Martian Life: Canals on Mars Evidence of Past Glories

Prof. Percival Lowell is certain that the canals on Mars are artificial. And nobody can contradict him. —Clipping from unidentified newspaper (summer 1905)

Canals on Mars

On May 19, 1910, less than two months before his death, Schiaparelli publicly stated that natural forces could account for the dark lines seen on Mars. However, he went on to suggest that someone assemble all evidence related to the existence of intelligent life on the planet. In the concluding paragraphs of his final communication on Mars, Schiaparelli mentions his admiration for the work of Percival Lowell. This praise for Lowell raises doubts about Schiaparelli’s acceptance of a natural explanation of the canali. Lowell was an outspoken defender of canals built by Martians throughout his scientific career (1894– 1916). Percival Lowell (1855– 1916) was the most powerful champion within the scientific community for the idea of intelligent Martian life. His claim that the Martian landscape included a global irrigation system influenced the conception of Mars held by scientists, government officials, and the general public well into the second half of the twentieth century. Unlike Schiaparelli, Lowell wrote popular books and magazine articles and lectured widely on Martians as canal builders. Lowell was an energetic and effective publicist for his views on Martian life. Some writers have called Lowell a newcomer to astronomy, an outsider, and even an amateur. When Lowell began his scientific career, entrance into the profession did not require an advanced degree in astronomy. A number of distinguished early twentieth-century astronomers, including directors of major observatories, never received advanced training in astronomy. Lowell’s credentials as an astronomer were not unusual for his times. Lowell studied mathematics at Harvard University under America’s premier mathematician, Benjamin Peirce. Peirce fully expected his brilliant student to succeed him as a professor of mathematics. Lowell had different plans for the future. After spending a year abroad, and the next six years attending to the business holdings of his illustrious and wealthy family, Lowell left America to study the Far East. In 1882 Lowell had attended a lecture on Japanese culture by zoologist Edward S. Morse. Morse’s lecture inspired Lowell to travel to Asiatic countries recently opened to the West. The dark regions of the planet observed by astronomers were areas of vegetation, not bodies of water. The melting of the polar ice caps during the warm season freed water to flow through the canal system. The flowing water irrigated the desiccated planet and brought life to its vegetation. Lowell’s theory, completed after a short stay at Flagstaff, changed little over the next twenty years. In describing the orderly arrangement of the Martian canals, Lowell compared them to trigonometric figures. Lowell’s maps of the canals are simpler and more geometrical than Schiaparelli’s. There are two explanations for Lowell’s schematic maps. First, Lowell studied Mars using Schiaparelli’s maps as his guide. Second, according to Carl Sagan, Lowell was a poor draftsman who drew polygonal blocks linked by many straight lines. Pickering and Douglass were no better at rendering details of the Martian surface than Lowell.

Ancient Martian City?

The unique physical conditions of the planet, Lowell declared, explained the social behavior and technology of the intelligent creatures who lived there. Lowell claimed that because Mars was smaller than the Earth, it evolved faster. Mars continued on its rapid evolutionary path and soon reached the final stages of planetary development. Lowell believed that Mars was older than the Earth. All planets, Lowell argued, become drier as they age. At one time, the Earth had much more water than land. On Mars, land had largely replaced water, leaving the planet covered with vast desert regions of a reddish-ochre color. This color reminded Lowell of the Sahara region of northern Africa or the Painted Desert of Arizona. Mars was dry but not without water. Lowell drew attention to Martian polar caps that melted during the warm seasons. As the polar caps retreated, a deep blue band appeared around the poles. This band was ice that melted with the rising temperature of the Martian spring and summer. Lowell dismissed the hypothesis that the polar caps were largely frozen carbon dioxide, not snow and ice. A desert planet with water frozen in polar ice caps is an unlikely habitat for life. However, Lowell assured us that Mars had enough water to sustain life. It also had an adequate supply of air, another crucial ingredient of life. Lowell’s telescopic study of the disk of Mars convinced him, if not other astronomers, that Mars had an atmosphere. Water circulated throughout the atmosphere in a vaporous form and condensed at the poles of the planet. The freezing and melting of water at the polar caps convinced Lowell that the average temperature of Mars was comparable to the Earth’s, if not higher. Hence, Martian polar caps shrink back far more drastically during the warm seasons than do the ice caps at the Earth’s poles. The existence of water and air on Mars, along with its mild climate, were essential to Lowell’s picture of the planet as a place of constant change. It was not static like the airless, waterless, and lifeless Moon. Lowell first described the physical characteristics of Mars. Then he was ready to introduce life there. The Martian climate, smooth terrain, and adequate supply of water and air indicated life could thrive on the planet. If astronomers properly examined Mars through their telescopes, evidence of life would emerge.

Lowell claimed that the dark, bluish green regions of Mars turn to shades of gray and brown seasonally. The dark areas are plants that flourished with warmth and moisture and faded when the frosts of the Martian autumn arrived. The changing colors of Martian vegetation reminded Lowell of American forests seen from a distance.

Search for Alien Civilizations and the Age of the Universe

The age of the universe is known to be 12 to 15 billion years because, ever since the pioneering work of the American astronomers Vesto Slipher, Edwin Hubble, and Milton Humason in the first three decades of the twentieth century, the universe’s rate of expansion has been known. Measurements of galactic redshifts show that the farther away a galaxy is from us, the faster it recedes. In other words, redshift is proportional to distance. The data was collected by Hubble and Humason in 1931. Clearly, the relationship between distance and velocity of recession was a straight line. Therefore the equation representing this straight line is v = Hd, where v is the velocity of galactic recession, H is the slope of the line (now called the Hubble constant), and d is the distance between the observed galaxies and us. Velocity is expressed in kilometers per second, and d can be expressed in kilometers as well (although lightyears or megaparsecs— 1 megaparsec equals 3.26 million light-years— are more commonly used). Thus H, the Hubble constant, is expressed in kilometers times seconds 1 times kilometers 1 (or megaparsecs 1 ), which can be reduced to seconds 1 , which is of course the inverse of a time. Therefore the inverse of the Hubble constant, 1/H, gives the age of the universe in seconds— that is, the time elapsed between the Big Bang and now. Current estimates of the Hubble constant range between 50 and 100 km s 1 megaparsec 1 , with an apparent consensus at 80 km s 1 megaparsec 1 . The precise value of H is not known because of the difficulties and errors encountered when measuring galactic distances. The success our search for alien civilizations is intricately linked to an accurate perception of the age of the universe. Take the case of the early environment on a young earth. Earth’s atmosphere 4 billion years ago was very different from the one we know today. There was no oxygen, but other gases were present. In one scenario, these were methane (CH 4 ), water vapor (H 2 O), nitrogen (N 2 ), ammonia (NH3), hydrogen sulfide (H 2 S), and carbon dioxide (CO 2 ). Primeval hydrogen (H 2 ) and helium (He) were disappearing fast because Earth’s gravity was not strong enough to keep them in the atmosphere. Traces of helium would always be present, however, thanks to the radioactive decay of elements, such as uranium, thorium, and radium, in Earth’s interior. There were also oceans, whose geography we would not recognize today, since plate tectonics has moved the continents around. Volcanic activity contributed water, nitrogen, carbon dioxide, sulfur dioxide, and other gases to the atmosphere. 

All of the above planetary activities affect the formation of the primary information bearing organic compounds that serve as the blueprint of known life. A very interesting deduction from the study of earth's chemical evolution is that the primitive atmosphere might have been a reducing one. In a reducing environment, oxygen is absent. This was one of the motivations that led to what is known as the Miller's Experiment. Miller had set up his experiment in a flask with various water, methane, ammonia and hydrogen gases. He also induced electrical discharges in experiment to simulate lightening. After several days of cycling the gases and sparking, Miller noticed that the condensed water in the tube had turned pink and subsequently orange-red. Clearly, some chemistry was taking place, as the original gases were completely colorless. Analysis of the solution revealed the presence of amino acids, the building blocks of proteins! Of the twenty amino acids found in proteins, ten were formed in Miller’s experiments. The chemistry that took place in these experiments is now understood. For example, the simple amino acid glycine results from the condensation of formaldehyde (formed from the sparked gases) with ammonia and hydrogen cyanide (also formed in the gas mixture) to produce the compound aminonitrile. Aminonitrile then reacts with water to form glycine. In addition to amino acids that make up proteins, gas-discharge experiments have also yielded the four nitrogenous bases, adenine (A), cytosine (C), guanine (G), and uracil (U), the building blocks of RNA. Adenine for example, results from the condensation of five molecules of hydrogen cyanide (figure 4.3). (It is unsettling to think that the poison used to execute prisoners in a gas chamber can lead to the synthesis of some of the building blocks of life!) Finally, many types of sugars were also synthesized in these experiments, including ribose, the sugar found in RNA. The startling results of Miller’s experiments have led to the notion that Earth’s primitive oceans accumulated more and more of the building blocks of life, amino acids, nitrogenous bases, and sugars, and became some sort of primordial or prebiotic soup. (Instead of the term soup, which suggests a chunky mixture— think about split pea with ham or chicken noodle soup!—I prefer the word broth.) Primordial broths of the Miller type have been replicated by many investigators using similar gas mixtures exposed to short-wave UV light or silent electric discharge, all undoubtedly present on primitive Earth.

 Search for alien civilizations would be best served if focused on extrasolar planets that have been observed going through similar transformations. If the pattern of evolution of life on earth is truly universal, the process might have been replicated countless times across the cosmos that must have yielded intelligent life over time. An accurate realization of the age of the universe would give a quantitative indication of the multiplicity of the organic evolution on M-type planets and realistic odds of finding intelligent life one day.