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How Humans Will Live on Mars
The red planet has mystified and enraptured the people of Earth since ancient times. Space exploration has grown in recent decades and is now branching out to an exciting new prospect: sending humans to Mars. This mission comes several decades after we sent humans to the moon. What has taken so long? Can it even be done?
In 1950, before the general public or even scientists had much data about Mars, Ray Bradbury published a short story collection entitled The Martian Chronicles. Within it, he described how Earthlings eventually began to migrate to Mars and colonize it—a process which was hastened by the serious threat of nuclear war on Earth. Bradbury’s Martian environment was more like the Garden of Eden than the Mars we know today, with flowing water, enough oxygen to breathe, plant life, natives with odd features and incredible abilities, and no need for humans to wear spacesuits (Bradbury 1950). Considering rather little was known about the planet, imagination was allowed to run free and many people began to cling to such an idea of the Martian landscape, perhaps even with the Martians described in Bradbury’s stories living there.
Fifteen years after the publication of The Martian Chronicles, the NASA probe Mariner 4 completed the first successful Mars flyby. This wonderful and terrible mission reported surprising new information. The first shock was that far from being breathable, the Martian atmosphere was extremely tenuous. The temperature was also much cooler than had been previously imagined (partially due to its almost complete lack of an atmosphere). The probe detected no magnetic field, leaving the surface exposed to cosmic and solar radiation (Grayzeck 2016). Life on such a world seemed extremely unlikely.
In spite of this disappointing news, interest in Mars has continued throughout the years. There are plans now in place to send humans to Mars, which thanks to Mariner 4 and subsequent Mars missions we know will not be easy. There are four primary needs which humans on Mars will have, all of which may be difficult but not impossible to secure. These are food, water, shelter, and clothing.
The Martian environment as it is now is not exactly conducive to farming. As most people know, plants take in carbon dioxide and release oxygen. Carbon dioxide makes up 95% of the Martian atmosphere, but as previously mentioned the atmosphere is extremely tenuous (Zubrin 2011, 5). Plants also require sunlight, which they would receive on the surface of Mars—but they would also be subject to high amounts of radiation. Then there are the freezing temperatures, which would make it extremely difficult for plant life to flourish on the Martian surface.
There is, however, evidence of liquid water flowing on the modern surface of Mars, which is great news for both plant and human life (Brown 2015). This is key for human space travel, as water is heavy and can take up large amounts of a mission’s space and weight allotments. Having it on Mars already would be a tremendous step in several ways. It would be great not only for humans and eventually plants to flourish, but it could greatly reduce the cost of a Mars mission. Rocket fuel is extremely expensive, and having to transport the fuel required for the return trip increases the weight and space requirements. The heavier and larger a craft is that has to leave Earth, the more is lift is necessary. It could be something like a case of getting a round trip ticket for the price of a one way.
Water on Mars would also be great news for human explorers, as it can be separated to obtain the oxygen we need to breathe. There may not be enough liquid water on the surface for the various human requirements, however it is quite possible that there exist underground aquifers containing much larger amounts (Petranek 2015, 42). The human requirement for water would obviously be fulfilled (if it is not drinkable naturally it could no doubt be purified to within acceptable limits), it would reduce mission costs by providing rocket fuel, and it would be far easier to grow crops which people could eat.
In a small way, utilizing water to grow crops could be a step in planetary engineering, or “terraforming” the Martian environment to be suitable for human habitation. Plants would help increase the amount of oxygen in the Martian atmosphere. Experts estimate that true terraforming of Mars would take maybe as much as a thousand years, but the sooner the process is started the sooner the result will be achieved (Petranek 2015, 65). There may come a day when humans are forced to colonize Mars, so any amount of terraforming would be extremely beneficial—if not for us, for future posterity.
As far as shelter is concerned, humans on Mars will require more than just standard housing. This is due to the fact that it lacks a magnetic field and has such a thin atmosphere—there is very little protection from both solar and cosmic radiation (Zubrin 2011, 13). The pressurized pop-up dwellings that are likely to be brought on early missions are only a temporary solution, and constructing buildings of material that will sufficiently shield humans from the radiation is a long-term goal. One of the ways to construct habitats on Mars may eventually be to dig into the ground, sort of like the Anasazi villages of older times on Earth. The issue would be to sort out pressurization, to ensure humans could still breathe and fully function in such an environment. In the meantime, a cost effective and relatively simple and easy solution would be to dig out dwellings or at least construct above ground buildings in the pueblo style—out of dried mud or clay bricks (again, assuming the pressurization could be achieved) (Petranek 2016, 52).
The partiality toward in situ resource utilization, as previously mentioned, greatly reduces the cost of interplanetary missions. If water, shelter, rocket fuel, and eventually food can be sourced locally on Mars, the cost of transporting these resources will be eliminated. Today, the biggest barrier to interplanetary travel is the exorbitant cost. We have the technology required to complete such travels, and no doubt improved technology will be developed. The financial burden is too high to effect a Mars mission immediately, but hopefully the idea will generate enough support from the general public as well as governmental officials that the finances will be allocated.
Some of the proposed technologies for obtaining oxygen from the Martian atmosphere and water from deep underground are not fully proven—more particularly the latter—and human lives are a high value to gamble. Space agencies are keen to exercise caution, for the sake of human lives and the survival of a Mars mission. A tragedy would be severely damaging to support for an interplanetary mission, and the financial risk is very high as well. Scientists will need to prove the technologies that are available before such a mission can be completed.
Perhaps the most easily solved issue is that of clothing. Like with the shelter issue, specialization for the Martian environment is key, primarily due to the dangers surrounding the radiation experienced on the surface. It is also, of course, rather cold on Mars. The average temperature is well below freezing, at a chilly -81 degrees Fahrenheit (“Mars Facts” 2015). In addition, Mars’s lack of atmospheric pressure can be mitigated by specialized clothing. The human body exerts a force outward which is combatted by atmospheric pressure pressing inward. The Martian atmospheric pressure is too low to counter the outward force human bodies naturally exert. So clothing for human Mars explorers will have three main things to combat: radiation, cold, and low atmospheric pressure.
Fortunately, MIT’s Dava Newman is working on a solution. She reasons that the human body only truly requires around a third of Earth’s atmospheric pressure, and she has designed a “second-skin” clothing design that she believes will do the trick. It is designed to allow much better agility, as well as weigh far less than the standard large, inflexible, bulky spacesuits. The radiation factor is not highly considered in Newman’s design, as “real shielding is heavy and massive” (Petranek 2015, 53). She believes that humans on Mars will spend the majority of their time inside protected environments anyway, such as rovers or radiation-shielded dwellings.
Even with protective clothing and shelter, extra care will need to be taken in the event of a solar flare or other Sun activity that will cause a burst of greatly increased radiation. According to Stephen Petranek, author of How We’ll Live on Mars, “People on Mars will need shelter with as many feet of regolith or rock above their heads as possible. A solar storm directed Mars’s way will require shelter in a deep cave or the like” (Petranek 2015, 52). If and when Mars is terraformed, the density of the atmosphere will increase enough so that radiation will be of little concern.
A serious problem may be the effects of extended interplanetary travel within a zero gravity environment. In 1952, German engineer and rocket scientist Wernher von Braun published a manual about space exploration, specifically targeting the planet Mars. Within Das Marsprojekt (The Mars Project), von Braun suggested a fleet of connected spacecraft which would be spun around to create artificial gravity. He was incredibly far ahead of his time, as scientists have now verified dangers due to muscular atrophy resulting from extended periods spent in zero gravity. The technology required to build such a system as von Braun suggested may still be out of reach, but scientists are gathering ever increasing amounts of data about the effects of zero gravity on humans. NASA astronaut Scott Kelly and Russian cosmonaut Mikhail Korniyenko began a one year stay aboard the ISS in zero gravity in March of 2015. Scientists hope to gather more data about the effects of a zero gravity environment on human physiology by observing each of these men. It is hoped that human bodies may adapt to some degree to the harsh space environment.
At any rate, weight on Mars itself may not be as much of an issue. It experiences a third of Earth’s gravity, and additional weight could be incorporated into clothing to prevent muscular deterioration. Early life on Mars will likely be physically grueling anyway, as access to modern technology will of course be limited. Early Mars explorers, much like pilgrims traveling to the new world, will have a lot of work to do in order to travel to and eventually colonize the red planet. It will be necessary at some point, however, because even if we find solutions to the energy crisis, find ways to feed the population and control its growth, prevent nuclear wars, and correct the vast environmental changes we have induced, the Sun will someday swell to become a red giant. It may even extend far enough to encompass the Earth’s orbit, so any human inhabitants that remain will be scorched to death (Phillips 2012). Getting humans to Mars to visit and eventually colonize the planet will require much, but if our species is to survive it must be done.
Bradbury, Ray. The Martian Chronicles. New York: Simon & Schuster, 1950.
Brown, Dwayne, and Laurie Cantillo. "NASA Confirms Evidence That Liquid Water Flows on Today’s Mars." NASA. September 28, 2015. Accessed February 2, 2016. http://www.nasa.gov/press-release/nasa-confirms-evidence-that-liquid-water-flows-on-today-s-mars.
Grayzeck, Ed. "Mariner 4." NASA Space Science Data Coordinated Archive. February 12, 2016. Accessed February 13, 2016. http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=1964-077A.
"Mars Facts." NASA: Mars Exploration. October 15, 2015. Accessed February 2, 2016. http://www.mars.nasa.gov/allaboutmars/facts/.
Petranek, Stephen L. How We’ll Live on Mars. New York: Simon & Schuster, 2015
Phillips, Tony. "Fried Planets." Nasa Science News. October 25, 2012. Accessed January 26, 2016. http://www.science.nasa.gov/science-news/science-at-nasa/2012/25oct_friedplanets/.
Zubrin, Robert. The Case for Mars: The Plan to Settle Mars and Why We Must. New York: Simon & Schuster, 2011.