Going Home
Nonfiction – by Peter Jekel
What makes the desert beautiful is that somewhere it hides a well. Antoine de Saint-Exupery
“We interrupt this program,” was how the program began. Orson Welles shot to fame when he did his radio play from his Mercury Studio on October 30, 1938, based on H. G. Wells’ 1897 classic novel, War of the Worlds about an invasion of Earth by Martians. The story was changed from an invasion in England as in Wells’ novel to an invasion of Grover’s Mill, New Jersey. The broadcast, performed against the backdrop of the impending Second World War, as a series of simulated newscasts lent the show a “feel” of authenticity, this in spite of numerous statements during the broadcast made to indicate that it was just a radio play and fictional. Even with the repeated warnings, newspapers reported panic in northeastern United States and Canada.
Whatever the reasons, there certainly was an appetite that led at least some people to believe that life on Mars and hence Martian invaders were a real possibility. As early as 1854, scientist and theologian William Whewell of Trinity College in Cambridge, England first speculated that the planet Mars was earth-like with oceans, land and hence life. In 1877, Italian astronomer Giovanni Schiaparelli saw through his telescope a network of what he described as “canali” or channels on the surface of the planet possibly the result of water flow.
It was American astronomer, Percival Lowell, who was also famous for calculating the presence of a planet beyond Neptune, Pluto (no longer classified as a planet) who trumped Schiaparelli’s observations to the extreme and speculated that the “canali” were active and artificial irrigation channels for a dry and dying world. He described his theories in two books, Mars in 1885 and Mars and its Canals in 1906. As if to almost lend credence to Lowell’s theory of a dying civilization needing to maximize their water resources, spectroscopic analysis of the Martian atmosphere in 1894 by American astronomer William Campbell showed that water and oxygen were all but non-existent in the atmosphere.
It was science fiction author H. G. Wells who saw opportunity in these “canals” and created his science fiction masterpiece The War of the Worlds, about an alien Martian invader seeking a new home to start their society anew; the canals were seen as an indication of their drying and dying civilization.
Wells’ vision of invading Martians is also realized again in Olaf Stapleton’s 1930 time-spanning tale, Last and First Men, which describes an Earth of the distant future being invaded by Martians seeking to exploit our resources. Dennis Wheatley, better known for his novels of the supernatural, wrote his 1952 novel Star of Ill-Omen. In his story the Martians initially invade the Earth not to conquer but instead, to kidnap humans in order to learn how to make nuclear weapons which are to be used to head the upcoming conquering invasion of Earth.
Other early authors also saw Mars as a haven for alien life not just as a source of invading armies. In fact, there are probably more science fiction novels and stories with Mars as a setting than any other place in the universe including Earth itself.
As early as 1880, Percy Greg wrote Across the Zodiac, about an astronaut visiting alien beings on Mars. In a reversal of fortunes for the invading Martians, Garrett P. Serviss, in 1898 wrote Edison’s Conquest of Mars, about humans annihilating Martians in retaliation of an earlier Martian invasion of Earth. A more light-hearted story of Mars was A Honeymoon in Space, written by George Griffith in 1900, about a couple travelling through the solar system only to be intercepted by Martians. French author Arnould Galopin’s 1906 Doctor Omega is about a mission to Mars where the explorers find a planet inhabited by a plethora of strange beings often found in many simplistic science fiction stories including reptilian mermen, dwarfs with long-tentacled arms, bat men and bulbous-headed dwarves. Edgar Rice Burroughs, whose main claim to fame was the creation of the ape-man, Tarzan, wrote numerous stories (the John Carter series, 1912-1943) about a Virginia gentleman named John Carter who finds himself mysteriously displaced to a Mars inhabited by several native intelligences and numerous bizarre animals.
Stanley Weinbaum, in 1934, broke new ground in a short story, A Martian Odyssey. In his story he depicts Martians differently from earlier writers. His Martians are not evil and bent on conquering Earth. Nor are they beings who are really nothing more than mutant versions of human beings. Instead, Weinbaum’s Martians are sympathetic beings but who think in a manner very unlike what is found in humans.
C. S. Lewis wrote in 1938, Out of the Silent Planet, about Martians that are also found to be very sympathetic and intelligent beings, not unlike Weinbaum’s aliens. Lewis’ Martians had contemplated the invasion of the Earth in our deep past when their planet began to die; however, they soon dismissed the idea and resigned themselves to let nature take its course and die out.
Ray Bradbury wrote his 1950 classic fantasy The Martian Chronicles which has Martians that are essentially human but for their copper-colored skin and telepathic abilities. Bradbury’s Martians succumb to human disease introduced by human explorers who land on the alien world, not unlike the Martians in Wells’ in War of the Worlds. In 1951 Arthur C. Clarke’s The Sands of Mars follows the exploits of a science fiction writer looking for inspiration on a trip to a colonized Mars.
Later authors saw Mars as a planet to colonize. One of the first is Scottish author J. T. McIntosh’s 1954 story One in Three Hundred, about an attempt to colonize the Martian world as increased solar activity causes the Earth’s oceans to boil away; it is interesting that this story probably resonates more with the reader than when it was originally written. Jerry Pournelle’s Birth of Fire is about a youth transported to Mars as a convict laborer who becomes involved with a group of rebels seeking to terraform Mars and break the domination of corporations and domed cities. Robert Heinlein’s Red Planet and Greg Bear’s Moving Mars also depict a Martian colony rebelling against their masters from Earth.
All of the speculation and in some cases, the horror of possible life on Mars was finally put to rest with the flyby by NASA’s Mariner 4 in 1964. There was a Mariner 3 that was launched concurrently with Mariner 4; however, Mariner 3 never made it to its Martian destination. Mariner 4, though, was successful and gave us our first true glimpse of the red planet. What the spacecraft showed was really unlike anything described before or even expected; in fact, it appeared to be somewhat of a letdown. Now we had a world that appeared not to harbor life, at least not civilized life, but appeared to be little different from the pockmarked surface of our Moon. Unlike the Moon, Mars was found to have an atmosphere, but it was only at about one percent that of the Earth’s pressure. The daytime temperatures of Mars hovered around minus 100 degrees Celsius, not enough to eliminate the possibility of life as we know it but a serious blow nonetheless. No magnetic field was detected which meant that the cosmic rays of the heavens irradiated the surface, further lessening the potential of life as we know it.
Mariner 4 may have dampened the dreams of science fiction enthusiasts and probably many scientists as well, hoping for some possibility of life; however, to some it was an opportunity, an opportunity to explore new ideas and redesigning future probes to test those ideas.
NASA would continue with its Mariner program with another landmark happening when Mariner 9 was able to achieve orbit around Mars in 1971, the first time any human made spacecraft did so. In addition, Mariner 9 found a planet-wide dust storm in progress. Mars was hardly the static dry world that Mariner 4 depicted; there was very active weather on the planet.
Mariner 9 also took, once the storm had cleared, photographs that depicted evidence that liquid water once may have flowed on the surface of Mars in what appeared to be dried-up river beds. There were photographs of what would turn out to be the highest mountain in the entire solar system. Scientists named it Olympus Mons which is Latin for Mount Olympus, home of the pantheon of Greek and Roman gods. To state that Olympus Mons is tall is somewhat of an understatement. It stands nearly three times higher than our highest mountain here on Earth, Mount Everest; Olympus Mons towers 22 kilometers above the planet surface of Mars.
The grandeur of the enormous volcano has not been lost on speculative fiction authors either. One, "Olympus Mons," is a classic short story about a skiing competition down the volcano, by Bud Sparhawk, that provides vivid descriptions of the volcano. Ben Bova, too, wrote a short story entitled "Olympus Mons" as well, but in this story, astronauts explore the caldera of the giant volcano searching for microscopic life. Brian Aldiss’ short story entitled "The Difficulties Involved in Photographing Nix Olympica" is about an army sergeant obsessed with photographing the volcano.
Olympus Mons is found in an elevated region on Mars known as the Tharsis region along the boundary separating the northern and southern hemisphere. The Tharsis region also contains at least two other extinct volcanoes. There are several smaller volcanoes also known as tholi.
The other volcanic region of Mars is known as the Elysium province which lies several hundred kilometers west of Tharsis. The volcanoes here, though, large by Earth standards, are smaller than those found in Tharsis province.
Why are the volcanoes of Mars so large? Volcanic activity played a large role in Mars’ past and achieved such great size largely due the lack of plate tectonics which allowed regions to be geologically active for many millennia thus allowing a massive buildup of material. Plate tectonics, which is the movement of plates of a planet’s surface over the interior, is driven by the interior heat of a planet. Since Mars is only slightly more than half of the Earth’s size and it is just slightly more than one and a half the distance from the life-giving heat of the sun, its interior would have cooled many millennia ago.
Extending eastward from Tharsis for a length of four thousand kilometers, about a quarter of the planet’s circumference is a series of deep interconnected canyons known as Valles Marineris. It has been compared to the Grand Canyon but with a very different origin. Whereas the Grand Canyon was created by water erosion the Valles Marineris appears to have been born out of a process similar to that of the African Rift Valley. Another theory is that the deep chasm, up to eight kilometers deep, six hundred kilometers wide and three thousand kilometers long , may have begun as a simple crack as the surface began to cool. One can only imagine the splendor of this formation since the Grand Canyon, by comparison, awesome in its own right, is only 1.8 kilometers deep, thirty kilometers wide and eight-hundred kilometers long.
To the east of the Valles Marineris is a dense series of low rounded hills that seem to have formed by the collapse of upland surfaces to form broad, rubble-filled hollows. They appear like the heads of huge water outflow channels not unlike those found on Earth often associated with the melting of subsurface ice. One discharge that carved the 28 kilometers wide Ares Vallis is estimated to have had an outflow greater than found in any river system on Earth.
There is a dichotomy between the two hemispheres of Mars. Whereas the north is seen as a large depression, generally three to six kilometers lower when compared with the south, it also is less-pockmarked with impact craters and possesses a thinner crust. On the other hand, the south is generally very pockmarked and possesses a thicker crust. There are several ideas that explain the differences, but an enormous impact in Mars’ past appears to be favoured by many scientists.
Though Mariner spacecraft showed evidence of past water activity, more recent probes went further in the search for evidence of water on Mars. In 1997, NASA successfully orbited the Mars Global Surveyor around the planet. During its low altitude study of the planet it found evidence of gullies and debris that suggested that there may be current sources of liquid water similar to an aquifer at or near the surface. Magnetometers aboard the spacecraft also found that there is also a weak magnetic field on Mars. It is not globally generated by the planet’s core like Earth’s but rather is localized in the crust of Mars. Mars, though, at one time did possess a global magnetic field.
NASA’s Mars Atmosphere and Volatile Evolution Mission (MAVEN) launched in 2013 as part of the Mars Scout Program, has just now found that the magnetic field of Mars also has a magnetic tail that has been twisted by its interaction with the solar wind which is known as magnetic reconnection. This in turn, would support another mechanism by which Mars lost much of its atmosphere and magnetic field billions of years ago as ions of gasses in the upper atmosphere would follow the magnetic twist into outer space.
In 2001, NASA’s Mars Odyssey’s gamma ray spectrometer detected significant amounts of hydrogen in the upper meter of the regolith (soil) on Mars suggesting large deposits of water ice. The still-active Opportunity Rover launched by NASA in 2003 and landing in 2004 found further evidence of water on the planet. Some of the surface layers on Mars could have been caused by groundwater rising to the surface in many places, especially inside of craters.
Other Martian exploring devices have analyzed the atmosphere of Mars and found many surprises as well. In 2004, the European Space Agency announced that its Mars Express spectrometer detected methane in the Martian atmosphere and aurorae on Mars in 2006. More recently MAVEN, too, has detected an ultraviolet aurorae spanning the entire globe during an intense solar storm. Though the methane detected by Mars Express could be an indicator of life, it is not conclusive as it could also originate through volcanic or hydrothermal activity.
The atmosphere of Mars, in general, though a lot thinner than ours here on Earth, is made of almost 96 percent carbon dioxide with traces of other gasses such as nitrogen, argon, oxygen, carbon monoxide and water vapor.
That was not always the case though. Once there was a thicker atmosphere and even a magnetic field. What happened? One speculation is that around sixteen million years ago there was a massive impact event on Mars that stripped away much of the atmosphere and the magnetic field rendering the planet potentially lifeless.
Such an impact would also be a good explanation for the geological contrast between the northern and southern hemisphere. There may also have been several mechanisms at play as demonstrated by the recent data from the MAVEN mission regarding the planet’s twisted magnetic field. MAVEN data appears to show, however, that the main mechanism of atmospheric loss, was through the gradual stripping away by solar wind; this is based on the fact that in the past the radiation output of the sun around the time that Mars lost much of its atmosphere, was more intense in the past than it is today.
In spite of all of the adversity to life as we know it that Mars dishes out, all is not lost. If life is still present, it is most likely microbial in nature living in fluids or sediments, and results from some recent spacecraft are promising. Soil and rock samples analyzed by NASA’s Curiosity Rover’s, launched in 2011, onboard instruments showed that there were also clay minerals suggesting a wetter past. The Mars Reconnaissance Orbiter launched by NASA in 2005 discovered extensive evidence of liquid water currently on Mars: water ice in the Martian north polar ice caps, water ice in craters, and, most interestingly, evidence of running water. With its imaging spectrometer it found evidence of hydrated minerals that appear much like what one might observe in river basins on Earth during wet and dry seasons. Even with this evidence, however, to date, no definitive evidence of Martian life, past or present, has been found.
Could life exist today on Mars and if not today, did it exist in the past? It was two NASA spacecraft, Viking 1 and 2 launched in 1975 to Mars to determine whether or not life existed on the surface of Mars today. The program consisted of two orbiters and two landers; they were the first craft to successfully land on the red planet’s surface. The goal of the lander missions was to search for any signs of life as well as observing meteorological, seismic and magnetic properties of Mars. Unfortunately, the biological experiments on board the Viking landers were inconclusive as the results could have been the result of chemical rather than biological reactions. Recently, however, an article published in 2012 analyzed the data again and concluded that there is microbial life on Mars based on the Viking findings. Regrettably, there is no consensus on this hypothesis.
Interestingly enough, some speculate that the Viking spacecraft not only found evidence of life on Mars but intelligent life as well. The “Face of Mars” which was photographed by both Vikings on flyovers of the Cydonia region of the northern hemisphere of Mars. NASA insists that the face is merely a lighting anomaly and base their explanation on subsequent photographs by future Mars probes as well as enhanced computer imaging technology. NASA is probably right but isn’t it great to imagine otherwise?
One science fiction author at least has written a story, about the Viking probes. In A World of Difference, set in an alternate universe, Harry Turtledove describes a picture sent back by a Viking lander that actually shows an alien in it; the Mars of this universe, called Minerva, is far more conducive to life. In the story, the United States and Soviet Russia quickly respond to the Viking image with rare cooperation to explore the planet.
In spite of all of the evidence that would seem to indicate that Mars could be conducive to life, many scientists believe that, based on the irradiation of the surface, Mars is probably lifeless. But that says nothing about deeper down. Some hypotheses speculate that microbes could possibly exist up to 7.5 meters below the surface.
Some science fiction authors have speculated on the finding of underground life on Mars. One author from the Golden Era of science fiction, Isaac Asimov, in his David Starr, Space Ranger, wrote about an explorer who discovers a Martian civilization deep beneath the Martian surface. More recent novels also speculate on life beneath the Martian surface. Martian Race by Gregory Benford describes a mission to Mars only to find life hidden away in deep chasms on the planet. In Ben Bova’s Grand Tour series there are a couple of novels about Mars, Mars and Mars Life, that not only depicts underground Martian life but also a lost civilization found on a cliffside of the planet.
There is other evidence of life on Mars, but ironically it was not found on Mars. Just after Christmas in 1984, a meteorite was found in the Allan Hills, Antarctica, and named Allan Hills 84001 or ALH 84001. The meteorite came from Mars over four billion years ago, at a time when Mars was likely more hospitable to life than it is today, probably as a result of a cataclysmic collision which ejected the rock on a trajectory with Earth. Such an event may have not been the first either. There is some scientific thought that organic molecules from other worlds including Mars could have kick started evolution of life on Earth, sometimes known as panspermia. In effect, we may all be Martians.
The Martian panspermia theory has also resonated with at least one science fiction author as well. In an expansion of this theme of life on Earth arising from Mars, H. Beam Piper wrote a short story, Genesis, where the humanoids of Mars flee their dying world around 100 thousand BC. When their ship is destroyed by meteors, only two men and six women are able to land in a lifeboat and become the ancestors of humans.
At the time of its discovery, ALH 84001 did not rock the scientific community. It was the analysis of ALH 84001 that made headlines in 1996 when scientists announced that they had found evidence of microscopic fossils of Martian bacteria on carbonate globules. Even then-President Bill Clinton made a televised announcement to mark the event. There is, however, no agreement on whether or not the globules are evidence of microscopic Martian bacteria or the remnants of some inorganic activity.
As if in response to the controversy, Dan Brown’s conspiracy thriller Deception Point, published in 2001, is about a discovery of alien fossils in a meteorite found in the Arctic is covered up by government officials who do not want the information to become public. Robert Sawyer wrote in his book, Red Planet Blues, the finding of fossils on the planet resulting in a Martian Fossil Rush not unlike the Klondike gold rush of the late nineteenth century.
One speculation about not just life but intelligent life on Mars comes from its two moons first discovered by American astronomer Asaph Hall in 1877. The intelligent life speculation may have actually started as an April Fools’ joke. In 1959, Walter Houston, an amateur astronomy writer perpetrated an April Fool’s hoax in an April edition of an amateur astronomy publication which claimed that Dr. Arthur Hayall of the University of the Sierras, both fictitious, reported that the moons of Mars are artificial. The hoax gained worldwide attention when the claim was repeated by Soviet scientist Iosif Shklovsky, the coauthor with Dr. Carl Sagan of the groundbreaking book, Intelligent Life in the Universe. He had done some calculations on the moons and made the determination that they could very well be hollow leading to speculation that they might be spacecraft.
Though fascinating that the moons might be alien spacecraft, the Martian moons, Phobos and Deimos, are probably captured asteroids. They also happen to be a couple of the darkest objects in the solar system, reflecting very little light. They were actually first mentioned in Jonathan Swift’s Gulliver’s Travels as early as 1735, well before their discovery, which has his Laputan astronomers describing two satellites of Mars orbiting at distances of three and five Martian diameters and periods of 10 and 21.5 hours respectively. The actual distances are 1.4 and 3.5 Martian diameters and 7.6 and 30.3 hours respectively. How Swift knew of the moons is difficult to say, but some speculation is that he extrapolated from the moons that were known at the time. Earth had one moon and Jupiter had four. Therefore, in the interest of a logical progression, Mars, which lies between Earth and Jupiter, must have two moons. Swift was not the only early writer to mention two moons of Mars either. In 1750, Voltaire’s short story, Micromegas, about an alien visitor to Earth mentions two moons of Mars.
The possibility of life on Mars remains to be seen, but what about human habitation of the planet? With the intense radiation hitting the surface of Mars along with the thin atmosphere, it is too inhospitable for human life. We could build isolated shielded communities. Philip K. Dick wrote of a Mars that was empty and dry with only isolated communities in Martian Time Slip and The Three Stigmata of Palmer Eldritch.
Engineers have also speculated on how to make Mars habitable for people beyond having them live underground or in shielded domes and that is through a process known as terraforming. Terraforming is a process whereby engineers create conditions where a planet can be changed into a habitable planet for humans. The term “terraforming” has its origins in science fiction, when Jack Williamson coined the term in his 1942 short story, Collision Orbit.
In order to terraform a planet such as Mars, the goal is to build up the scant atmosphere by increasing its pressure. By doing so, the atmosphere can then more readily retain heat. One idea is that through the placement of well-positioned orbital mirrors, the polar ice caps, made up mainly of frozen carbon dioxide and water, both greenhouse gasses, would begin to sublimate further releasing even more carbon dioxide and water into the atmosphere. This would increase atmospheric pressure and also stabilize the surface temperature of the planet.
It is estimated that there is enough carbon dioxide in the Martian south pole and in the Martian regolith that, if sublimated, would increase atmospheric pressure to a level comparable to the peak of Mount Everest. Not an ideal condition for humans; however, there have been climbers who have ascended the peak without the assistance of oxygen.
Some other ideas for terraforming Mars have included importation of ammonia (a strong greenhouse gas) from the gas giant planets or through the introduction of hydrocarbons from Titan to build up the atmosphere of Mars. Another idea that has been proposed is the introduction of hardy Earth algae and other microorganisms onto Mars for its gradual transformation of the planet’s atmosphere much like what occurred in Earth’s ancient past.
In a model for the colonization of Mars developed by Robert Zubrin with Richard Wagner in their book, The Case for Mars: The Plan to Settle the Red Planet and Why We Must, show that by raising the temperature of Mars just four degrees Celsius, we would begin to see a runaway greenhouse effect. Kim Stanley Robinson’s fictional Mars trilogy and its standalone novel, The Martians, stand as classic works on the progressive transformation of Mars from a dry alien world into another Earth.
Other authors have looked at the terraforming of Mars. The setting of Kevin Anderson’s novel Climbing Olympus, features Mars in the midst of being terraformed. Red Dust by Paul McAuley takes place against a failed attempt of terraforming Mars by the Chinese. Mars Underground by astronomer William Hartmann is about a partially terraformed Mars.
In a real twist on the terraforming theme, Larry Niven envisions it being done in spite of intelligent Martians already living there. In Larry Niven’s novel Protector, part of the Known Space series, the Martians are exterminated by the deliberate crashing of a water asteroid which turns out to be highly toxic to the Martians.
In S. M. Stirling’s Lords of Creation alternate universe series, there is a description of a Mars that had been terraformed not by humans, but by an alien race. In the story, Martians are still found on the planet but in a downward societal spiral, this in spite of once having been highly advanced.
As if in protest to the idea of terraforming the planet, Brian Aldiss and Roger Penrose wrote White Mars that effectively rejects the idea of terraforming as Mars and rather keeping it as a planet for science similar to Antarctica today.
At least one author has speculated that if you cannot change the planet, perhaps we can create humans that can survive under current conditions on Mars. In the award-winning Man Plus, Frederick Pohl has his character adapt to Mars by transforming into a cyborg capable of surviving on the planet’s hostile surface.
All of the recent interest in Mars by NASA and other space agencies is not lost on science fiction authors who have written extensively on the human exploration of the planet. One of the first was by Ludek Pesek whose 1975 The Earth is Near depicts a very realistic mission to Mars. Stephen Baxter, in his novel Voyage, which takes place in an alternate universe, describes a manned mission to Mars undertaken by NASA in the present day. Geoffrey Landis, a NASA scientist, wrote Mars Crossing about a mission to Mars that becomes stranded.
Aerospace engineer Robert Zubrin in his novel First Landing took his lifelong passion for Mars and wrote of the first mission to the planet by humans using some of the technology and ideas from his nonfiction books. Science fiction pioneer and legend, Jack Williamson wrote a Mars exploration novel, Beachhead.
A best-selling novel that describes the exploration of Mars gone wrong is Andrew Weir’s debut novel, The Martian. It is a story about an explorer left stranded on Mars after his exploratory team concludes that he died during a Martian dust storm, leaving him behind.
Mars has always fascinated humankind ever since we first looked up to the heavens. Its red color was so different from the panorama of stars in the night sky. Later civilizations looked at this “red star” and saw an angry god of war, and named it Ares and later Mars. Just when we think that we know the planet, another probe or astronomical observation finds something new and unexpected only to whet the appetite for further exploration. There are a number of future probes planned by various space agencies for the exploration of Mars including including having humans land on the surface as soon as 2030. If we are to put some credence to the Martian panspermia theory, when we first step onto the Martian surface, we may not actually be stepping onto a new world, but merely coming home.
Further Reading
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