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“life On Mars Is Almost Certain!”

July 2024
14min read

…And what’s more, the planet’s highly civilized inhabitants live together in perfect harmony. So argued an eminent astronomer named Percival Lowell, and for decades tens of thousands of Americans believed him.

EXPLORATION HAS A way of destroying as much knowledge and as many features as it reveals. At the first approach of an impartial observer, bodies of water have evaporated into thin air, navigable passages have healed up without a scar, and great lands firmly fixed on the map have sunk beneath the waves, carrying whole species of beings down with them. Exploration claimed new victims in the 1960s, when the Mariner space probes gave the world its first close view of the surface of the planet Mars. Hopes had run high. Ever since the 1890s, popular imagination, fueled by the work of the American astronomer Percival Lowell, had populated the red planet with an advanced race of beings. The Mariner pictures showed no such signs of civilization. The surface they revealed was barren, cratered, and, to all appearances, lifeless.

Lowell’s theory, to be sure, was not altogether original when it appeared. The belief in life on other worlds had a respectable American tradition, derived from a much older European one. During the Enlightenment the habitation of other planets was taken for granted. God, the master craftsman, would not have wasted matter building other worlds if He had not intended to populate them. On the same grounds Hugh Williamson, a scientist and signer of the Constitution, argued that comets, too, might carry intelligent life. In 1824 Eliphalet Nott, president of Union College, painted for his students a picture of extraterrestrial beings, “whose acuter vision or more powerful glasses enable them to look down on us, regardful of our progress … and impatiently waiting for the time when our improved instruments shall enable us to recognize their signals.” After the 1850s the belief began to wane, in part due to the influence of the English theologian and scientist William Whewell, who argued that man was clearly “uniquely favored among all God’s creatures.”

The seeds for a revival were sown in 1877, a year that brought Mars exceptionally near to Earth. Mars is best observed from Earth when it is in opposition—that is, when it and the Sun are on opposite sides of our planet. This occurs at intervals of slightly more than two years; the most favorable oppositions, when Mars is closest to Earth, occur approximately every fifteen years. The year 1877 brought one of the latter kind. In the United States, Asaph Hall took advantage of it to discover the two tiny moons of Mars, to which he gave the names Phobos and Deimos. In Italy the astronomer Giovanni Schiaparelli turned his attention to the surface of the red planet. Earlier observers had seen and mapped Martian features but none had seen what Schiaparelli now saw: a network of fine, often straight lines patterned across the surface. As they seemed to connect the dark areas (assumed at the time to be seas), Schiaparelli called them canali , Italian for “channels,” and gave them names from classical antiquity.

At the next two oppositions Schiaparelli saw more lines, some of them single, others seeming to be double channels. The initial response to his reports was one of skepticism. But soon some astronomers began to see the lines as well, though others did not and publicly doubted the channels’ existence.

The canali , which became known in English as “canals,” furnished grist for debate. The choice of “canals” rather than “channels” reflected the belief that the lines might be artificial in origin. While Schiaparelli himself refused to speculate, there were many who argued that such an ordered pattern could not have been produced naturally. A French astronomer, Camille Flammarion, did a great deal to popularize the idea of a vast Martian system of artificial waterways. The visible lines, he said, were not only the canals themselves but also the wide bands of vegetation being grown along their banks. Flammarion and his followers fixed a new idea of Mars in the public mind: a planet inhabited by an advanced civilization, wise and peaceful, prolonging existence and fending off the encroaching deserts by huge works of engineering.

The favorable opposition of 1892 was followed in two years by one almost as good. It was then that Percival Lowell entered the picture. Born in 1855 into the famous Boston family, Lowell had already completed two careers—one in business and one as a traveler and writer in the Far East—before returning to his old interest of astronomy. He left Japan in 1893 and came back to America, burning with eagerness to build an observatory and carry on the work begun by the aging Schiaparelli. When Mars began to reach opposition in the summer of 1894, Lowell made his first careful observations of the planet from his new facility, built in Flagstaff, Arizona Territory, to take advantage of the clear, dry air.

Lowell, gifted with keen eyesight (and, some said, with a lively imagination as well), had no trouble seeing the network of canali . During the summer and autumn of 1894 he began mapping and naming new lines, a project that would occupy him until his death in 1916. During that time the number of lines recorded would increase to more than seven hundred. Unlike Schiaparelli, Lowell did not confine himself to simple observation. Though he admired the Italian greatly, referring to him as the “Columbus of a new planetary world,” he believed that “as with Columbus, too, the full import of his great discovery lay hid even to him.” Convinced that the ordered pattern of the canals could only be the work of intelligent beings, Lowell made it his mission to carry this news to his fellow scientists and to the public.

Lowell gave a series of public lectures in Boston early in 1895, expounding his views on Martian life. He then wrote a series of four articles on the same topic for the Atlantic Monthly ; these articles, with additional material, appeared at the end of the year as a book titled Mars . As a biographer has noted, Lowell’s views underwent virtually no change over the years; the arguments given in Mars are not much different from those the astronomer would present in Mars and Its Canals (1906) or Mars as the Abode of Life (1908). Criticism from other scientists, which was abundant, failed to sway Lowell in the slightest.


His major argument stemmed from the pattern of the canal lines. Their regularity and straightness, so unlike what nature would produce, proclaimed the work of intelligent beings. Their purpose, irrigation, was indicated by the phenomenon of the “wave of darkening,” a change in color, which swept down along the canals from the poles toward the equator with the coming of spring. Lowell took this darkening to be the growth of crops watered by melting ice and snow from the polar caps. The orderly course of planetary evolution had made such an irrigation system necessary. Mars, being “older” than Earth, had lost its seas through evaporation (a point on which most astronomers agreed). A small amount of water remained, locked in the polar caps and released for use only during seasonal melting. An older planet would also have more highly developed inhabitants. Only such beings could have conceived and built the vast canal network, upon which their very survival depended in their parched world. “With them,” Lowell suggested, scientific instruments thought modern on Earth were “things of a bygone past, preserved with veneration in museums as relics of … the simple childhood of the race.”

Within the scientific community these speculations, won, at best, a chilly reception. While the Flagstaff observatory unquestionably turned out excellent work in other areas, from the start all its efforts tended to be eclipsed by the “Mars furor.” The polar caps, many astronomers alleged, were made of frozen carbon dioxide, not of the water essential to irrigation (a point vigorously disputed by Lowell). Others insisted that the atmosphere was too thin and the temperatures too low to support life (another point of bitter debate). The Englishman Alfred Russel Wallace, who, with Charles Darwin, had announced the theory of evolution in 1858, published an effective antiLowell book in 1907 called Is Mars Habitable? Raising many valid objections and some more dubious ones, Wallace sharply attacked the American astronomer’s “wholly unsupported speculation,” concluding that Mars “is absolutely UNINHABITABLE .”

The Harvard astronomer W. H. Pickering put forward a variety of alternative explanations for the canals. Pickering, who had been Lowell’s assistant at Flagstaff in 1894, soon emerged as his leading opponent in the popular press. In 1902 he wrote an article titled “The Canals in the Moon.” There were, said Pickering, observable bands of vegetation in craters on the lunar surface, resembling the Martian pattern; but surely no one would claim that they were the work of intelligent beings? Later he would suggest that the Martian canals were long cracks in the planet’s surface, lined with plant growth—or that the lines simply did not exist, save as chance markings organized into patterns by the eye of the viewer. This last idea soon became one of the main arguments against the canal theory.

Lowell found the coolness of other scientists annoying. He began to ascribe it to the vanity of the human race, to an unwillingness to admit the existence of superior beings in the universe. His opponents were like “Crusoe, who grows pale at the sight of footprints not his own.” Panic drove them to seize upon any alternative hypothesis, “no matter how improbable or even palpably absurd it be.” Nonsense, retorted Pickering. Astronomers would welcome “trustworthy evidence” of Martian life, “not only with pleasure, but with wild enthusiasm.”

Lowell remained skeptical. All his irritation went on public display in 1909 in an article he wrote for the Atlantic Monthly , “The Revelation of Evolution.” Ostensibly it is about Charles Darwin, whose centenary was observed that year. Yet at points the veil becomes embarrassingly thin, and the heroic portrait of the man “ahead of his time,” the lonely “pioneer in thought,” is obviously meant to apply to Lowell himself. Darwin was, as Lowell felt himself to be, the target of “that lower class of scientists who conceive science to be limited to the accumulation of facts,” and there is a touch of maudlin self-congratulation (“For a man to get the world’s ear while he is yet alive is his damning with faint praise”). And at the end, there is an unabashed appeal for support: “Let us be open-minded, and remember that the true regard is not to accept to-day what yesterday failed to appreciate, but to champion the advance that now is making while yet it is to-day.”

Popular support he did have, in abundance. Lowell was perhaps as dedicated and talented a popularizer of science—of his own theories, at least—as America has ever produced. He had, of course, the advantage of an inherently sensational topic. Lowell’s work was clearly among the influences that inspired H. G. Wells in the 1890s to write his chilling tale of Martian invasion, The War of the Worlds . Wells pictured a race of beings, hardened by life on a parched planet, setting out to conquer the lush, green earth. Readers of the day enjoyed the novel but preferred the picture given by Lowell and others of Mars inhabitants: a wise, serene, peaceful race that had long since done away with war.

Lowell was convinced that the regularity of the Martian canals proclaimed the work of intelligent beings.

For Lowell the evolutionist, as Mars was now, so Earth one day would be. “On our own world,” he mused, “we are able only to study our present and our past; in Mars we are able to glimpse, in some sort, our future.” This future held both good and bad. Mars prophesied a progressive drought. The belief that Earth’s deserts were spreading and its seas drying up won a good deal of support around the turn of the century. In 1904 the exiled Russian geographer and anarchist prince Peter Kropotkin forecast a long period of drought for Earth; early measures, he said, should be taken for combatting it. Lowell, of course, had the answer. Mars, like a good neighbor, was pointing the way: in all likelihood, irrigation canals would one day span a dry Earth from pole to pole. In time, the water would disappear altogether, and life with it. In Worcester, Massachusetts, a young man who had heard Lowell lecture and had read The War of the Worlds set himself a goal in life. Robert Goddard’s pioneering work in rocketry was planned to give mankind the means to save itself from extinction, by traveling to other worlds, as Wells’s Martians had done, when Earth was no longer habitable.

YET IF MARS SIGNALED catastrophe in the long run, its message for the short term was a cheering one. War, or even national boundaries, could not exist on the drought-stricken planet, for, as Lowell put it, “Isolated communities cannot there be sufficient unto themselves; they must combine to solidarity or perish.” Lowell enjoyed the paradox that the bloodred planet, named for the god of war, should point to a future of peace. “With Mars so peaceful,” he quipped in 1895, “Jupiter so young, and Venus so bashfully draped in cloud, the planets’ names accord but ill with their temperaments.” In the early twentieth century articles appeared in the popular press, explaining “Why the Dwellers on Mars Do Not Make War.” A poetic journalist, E.H. Clement, penned a verse epic on the pacifist lesson of Mars, concluding “So come new hopes and faith fresh from the stars/The Gospel sent us from the living Mars.”

In June of 1901 the Lowell Observatory had a visit from Lester Frank Ward, the leading figure in American sociology. He was invited to look at Mars through the large telescope. “I was surprised at what I could see,” he recorded. “I could see great canals or long cavities in various directions.” References to Martian life soon began to creep into Ward’s sociological papers. His enthusiasm is readily understood. Ward was leery of the popular Social Darwinism of the day. Lowell’s work confirmed his belief that man, like the Martians, could dominate and even conquer the natural environment instead of remaining the helpless plaything of it; furthermore, Mars showed that cooperation, rather than competition, was the way of the future.

In 1907 Ward wrote a popular article titled “Mars and Its Lesson.” By an involved series of geological comparisons, Ward decided that, although Mars was rapidly drying up, many millions of years would pass before Earth would reach that stage. On Mars we could see a “race of vast antiquity and supreme wisdom, clinging desperately to the orb that bore it, half gasping for breath, and hoarding every drop of its precious water, but doomed in the relatively near future.” This would be the fate of Earth, but in a future so distant as to be inconceivable. The prospects were bright indeed, and the “contrast with that old decadent orb that is now telling us its story, instead of depressing us, should inspire us with thankfulness that we are young, with faith in an unlimited future.”

Buoyed by the success of this article, Ward sketched out a full-length book on Mars to include chapters on biology, including plant and animal life, psychology, ethnology, and sociology, the latter divided between politics and culture. It is regrettable that it was never completed.

The nature of Martian society and, by extension, that of the future Earth was not a matter of general agreement. For Lowell it was a hierarchy of intellect, where “from top to bottom each individual has his place and fills it.… All are given a chance to rise, but only the worthy do.” James Cowan, in his novel Daybreak (1896), described an advanced Martian civilization animated by the principles of Christianity—Christ having been incarnated and crucified there (earlier than on Earth), as well as on every inhabited planet. Others, to the horror of the conservative astronomer, thought that socialism reigned on Mars. In 1920, at the height of the Red Scare, the novelist and editor William Dean Howells wrote a brief piece about an encounter with two visitors from the red planet—outspoken socialists both. A public meeting has been arranged. The Martians are advised: “Better confine yourselves to your material conditions—your canals and inland seas and polar snow-caps. Don’t touch on moral or economical affairs.” The visitors, heedless of the advice, describe Mars as it is, and are promptly deported—to Russia.

All such disputes, of course, could have been settled by establishing some communication with the beings on Mars. In 1901 Nikola Tesla, the brilliant, eccentric physicist, informed the world that he had received radio signals in his Colorado laboratory that had come, in all probability, from Mars. “The feeling is constantly growing on me,” said Tesla, “that I [have] been the first to hear the greeting of one planet to another.” Should neighborly feeling necessitate a reply, there would be “no insurmountable obstacle in constructing a machine capable of conveying a message to Mars.”


The idea of communication was revived in 1909. W. H. Pickering, still skeptical of Lowell’s theory, suggested a way to lay the whole matter to rest. Signals should be sent to Mars, on the assumption that advanced inhabitants—if there were any—would find a way of replying. Pickering suggested a system of mirrors, to flash light across the vast distance, at a cost he estimated at ten million dollars. Camille Flammarion thought it an excellent idea. “Martians,” he said, “were probably trying to communicate with the earth millions of years ago before our mammoth and cave men period.” Another astronomer suggested that the signal consist of a huge strip of black cloth, to be stretched out and rolled up at various points in a desert. Still another suggested radio waves.

In 1909 Lowell declared that new canals had appeared since he had begun observing Mars. The builders were still alive and at work; the system “is undergoing construction or adaptation at the present moment.” Yet in the years after the opposition of 1907 Lowell gave more of his attention than before to other topics—the search for a new planet (discovered in 1930 and named Pluto in honor of Lowell, because the symbol for Pluto combined Lowell’s initials) and an ambitious work on “planetology,” The Evolution of Worlds .


When Lowell died in 1916, the Martian canal theory did not die with him. In 1921 Guglielmo Marconi, the genius of electrical communication, announced, as Tesla had done, that he had received radio signals from the inhabitants of Mars. In 1924, at a very favorable opposition, there was a strong movement to have radio transmissions blacked out briefly so that the signals undoubtedly being beamed from the red planet could be detected. Even W. H. Pickering, so long a doubter, had begun to accept the possibility of a Martian civilization. A reporter titled his 1928 interview with the Harvard astronomer “Life on Mars Is Almost Certain!” Said Pickering, “Some [canals] are so straight and regular that we can explain them only as the result of intelligent design.” Furthermore, he and other observers had seen geometrical patterns on the Martian surface, from a cross within a circle to a five-pointed star, to which the same reasoning applied.

Yet the peaceful nature of the Martian beings was no longer taken so much for granted. One man can be held largely responsible. In February of 1912 the readers of Frank Munsey’s garish All-Story magazine opened the new issue to the first installment of a serial, “Under the Moons of Mars.” The by-line Norman Bean meant nothing to them. It was, in fact, a pseudonym (and a misspelled one at that), but even the author’s real name would have passed unnoticed. It belonged to an unsuccessful, middleaged businessman, Edgar Rice Burroughs. The future creator of Tarzan was breaking into the world of writing with an adventure novel set on a Mars whose landscape showed an obvious debt to Lowell.

The resemblance lies, though, entirely in the physical geography of Barsoom (as the beings on Burroughs’s Mars name their planet). The vast deserts and dry sea beds all bear witness to the desiccation which forced the inhabitants to their great feat of engineering. Capt. John Carter, mysteriously transported from post-Civil War America to Barsoom, finds the so-called Martian canals to be water-ways lined by wide ribbons of irrigated land stretching from pole to pole.

Lowell’s theory did not die with him; only with the three Mariner probes were speculations finally laid to rest.

The social structure of this planet could not be more different from that postulated by Lowell or Ward. Only one Martian in a thousand, Carter finds, dies a natural death. The social and racial integration Ward had ascribed to Mars is lacking, for there are several distinct groups: the red Martians, the most advanced and noble; the violent, treacherous green men; and yellow and black races as well, all incessantly at war.

BURROUGHS WROTE numerous sequels, which became much wilder in plot and imagination, but he maintained that his portrait of Mars was faithful to the spirit of life on the red planet. In the mid-1920s he informed a newspaper that the Martians were “nomadic, war-like, predatory.” “The constant battle for survival,” he continued, “has rendered the Martian merciless almost to cruelty.”

In later years such headlines as “Farewell to Martians,” announcing new discoveries at odds with Lowell’s beliefs, appeared regularly. Nevertheless, in the popular mind, and in the minds of some astronomers as well, the canal theory remained something to be taken seriously, and every close opposition brought a new rash of speculation.

The three unmanned Mariner probes of 1965, 1969, and 1971, flying past and around Mars, sent back pictures that finally demolished the Lowell theory and, at the same time, forced scientists to change much of their thinking about the planet. The surface revealed by the Mariner probes and by the later Viking landings on Mars was indeed dry, but there was no sign to the cameras of intelligent beings or of an irrigation network—or even of vegetation. And certainly the surface was not what Lowell and Ward had proclaimed it to be: smooth and flat, with all irregularities worn or carved away by technologically advanced inhabitants. Instead there were craters, enormous canyons, and huge meandering depressions resembling dry riverbeds probably produced long ago by freely running water. It is remotely conceivable that some basic form of life does exist on Mars, as yet undetected; but the search for intelligent beings has moved on to other frontiers (though unhampered today by the old assumption that conditions must be Earthlike for life to exist).

It is difficult today to understand how so much speculation could be generated by a geometric pattern of lines seen at a distance of millions of miles. Like a Rorschach blot, the canals called forth from each observer the visions fitting his beliefs: Lowell’s intellectual hierarchy, Ward’s social Utopia, Howells’s socialists, Cowan’s Christians, and Burroughs’s vivid warriors all owe as much to the writer’s personality as to anything seen through a telescope. It was generally agreed that the Martians were of a higher order than we are; hence each person’s vision of the ideal, often of himself, became his vision of the Martian. In the sixth century B.C. , Xenophanes observed that men picture gods in their own image, but that if horses had hands, they would draw gods who looked like horses.

Nonetheless, it was the most generally appealing of these personal views that would be embraced by the public in general. In the years before World War I this was undoubtedly the one offered by Lowell himself. It was comforting to look at Mars and read there the progress of man, moving away from war, toward cooperation. The enthusiasm people felt for Lowell’s work in the early 1900s is not difficult to understand. Years before Lincoln Steffens, they had seen the future, and it worked.

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