Excitement ran high in the world's observatories in 1877. That year, the mysterious red planet Mars came unusually near the earth, permitting astronomers to view it at close range and make two important discoveries. The first discovery—that the planet had two tiny moons stirred intense interest among scientists, but the second captured the imagination of people everywhere and provoked controversy and speculation that still go on today. From Milan, Italy, Giovanni Schiaparelli announced to the world that through his powerful telescope he could see peculiar dark lines crossing the surface of the planet in all directions, and to him they looked like canals.
Astronomers had been studying Mars through telescopes since the days of Galileo, in the seventeenth century, but none had been able to observe "canals" that might imply the existence of life on the planet. Schiaparelli himself was very cautious not to draw any firm conclusions, but one noted scientist of his day wrote with conviction: "It is no longer permissible to doubt that the planet Mars is inhabited by a race of intelligent beings... that these beings execute works; that they possess, in consequence, industrial means; that they know science, the arts, and also astronomy."
The discovery of the mysterious lines on Mars sparked new interest in the planet and the building of new and improved observatories. In Flagstaff, Arizona the renowned astronomer Percival Lowell set up the now famous Lowell Observatory. The location was chosen for its unusually clear sky, and today the observatory is one of the best equipped in the world. In 1894, when Mars again orbited closer to the earth than its usual distance, Lowell made an intensive study of the planet and was able to sketch more than four hundred different canals. As far as he was concerned, they were irrigation canals, built by Martian inhabitants to carry water from the melting polar snowcaps to the desert regions near the equator.
The famous French astronomer Camille Flammarion had another idea. He maintained the lines showed cultivation along the banks, not the canals themselves, but this also argued for the existence of life on Mars.
Still, there were many astronomers who dismissed such ideas. Some said the lines were not lines at all, but stretches of land irregularities blending together. Others, while agreeing that the lines were solid, did not feel they necessarily meant the presence of intelligent life. Father Moreux, director of the Observatory of Bourges in France, declared: "Nature offers examples of nearly perfect geometric forms ... the study of crystals, cells and tissues will enlighten you on that point."
The mathematician Alan Webb argued otherwise. To distinguish between a network traced at random, as in a cracked vase, and one deliberately laid out, Webb devised a mathematical criterion, and according to it the Martian canals appeared to be intentionally designed.
Science fiction writers had a field day with the stimulating idea that life might exist on Mars, and for a while books and magazines by the hundreds speculated on the nature of the planet's inhabitants and the possibility of their invading the earth with strange ships and weapons. Probably the most famous such story was The War of the Worlds, written by H. G. Wells in 1898, in which Martians landed in space ships and began to conquer the world with huge robots. Mankind was saved only because the invaders proved susceptible to the world's lowest form of life—the common germ. In 1939 the story was made into a realistic radio program, causing panic among many listeners who became convinced they were hearing the sensational news of an actual Martian invasion. Although the program was clearly identified as a fictional radio play when it began, people who tuned in late heard only the voice of a terror-stricken newscaster giving an eyewitness account of Martian monsters destroying everything in their path as they advanced on New York City.
Mars has been an object of fascination ever since man first studied the heavens. The ancient Greeks wondered much about the stars and planets and believed they revolved around the earth. This interest in the planets led to astrology, still practiced by those who believe the planets have personalities and control man's destiny.
Mars, for instance, was the Roman god of war, which would seem appropriate in view of what astronomers have discovered about the planet. It is reddish—the color associated with blood and energy—and its surface appears to be a wasteland swept by icy winds and clouds of dust.
In Roman mythology, Mars was the father of Romulus and Remus, the legendary twins who were raised by a she-wolf. Romulus was considered the founder of Rome and Mars its protector. The two horses which pulled Mars' chariot were Deimos and Phobos (Dread and Fear), and these names were given to the planet's two moons after they were discovered by Asaph Hall at the Naval Observatory in Washington in 1877.
Although the planet Mars has been an object of interest since ancient times, its size, appearance, and distance from the earth were not known until the telescope was invented. To the telescope has since been added the spectroscope, a device that separates a ray of light into its different colors for study of the light source. To these two instruments astronomers owe most of the knowledge they have of Mars.
Mars is about 4,200 miles in diameter, inclined on its axis, and its period of rotation is about 25 hours. In these respects it is not too different from the earth. The Martian year is 687 days, about twice the earth's, and since the planet is around 140 million miles from the sun it is much cooler than the earth, which is around 93 million miles. Its two moons are very small, only about ten miles in diameter.
It is known that Mars has an atmosphere because clouds can be seen, but its air is very thin and mostly carbon dioxide. Without oxygen, animal life as we know it cannot exist. Plant life, on the other hand, needs carbon dioxide. Mars has white polar caps, which are thought to be snow since they expand during the planet's cold season and shrink during the warmer periods.
Temperatures on Mars range from a low of about minus 70 degrees F. at the poles to nearly 50 degrees at the equator, which is chilly by earth standards but adequate to support some forms of plant life even in the colder regions. On earth, moss and lichens are found even on the icy peaks of our highest mountains. Recently some scientists collected moss and lichens from Mount McKinley, the Painted Desert and the Grand Canyon. They put the plants in glass jars and replaced the air with low-pressure "Martian air," then heated and cooled the containers to approximate conditions on Mars. The plants continued to thrive.
It is fairly certain that plants can live on Mars, and since plants produce oxygen it is possible there may also be some forms of simple animal life. Some scientists believe that Mars once was able to support even human life. The reddish color of the planet is thought to be iron oxide—rust—which could have been produced in some remote past when oxygen and water were plentiful. And this possibility leads to the interesting speculation that Mars once may have had inhabitants who perished when the planet's supply of water and oxygen was exhausted. Some writers have even suggested that the Martians foresaw this, and built subterranean cities engineered for comfortable atmosphere, humidity and temperature, where they live to this day manufacturing their air from the oxygen-rich soil. A Russian astrophysicist, Chklowski, maintains that the planet's moons are actually artificial satellites launched long ago by highly intelligent beings.
Man may not have to wait much longer to learn the answers to many of the red planet's mysteries. Space probes launched from earth will soon be radioing back data, perhaps even pictures, that may tell us about the strange markings called canals. From what we know of the planet now it seems too much to hope that any inhabitants will be found. But as Schiaparelli said when the same thing was suggested in 1877, "I am very careful not to combat this supposition, which includes nothing impossible ...."