countenance, and wore steel-rimmed glasses. He looked considerably younger than his sixty-odd years, was soft-spoken and polite on the witness stand. His accent was that of the rural midwest. Winckler testified that one day while motoring along a back road in Nebraska, he had the remarkable good fortune to overtake a parked flying saucer. Naturally he stopped, as anyone would. To his surprise, he observed emerging from the saucer, several men and women of entirely human appearance, dressed in flowing robes and speaking mellifluously. The language which they were speaking so mellifluously was Hochdeutsch. Coincidentally, Winckler understood Hochdeutsch. The saucerians were delighted. Winckler was delighted. The saucerians explained that they were from the planet Saturn, and had, for reasons of their own, selected Winckler as an "intermediary." They were to impart to him information of great value for the inhabitants of the planet Earth. It seems that the international political situation on Earth had reached serious proportions, a fact which concerned the Saturnians, an old, wise, and sympathetic race. They were here to save us from ourselves. Winckler never revealed why he had been selected. It appears that it was not because he knew Hochdeutsch. The Saturnians speak all human tongues. In a universe whose size is beyond human imagining, where our world floats like a dust mote in the void of night, men have grown inconceivably lonely. We scan the time scale and the mechanisms of life itself for portents and signs of the invisible. As the only thinking mammals on the planet perhaps the only thinking animals in the entire sidereal universe—the burden of consciousness has grown heavy upon us. We watch the stars, but the signs are uncertain. We uncover the bones of the past and seek for our origins. There is a path there, but it appears to wander. The vagaries of the road may have a meaning, however; it is thus we torture ourselves. The size and structure of the universe what a wonderful and amazing Scheme have we here of the magnificent Vastness of the Universe! So many Suns, so many Earths. When, for the first time, we become aware of the vastness of our universe, we are awed and humbled. But if astronomers spent all their time speculating about the immensity of the cosmos and the prodigious intervals of time necessary for the evolution of the stars, their accomplishments would be few. The primary concerns of the astronomer when studying the cosmos are physical and mathematical interpretations of observations, predictions of future observations, and the development and refine- ment of his instruments for such interpretation and prediction. To help him in the conceptualization of his problem, the astronomer may, consciously or unconsciously, visualize a small model representing the cosmic system under investigation. Using this method, he can arrive at an understanding of the relative dimensions of the system and an understanding of the time intervals involved. I have spent a great deal of time in the study of the solar corona and the Galaxy. V The solar corona is an extended halo of glowing gas which surrounds the Sun and which can be seen during a solar eclipse. The Galaxy is a system of stars, called the Milky Way, in which our Sun resides. The Galaxy is surrounded by a halo of gas called the Galactic corona . The sizes of the solar and Galactic coronae are, of course, very different. I have always visualized each of them as irregular, approximately spherical bodies with somewhat the same dimensions—about 10 centimeters (4 inches) across. Why 10 centimeters? This figure is entirely arbitrary; it is convenient and easily visualized. I have sketched the outlines of the objects of my reflections in my notebook, attempting to preserve the apparent scales of the phenomena. 1 am, of course, quite aware that the dimensions of the Galactic corona are at least 100 billion times greater than those of the solar corona. However, I could ignore this fact, since the absolute size was not important for an understanding of the problem at hand. When the actual dimensions of an object are of special significance, I use formal mathematics. Until very recently the dimensions of the Earth were thought to be immense.