Introduction
For decades, Martian exploration has been an objective of humanity’s space programs. The motives for this undertaking vary from a desire to better know Earth’s stellar neighborhood, to seeking other spheres of life and evidence about life’s origins, to a desire for new frontiers for man to settle. Mars is Earth’s closest planetary neighbor other than Venus, and has the friendlier environment of the two by far (simply contrast a thin, cold atmosphere and a barren rock surface with a scalding-hot atmosphere thick with sulfuric acid and a semi-molten surface). Mars has been found to contain an abundance of all basic elements requisite to life, and is theorized to have even hosted life in the past. These desires and findings have led scientists to recently theorize and begin planning for eventual human settlements on Mars. In addition, some propose that terraformation be undertaken in order to make all of Mars hospitable to humans and other terrestrial lifeforms.
Astrobiology can be greatly furthered by manned Martian settlements. The direct methods made available by human researchers will allow for much more meticulous searches for evidence of life’s prior existence on Mars. Even if searches for Martian life prove completely unfruitful, there is much astrobiological insight yet to be gained. The ability to observe the behavior of terrestrial organisms in an extraterrestrial planetary environment will provide much deeper insight into the nature of life, its potential for diverse adaptation, and its extremes of tolerance. All this will enrich man’s understanding of life, as well as the potential for life on other worlds beyond Earth and Mars.
Another, more pressing motivating factor behind the establishment of human settlements on Mars is the expansion of human habitation. Many believe that by spreading humanity to settlements beyond the Earth—including not only Mars, but asteroid colonies and the colonization of other planets in this and other star systems—the species will increase its probability of survival. Some take the concept further still, as a manifest destiny to expand to the next frontier of human advancement.
Background
Martian exploration is a human mission now about half a century old. The first attempt at a Mars flyby observation was executed by the Soviet Union in October of 1960 with the secret launch of the craft Marsnik 1, which was unsuccessful. The first successful Martian flyby was executed in 1964 by the NASA probe Mariner 4, which provided humanity’s first proximally obtained photographs of the planet’s surface. Since then, many dozens successful missions have been executed for the exploration of Mars, including orbital flybys, landing craft, and surface-roving robots. Three Martian rover missions have been successfully executed since the 1990s. Each of these rovers has provided substantial amounts of information about the Martian environment, specifically with regard to the planet’s geology and geography.
These missions have greatly enhanced humanity’s understanding of Mars, but the potential for Martian knowledge has only barely been tapped. Manned research will provide direct observation and hands-on, versatile conditions far superior to any remote robot can provide. Lunar missions, both past and future, will have provided humanity with the requisite practice in the execution of manned extraterrestrial missions to enable the undertaking of the much more complex challenge of landing humans on Mars.
Manned spaceflight has been a reality since Soviet cosmonaut Yuri Gagarin undertook a successful orbit of the Earth in 1961. The spaceflight breakthrough most relevant to setting a precedent for Martian missions, however, was the 1969 NASA mission, Apollo 11, in which Neil Armstrong and Buzz Aldrin became the first two humans to land on the moon. Exploration of Earth’s moon provides an excellent analog for future Martian flights, providing samples of the conditions such as the effects of reduced gravity over extended periods on the human body, the psychological and physical effects of long-term crew confinement in a small vessel, and the effectiveness of astronaut life-support systems, and the dynamics of extraterrestrial surface rovers.
The Martian settlement agenda has been pushed heavily of late by organizations such as the Mars Society and popular thinkers like Stephen Hawking. The primary motivating factor behind these high-publicity promotions is human expansion, both as human survivability insurance as well as what is proposed as the next great step in the progress of humankind.
Current Information
Martian settlements, being a field of future speculation, have little in the way of tangible findings per se, but instead remains currently defined and embodied by scientifically speculative planning. The requisites and proposed methodologies are predominantly theoretical, with no direct precedent for sustainable extraterrestrial settlement. However, analog experiments, Martian environmental simulators, and the precedent of manned spaceflight have all been used to create viable models for future colonization.
With a history of 48 years, human spaceflight has been developed, studied, and refined quite extensively. Throughout this process, the science of human survivability in extraterrestrial environments has been developed as a facet. Humans are able to survive in outer space, sometimes for weeks at a time, with the help of life support technology developed for precisely such a purpose. In the future, such technologies can be applied to sustaining the life of colonists on an inhospitable Mars.
Manned lunar missions, planned to recommence within the next decade, will require the further development of much space travel technology, as well as surface negotiation robotics, such as the ATHLETE rover. The ATHLETE, scheduled for construction for the next set of lunar landings, doubles as a potential self-contained human habitat, and hence will prove useful for the negotiation of Mars by explorers in the later future. Another benefit from the course of lunar missions is the furtherance of knowledge they will bring regarding the psychological and physiological effects on astronauts of long-term small-space confinement, increased levels of solar radiation, and reduced gravity. As such, lunar missions will prove complimentary to Martian ones.
With current technologies, spaceflights to Mars take approximately six months, with no capacity for return flight. However, a now-discontinued rocketry endeavor, “Project Orion,” was developed by NASA that proposed an atomic-powered rocket, theoretically capable of performing a 125-day round trip to Mars with a 100 ton payload. Such advancement in space travel technology would be instrumental in the opening of a Martian frontier.
Environment simulators, such as the MESCH (Mars Environmental Simulation Chamber) constructed by Jensen, et al, provide numerous research opportunities for future potential Martian conditions. In the MESCH, a carousel of cylinders is exposed to synthesized Martian pressure, temperature, atmosphere, and radiation. Such simulators are typically used for microbial cultures, testing the ability of various organisms to potentially survive in the Martian climate. Experiments utilizing Mars environment simulators like the MESCH have revealed a great deal of knowledge regarding terrestrial organisms and Mars. One study revealed that some photosynthetic microorganisms could survive Martian pressure, radiation, and atmospheric composition, for instance. Such knowledge will be beneficial to future terraformation projects on Mars.
Discussion
Mounting interest and development in the field of extraterrestrial exploration and colonization is turning speculation about Martian living into a potential reality whose practicality is fast approaching. At present, both NASA and ESA (the European Space Agency) have manned Mars flights as future goals, but project their enactment at about 2050: almost as long from the now as from the beginning of spaceflight to the present day. However, with the synergistic application of various technological and scientific advancements, some speculate a much sooner achievement not only of manned trips to Mars, but of the establishment of human colonies, possibly even capable of self-sustainment.
In “Astrobiology and the Human Exploration of Mars,” Paul Davies presented an opinion that the current “over-safety concerns” have resulted in a “culture of stagnation,” and advocates that space programs “get back to the exploration spirit and willingness of taking risks that was so prevalent during the time of Columbus, Darwin, and Amundson….” He suggested that instead of waiting for a time when sufficient technologies were developed for safe two-way travel between Earth and Mars for astronauts, that one-way missions are much more feasible, and that explorers should be willing to travel out to Mars without expectation of return. This would mean either a consistent flow of resupplying missions, or the establishment of some sort of sustainable habitat on arrival, possibly requiring some level of Martian terraformation.
Terraformation has recently passed from the realm of science fiction into a relatively practical reality. The southern ice cap of Mars contains much carbon dioxide, and several methods have been proposed to melt the ice cap, which would result in both the reformation of oceans, as well as a warming greenhouse effect and increased atmospheric pressure. Potential methods to melt the polar ice include subsurface nuclear blasting, pummeling via piloted asteroids, or the construction of an aluminum orbital solar mirror. Added to this, the fact that some microorganisms have demonstrated the ability to survive in simulated Martian climates means that there is a heavy potential for constructing a sustainable ecosystem on Mars.
Further, if the atomic rocket technologies developed under Project Orion were to be implemented, the necessity of one-way Martian missions could eventually be superseded. Earth-Mars travel time could then decrease to as few as four weeks both ways. Resources and personnel could be transported to and from the Martian surface at rates much quicker than those projected using current rocket technology, and Martian samples could be returned to Earth for study, furthering astrobiological and astrogeological goals.
Though it is still considered a far-off goal by many of those involved, recent and current technological and scientific endeavors have created a potential for Martian colonization in the relatively near future. The proper synergy of developments in astrobiology, rocketry, robotics, and human environment construction may open the door to a new chapter of human advancement. Humanity may quite soon find itself to no longer be a solely Earth-bound civilization.
Resources:
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Farmer, Jack, and David Des Marais. "Session 29. The New Mars: Habitability of a Neighbor World." Astrobiology 8 (2008): 431-36.
Jensen, Lars L. "A Facility for Long-Term Mars Simulation Experiments: The Mars Environmental Simulation Chamber (MESCH)." Astrobiology 8 (2008): 537-58.
Levine, Joel, and James Garvin. "Session 5. Astrobiology and the Human Exploration of Mars." Astrobiology 8 (2008): 310-12.
Sakon, John J., and Robert L. Burnap. "An analysis of potential photosynthetic life on Mars." International Journal of Astrobiology 5 (2006): 171-80.
"Stephen Hawking calls for Moon and Mars colonies." New Scientist. 05 June 2009 <http://www.newscientist.co
Wilcox, Brian H., Todd Litwin, Jeff Biesiadecki, Jaret Matthews, Matt Heverly, and Jack Morrison. "ATHLETE: A Cargo Handling and Manipulation Robot for the Moon." Journal of Field Robotics 24 (2007): 421-37.
Zubrin, Robert M., and Christopher P. McKay. "Technological Requirements for Terraforming Mars." Madasafish. 05 June 2009 <http://www.users.globalnet
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