Exploration of Mars
Without both expert scientists and interested amateurs to follow up on preliminary experiments, much of our common knowledge science would not even be possible. Likewise, without these very same innovators we would not have the subjective, human side of science that helps promote further argument and investigation. One example is the case of the discovery and exploration of Mars. Mars is an example of how many different biases and ideas form our perception and practice of science, as well as how technology helps break through the limitations of human subjectivity.
Though observation of Mars can be traced back to ancient Greece and Babylonia, it is better to start with a more advanced era of scientific discovery. This era of Mars observation started with the reintroduction of the heliocentric theory by Nicolas Copernicus in the early 16th century. Like his predecessor, Aristarchus, the Catholic Church and other scientists of the era criticized his ideas. These criticisms forced Copernicus to amend his theory more toward the laborious idea of a group of smaller orbits (epicycles) rotating in one larger circle (deferent). The theory came under extreme criticism from Tyco Brahe, a late 16th century observer of Mars.
Brahe’s observational skills were nearly as well known as his personal life and habits. Despite his flamboyant personaly, King Frederick the Second of Denmark allowed him the use of an island belonging to the Danish for scientific purposes. Starting in 1576, Brahe moved into Hven and established an observatory. He was a proponent of the geocentric theory, but his main achievements in the discovery of Mars would be his observations. One of Brahe’s assistants, Johannes Kepler, would take his position after Brahe’s death in 1601. Kepler was ideologically different to his mentor and would use Brahe’s observations to help prove his ideas on the solar system. Kepler’s use of his mentor’s exact observations helped him conclude several things.
First, the orbit of Mars was determined to be elliptical, very different from the accepted idea of perfectly circular orbits accepted by many at the time. Second, Kepler used the actual positions to figure out the path of Mars. This meant using the actual position of the Sun instead of an artificial point in order to determine the true orbit of Mars and true inclination of that orbit. Third, Kepler observed that Mars came closer to the Earth than the Sun did, proving to be more true to the Copernican theory than to the Tyconian theory. All of these new ideas blew apart traditional ideas of the space beyond Earth and would help move the observation of Mars into new territory.
The next stage in Mars observation moved beyond where Mars was going and moved toward answering the question of what Mars was exactly. Galileo Galilei started observing the phases of Mars in 1610 with very crude observational equipment, though at the time it was top of the line. In 1636, Francesco Fontana was the first to use a telescope designed specifically for astronomy and observed the actual face of Mars. Following his observations, Fontana drew a crude map, one of the first of its kind. The Dutch scientist Christiaan Huygens did observed Mars in the year 1659. Using a newly refined telescope, Huygens discovered the rotational period of the planet by observing spots on the planet and how many times they appeared.
He also noticed what looked like polar caps on Mars, similar to those of Earth and later a topic of debate amongst scientists. In the 1780s, William Herschel continued observations of Mars with very sophisticated telescopes and confirmed the existence of polar ice caps. He also noted a reduction in the size of the caps, spurring the idea of seasonal change similar to Earth. Herschel also measured the diameter of Mars to be 0.55x that of Earth, a figure that would be contested later by Johann Schroeter in 1787. The measurements of Mars would change incrementally until the first push of exploration in the 20th century. The red planet would move into an era of fantasy and illusion in the 1860s.
This era of Mars as a “second Earth” would start with a miscommunication of terminology from Pietro Angelo Secchi to English speaking astronomers. An Italian scientists, Secchi first coined the usage of the term “canali” in order to refer to the dark lines on Mars. In Italian, this word refers to natural waterways but this meaning was lost in the translation into the English word “canals.” The English word refers to artificially built waterways, promoting the idea of possible intelligent life on Mars. Giovanni Schiaparelli mapped these “canals” extensively in 1877. He was determined to create a new and accurate map of Mars. Schiaparelli changed the nomenclature of Mars’ land bodies, changing confusing language into a combination of biblical and classical references (example: Column of Hercules).
This drew on the emotions of the public and further developed myths about the planet. Schiaparelli was positive of the existence of canals, stating: “It is as impossible to doubt their (canali) existence as that of the Rhine on the surface of the Earth.” This statement and what it represented drew the ire of a great many scientists. One specifically was Nathaniel Green, who saw the “canals” as indefinite dark spots and not the sharp lines drawn by Schiaparelli. The problem wasn’t with what was observed necessarily but what was recorded. However, the idea of canals and intelligent life fascinated the public, promising further research into the possibility of life on Mars.
Percival Lowell would be the successor to Schiaparelli’s ideas when he established the Lowell Observatory in Flagstaff, Arizona, in the late 19th century. Lowell not only believed there were canals on Mars but that they were connected as an intricate system developed by a dying society on the planet. His book about Mars, Mars and Its Canals, in 1896, was the culmination of Lowell’s ideas and observations of Mars. Like Schiaparelli, Lowell drew a backlash from the mainstream scientific community. Alfred Russel Wallace, the co-discoverer of the theory of evolution, wrote a counter argument called Is Mars Habitable? This book pointed out the fallacies in Lowell’s theories, not necessarily what he saw. In 1913, E. Walter Maunder performed an experiment on visual perception in relation to the Martian channels. He put a group of children at different distances from a picture of a series of dots.
The kids closest to the painting drew the dots because they could see the dots clearly. The kids furthest away could not discern the dots to be anything and drew nothing. But, the children in the middle drew the dots as dark, definitive lines because the dots appeared as such. This experiment was meant to prove why the canals were observed as they were, but was largely rejected by the scientific community. Even without the solid support of mainstream science, canals, and the possibility of life were kept alive because of the myth and fantasy so craved by the public. These hopes and dreams were crushed in the mid-20th century with very refined observations and the beginnings of exploration.
In the 1940s and 1950s, photography and advanced telescopes started to break at the foundation for the argument of intelligent life. First, very refined pictures of the planet helped prove that canals did not exist but the dark lines seen by earlier scientists were merely the effects of dust and winds. In the 1940s, spectrographers used Doppler theory to determine what elements composed Mars’ atmosphere. In 1947, Gerald Kuiper determined what the atmosphere was predominantly carbon dioxide, which further hurt the theory of Mars as an Earth-like planet. Fifteen years later, the Russian space program moved toward reaching Mars with its first interplanetary satellites, Mars 1 and 2. Both of these satellites failed to reach their intended destination, suffering rom mechanical failure before orbiting Mars. Several American satellites and the Russian Zond 2 were launched but all failed to get near Mars.
The first successful Mars orbiting satellite was the American Mariner 4 satellite in July 1965. The satellite took 22 TV images of the surface of Mars from Martian orbit. These photos, the first of their kind, shocked the scientists involved and reshaped the image of Mars. Instead of a planet of canals and rich vegetation, Mars was a desert of red rocks, dunes, and craters with no signs of life. The measurements of the satellite also changed the view of Mars from the public. The atmosphere consisted mainly of carbon dioxide and had very low atmospheric pressure. Both of these factors nearly destroyed the possibility of vegetation or life on the planet. The following missions of Mariner 6 and 7 in 1969 further disappointed the public, not providing what it wanted in the form of alien life.
The missions of Viking 1 and 2 were more provocative than the flybys of the Mariner satellites. These two satellites carried Martian rovers which would observe the landscape and do soil experimentation. Viking 1 deployed its lander on July 20, 1976, and started moving about the Martian surface. The first images from the surface confirmed orbital photos, which showed a rocky and crater pocked planet. The soil experiments, perhaps the greater priority of the mission, were at first hopeful. Several types of experiments that were aimed at receiving reactions to terrestrial elements produced some reaction. But this was due to the type of soil that Mars had, not any biological means. The lander did give scientists some very good information; generally that Mars was a cold planet with low atmospheric pressure. Seasonal changes brought high winds, dust storms, and higher pressure systems. The planet would finally be entirely mapped by the Russian Phobos 1 and 2 in July 1988.
The exploration of Mars continues to this day, largely with less public support than in previous missions. Still, some scientists and members of the public alike hold out hope for life on Mars, even in microscopic form. This is the product of both curiosity and the opinion that science has not conclusively brought an end to the possibility of life on Mars. The questions of these hopefuls are related to the means of experimentation, the possibility that we are doing the wrongs types of experiments to determine life. However, these means are all we have until we determine more efficient processes of scientific discovery. This is always possible, given the rapid proliferation of computers over the last two decades as an example of technological progress. Mars is still the subject of controversy, now part of the problem of whether it is worthwhile to do these experiments or not. It will always be the subject of scandal and fantasy until we have conquered it, either literally or metaphorically, and have cast away the illusions of the human imagination.
Brewer, Duncan. Planet Guides: Mars. New York: Marshall Cavendish, 1992. Corrick, James J. Mars. New York: Franklin Watts, 1991. Sheehan, William. The Planet Mars: A History of Observation and Discovery. Tucson: The University of Arizona Press, 1996.
