TO the earliest stargazers, the planet Mars was a fearful omen suspended in the sky. The Babylonians took its strange reddish hue as a warning of bloodshed and fire, and the ancient Syrians sought to ward off such evils with human sacrifices. The Greeks, who called it Ares, and the Romans, to whom it was Mars, both regarded it as the god of war. To this day, the martial shield and spear remain the symbol for the red planet.
Modern science has long since dispelled most of the ancient myths. Yet it has failed to solve one of the great Martian mysteries: Does the planet harbor any form of life?
The idea that there might be intelligent life on Mars took root in the 17th century, after Johannes Kepler developed his theory of planetary motion, which helped rebut the old Ptolemaic idea of an earth-centered system of celestial bodies. Kepler’s ideas supported the Copernican theory that the sun is the true center of man’s universe. Its implications were profound. If the earth is only one of several planets orbiting the sun, could it be the only one to contain life? Newton, Huygens and Voltaire all speculated on the existence of intelligent life elsewhere in the solar system, even on the sun itself. The 18th century astronomer, Johann Elert Bode, author of Bode’s Law (each planet is roughly twice as far from the sun as the previous one), insisted that spiritual values increased similarly with the distance from the sun. That would make Martians considerably more spiritual than earthlings.
Tapping the Icecaps
As scientific techniques improved, astronomers saw enough to become increasingly convinced that most planets were inhospitable to life. Yet Mars continued to provoke serious speculation, largely because it showed so many characteristics that seemed fascinatingly similar to those of earth. The red planet turned out to have an atmosphere, albeit an extremely thin one. The tilt of its axis (about 24°) is approximately the same as the earth’s, thus creating seasonal changes. Its huge white polar caps suggest the presence of ice, and therefore water—a prerequisite for life as human beings know it. It also has large dark areas that grow, like earthly vegetation, in spring and recede in autumn.
In 1877, the Italian astronomer Giovanni Virginio Schiaparelli (an uncle of the present-day Paris couturier) reported mysterious lines, or canali, linking those dark areas. By 1906, Percival Lowell, an amateur astronomer and one of the Boston Lowells (his brother Abbott Lawrence was president of Harvard, his sister was Poet Amy), had plotted more than 700 canals at his Mars observatory in Arizona. He believed that the canals had been built by an advanced civilization desperately trying to tap moisture from polar ice to conserve its dwindling water supply.
Phobos and Deimos
No matter how hard they have looked, many other astronomers have been unable to locate Lowell’s canals. Most likely, says Franklin A. Gifford Jr. of the U.S. Weather Bureau, Lowell spotted elongated sand dunes that resemble canals from afar; a dune of this sort in Libya extends more than 400 miles and is three miles wide.
Arguments over the possibility of advanced intelligence on Mars are dying slowly. Only a decade ago, a Soviet astronomer suggested quite seriously that Mars’ two tiny moons, Phobos and Deimos (Fear and Terror, named after the two attendants of the ancient god of war), might be artificial satellites sent into orbit by Martians. But they would have to be unlike any terrestrial creatures. More than ever, Mars seems hostile to most earthly forms of life. Its surface appears exceptionally dry; its atmosphere seems to be composed largely of carbon dioxide with only a trace of water vapor.
In simulated tests on earth, however, such lowly forms of life as bacteria have survived in a Marslike environment. Moreover, some biologists theorize, life could have evolved on Mars by entirely unfamiliar biological processes. That does not mean that scientists expect to find strange, advanced beings on Mars. But they do not preclude the possibility of primitive life unlike anything ever seen on earth.
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