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The second part in a three-part series of the unarchival of my old VASTS papers.

Abstract

Space exploration is a dangerous profession, not only is space a naturally hostile environment, but there are additional elements that must be considered in the context of a Martian mission. The pervading risk in space exploration is radiation, any particle containing energy on the electromagnetic spectrum. Radiation can affect the human body through causing cancers and interfering with cellular functions. The microgravity environment is another hazard that is inherent in space travel. Due to the lowered amounts of gravity experienced in a Martian mission, relative to the Earth, the body will undergo changes to acclimate itself. This includes a weakening of the cardiovascular system, a decrease in bone density, and a decrease in muscle mass. These changes must be reverted in the presence of gravity requiring rehabilitation periods built into the mission duration. The final hazard is crew selection. Desiging a process to promote diversity, cohesion, crew performance, and a resistance to groupthink is a difficult challenge. Crew selection is possibly the most intensive of these hazards as it is the factor that can determine whether the mission succeeds or fails.

Introduction

Christopher Columbus is popularly known as the discoverer of the Americas. Although it is now known that other explorers had reached America previously, such as the Vikings. Although Columbus alone holds the title, his discovery would not have been accomplished without effort made by himself, and other explorers, to overcome the danger inherent in transatlantic crossing during those times and push forward with their exploration. Explorers, such as Christopher Columbus, braved the elements, months in cramped quarters, poor hygiene, and, with the rudimentary navigation systems at the time, the very real possibility of getting lost. Yet, without the overcoming of these risks, we would not have discovered America as early as we did nor colonize it as early as the 1500s. We face a similar situation nearly 500 years later with the advances made in recent years in space exploration technology. By 1957, the Soviet Union launched the “first satellite, Sputnik, into space” (National Archives, 2016). By 1960 the Soviet Union had launched the “first living beings” (National Archives, 2016) into space followed by the first man, Yuri Gagarin, in 1961. The “first spacecraft to land on the moon” (National Archives, 2016), Luna 9, reached the moon in 1966. But it was not until 1969 that Neil Armstrong and Buzz Aldrin became the “first men” (National Archives, 2016) on the Moon. In 12 years, we went from next to nothing to landing the first human beings on the nearest celestial body. But these advances came at a steep cost, including the deaths of “Gus Grissom, Ed White, and Roger Chaffee” (National Archives, 2016) and later on the entire Columbus crew.

If the exploration around the horn of Africa is the modern-day equivalent of landing on the Moon, the transatlantic crossing is the equivalent of traveling to Mars and beyond. Similarly, we must assess the hazards of a space journey and do our best to prepare and combat for these hazards. Enabling astronauts to enter space knowing that the utmost precautions are taken to protect them against their hazardous environment. The primary hazard within space is the presence of radiation. On Earth, we are protected by our magnetic field that surrounds both “the Earth and the Earth’s atmosphere” (National Aeronautics and Space Agency [NASA], 2008). But as we leave the Earth’s atmosphere, we lose this protection until we exit the magnetic field and lose all shielding against any space radiation. All other rocky, interior planets have a Magnetic Moment of “0.0007” (Colorado University, n.d.), "<0.0004” (Colorado University, n.d.), and “<2.5 x 10-5” (Colorado University, n.d.) for Mercury, Venus, and Mars respectively. While the Earth has a Magnetic Moment of “1” (Colorado University, n.d.) significantly larger and offering far greater shielding than other rocky planets. The next hazard of space travel is the exposure of the human body to a microgravity environment. Due to the lack of gravity, the human body experiences drastic changes. These changes include “a reduction in muscle mass of up to 37%” (Fitts, Riley, & Widrick, 2001) requiring extensive muscle rehabilitation upon return to Earth. The final issue in space exploration is the selection of a crew. The crew is one of the most fundamental parts of the mission therefore, crew selection must take a high importance in the overall scope of the mission.

Radiation

One of the largest hazards that astronauts will experience in a non-Earth environment is radiation. Radiation refers to energy that is transmitted through the “form of rays, electromagnetic waves, and/or particles” (NASA, 2008). This radiation refers to the majority of the electromagnetic spectrum ranging from radio waves, with a wavelength “1 meter and greater,” (NASA, 2008) to gamma rays with wavelengths of “10-12 and smaller” (NASA, 2008). These waves are made up of photons that possess a dual nature of both wave and particle and are able to travel through “empty space as well as through air and other substances” (NASA, 2008). Higher energy photons, or waves, have shorter wavelengths, while lower energy photons have longer wavelengths and have a greater “potential for biological harm” (NASA, 2008). This radiation can originate from man-made devices such as “microwaves, cellphones, and diagnostic medical applications such as X-rays…radio transmitters, light bulbs, heaters, and gamma ray sterilizers” (NASA, 2008) as well as natural elements such as “radioactive elements within the Earth’s crust, radiation trapped in Earth’s magnetic field, stars, and other astrophysical objects”. The primary source of Earth based radiation is the Sun. The Sun emits energy at all wavelengths of the electromagnetic spectrum with a concentration in the “visible, infrared and ultraviolet” (NASA, 2008) portions of the spectrum. These steady emissions are accompanied by “solar flares and Coronal Mass Ejections” (NASA, 2008) that release energy into space in the form of “x-rays, gamma rays, and… solar particle events” (NASA, 2008), which all contain the highest energies on the Electromagnetic Spectrum. Although the Earth protects us against radiation with a magnetic field that surrounds both “the Earth and the Earth’s atmosphere” (NASA, 2008), as we increase in altitude and leave the Earth, the amount of radiation we are exposed to drastically increases.

There are two primary forms that all radiation affecting space travel falls into: ionizing and non-ionizing radiation. Non-ionizing radiation includes traditional radiation that is found on Earth including “radio frequencies, microwaves, infrared, visible light, and ultraviolet (UV) light” (NASA, 2018.a). Ionizing radiation encompasses “alpha particles, beta particles, gamma rays, x-rays, and galactic cosmic radiation (GCR)” (NASA, 2018.a). Of the two, ionizing radiation is the more dangerous one due to its ability to “move through substances and alter them” (NASA, 2018.a). As this passage happens, the ionizing radiation can ionize atoms “in the surrounding material” (NASA, 2018.a). Of the forms of radiation that composes ionizing radiation, GCR poses the greatest threat. GRC originates from both within and without “our Milky Way galaxy” (NASA, 2008) composed of an atom’s “nucleus moving at an incredibly high speed” (NASA, 2008). This form of radiation is formed by cosmic rays that are accelerated within the “magnetic fields of supernova remnants” (NASA, 2008). Eventually, these rays gain enough energy to escape “the remnant” (NASA, 2008). GCR particles are composed of “85% hydrogen, 14% helium, and about 1% high-energy ions” known as HZE particles” (NASA, 2008). These HZE particles have significantly greater power, penetration, and “potential for radiation induced damage” (NASA, 2008). Although GCR does not pose a high-risk to astronauts on the ISS due to the Earth’s magnetic field, it poses a problem in journeys to the Moon and beyond.

Radiation is measured with four factors in mind including “the magnitude of radioactivity of the source, the energy of the radiation itself, the amount of radiation in the environment, and the amount of radiation that is absorbed” (NASA, 2008). Therefore, not all types of radiation are equally damaging, some forms of radiation may be more damaging to biological systems than others. Another factor when considering the effects of radiation are the differences in ionizing and non-ionizing radiation. The value for the dose equivalent (Sv) is the measure of radiation’s biological affect and is calculated by the “’absorbed dose’ multiplied by a ‘radiation weighting factor’” (NASA, 2008). The dose equivalent is centered around x-rays and gamma rays making those forms of radiation have a dose equivalent value of 1. Alpha rays “cause 20 times the damage” (NASA, 2008) of x-rays and gamma rays and therefore have twenty times the radiation weighting factor and therefore, a twenty times larger dose equivalent. Radiation limits are “0.0036 Sv” (NASA, 2008) per year for the typical average person but up to “0.05 Sv” (NASA, 2008) per year for those that work with radioactive materials and up to “0.05 Sv/year” (NASA, 2008) for astronauts “in low-Earth orbit” (NASA, 2008). These dose limits are based on an “maximum 3% lifetime excess risk of cancer mortality” (NASA, 2008) therefore, older astronauts are typically allowed higher exposure limits than younger astronauts. Currently, astronauts on an 8-day mission in Earth orbit at 460 km will receive “5.59 mSv” (NASA, 2008), a 9-day mission to the moon will receive “11.4 mSv” (NASA, 2008), an 87-day mission in Earth orbit at 473 km will receive “178 mSv” (NASA, 2008), and a 6-month mission orbiting the Earth at 353 km will receive “160 mSv” (NASA, 2008). But, astronauts on an estimated 3-year Mars mission will receive “1,200 mSv” (NASA, 2008) or 1.2 Sv, a significant amount of radiation.

On such a 3-year Mars mission, it is estimated that “about 30% of cells in the body” (Setlow, 2003) will be affected by HZE nuclei with 10 to 28 protons and that “all cells” (Setlow, 2003) will be traversed by HZE nuclei with 3 to 9 protons resulting in “numerous ionizing events” (Setlow, 2003) within the cell. In addition to damage to the cells, radiation can also cause damage to the immune system. HZE events can cause further complications through a bystander affect where cells not directly affected by radiation can be affected by “neighboring cells that have been hit” (Setlow, 2003) by radiation. The dose of radiation to the effect seen in the cells may not even have a linear relationship with even a “concave downwards” (Setlow, 2003) relationship indicating greater damage at lower doses of radiation than at larger doses of radiation. But radiation is a problem that is primarily experienced in transit. At the end of most space travel is a planet that possess its own magnetic field. From studies by the Lunar Prospector mission, it has been found that some areas of the Moon “have a weak magnetic field” (NASA, 2008). Although these magnetic fields are not as strong as the Earth’s, they are able to “deflect small amounts of radiation” (NASA, 2008). Mars has similar regions that express a stronger magnetic field than the rest of the planet. But, due to the lack of an atmosphere on both bodies, the radiation shielding is minimal and requires greater precautions to reduce experienced radiation to a safe level.

Methods to address radiation come in two forms: operational countermeasures and engineering countermeasures. Operational countermeasures are mission-related parameters that can be manipulated to reduce radiation, including limiting how long a astronaut can be “a radiation worker in space” (NASA, n.d.), assigning “appropriate mission lengths” (NASA, n.d.), and creating a “radiation safe haven” (NASA, n.d.). Engineering countermeasures are the use of “hydrogen rich shielding” (NASA, n.d.) such as polyethylene and the creation of a “insulating layer of lunar soil (regolith) or water” (NASA, n.d.). Radiation at the destination, such as the Moon or Mars, can be reduced in two processes. The first process is selecting materials for bases that have anti-radioactive properties. The second process is taking advantage of natural geologic features that can directly combat radiation. As mentioned previously, extra-terrestrial bases could have high concentrations of polyethylene around crew quarters and other high-occupancy areas. Additionally, the entire base could have metal shield or even a water ice shield as hydrogen can readily block cosmic rays consisting of “mostly protons” (NASA, 2015). But these strategies require extensive financial investments due to the added cost of transporting a more complicated habitat. Another strategy is utilizing resources already present on extra-terrestrial surfaces. This includes the burial of a habitat beneath the regolith of a foreign body or utilizing weaker magnetic fields present on Mars and on the Moon. In terms of geologic features, the Martian surfaces possesses lava tubes that offer “protect[ion] from ultraviolet radiation” (Daga et al., 2013) other similar geologic features could be of interest on other planets. But utilizing resources on the planet’s surface requires extensive assessments of resources present on the body’s surface, limiting both the amount of materials that can be extracted as well as the efficiency of the materials used for shielding. In a similar vein, blocking radiation in transit poses similar issues. Although larger, and therefore heavier, radiation shielding can be launched on the spacecraft, the cost of significant radiation shielding could cut into other portions of the mission, limiting the scope and duration of the mission. One form of countermeasures that addresses both radiation in-transit and on the surface are dietary countermeasures. Dietary countermeasures are “foods or drugs” (NASA, n.d.) that can mitigate ionizing radiation. Dietary countermeasures include both natural nutrients as well as drugs. Nutrients include “nutrients that prevent radiation damage” (NASA, n.d.), “antioxidants” (NASA, n.d.), “pectin fiber” (NASA, n.d.), and “omega-3-rich fish oils” (NASA, n.d.). These can prevent damage by “soaking up radiation produced free-radicals” (NASA, n.d.) as well as increasing the removal of “radioactive substances…from the body” (NASA, n.d.). Of the methods to address radiation, a dietary approach appears the most feasible due to the relative low constraints in comparison to engineering or manipulating the mission for lower radiation exposure.

Microgravity

Unlike the Earth, most of space does not have a similar gravitational pull. Within empty space, very low amounts of gravity are felt. This condition of gravity is known as microgravity. Even on other bodies, there is a lower gravitational pull than that of the Earth. The gravity of Mercury, Venus, the Moon, and Mars are only “0.378” (NASA, 2018.b), “0.907” (NASA, 2018.b), “0.166” (NASA, 2018.b), and “0.377” (NASA, 2018.b), respectively, of the Earth, all far lower than the gravity the Earth offers. Only Venus’ gravity compares to the Earth’s but with its high temperatures and pressures, it is an unlikely candidate for future human exploration. In free space, one always experiences the pull of gravity. But, the force from this gravity is very low due to the distance between the larger gravity producing object and the relatively low mass that a spacecraft, and the astronauts within, possess. An interesting phenomenon is the feeling of weightlessness experienced in the ISS within Earth orbit. Although astronauts on the ISS are within the Earth’s gravitational field, they experience none of it because “they are in free fall” (NASA, 2012). This is because in the ISS, the crew, spacecraft, and all the other objects are falling around the Earth experiencing weightlessness. This is done by the spacecraft orbiting the Earth so that its fall “matches the curve of the Earth” (NASA, 2012).

In weightlessness, the body experiences “space motion sickness” (Virginia Space Grant Consortium [VSGC], n.d.a) the condition where the body has to relearn how to process spatial cues. This in part is due to the lack of a force pulling on the fluid within the canals of the vestibular organ. This lack of a cue on the direction of gravity confuses combined with conflicting signals from the “muscles; joints; [and] the senses of touch and sight” (VSGC, n.d.a) all combines to contribute to “space motion sickness” (VSGC, n.d.a). But this condition subsides after “a few hours or days” (VSGC, n.d.a) once the astronaut acclimates. The more important effects of a microgravity environment are the “deconditioning of physiological systems” (VSGC, n.d.a) such as the cardiovascular system. On Earth, the heart and the surrounding organs are acclimated to a high-gravity environment that the body has to work against to provide circulation. In space, this resistive force is absent leading to the drastic decrease of heart rate, output, size, and “blood volume regulation” (VSGC, n.d.a). Another result of the reduced gravity is its affect on “the musculoskeletal system” (VSGC, n.d.a). The loss of the resistive force applied by the Earth’s gravity results in the “loss of calcium, nitrogen, and phosphorus” (VSGC, n.d.a) as well as “decreased bone size and volume” (VSGC, n.d.a). According to a study on the Mir station, “1.2% of bone mass” (VSGC, n.d.a) in the lower hip and spine is lost per month due to microgravity. Further, astronauts experience “weakened reflexes, and decreased tolerance for physical work” (VSGC, n.d.a) a serious problem when astronauts are experienced to work on a Lunar or Martian surface base after months in transit.

More importantly, the time spent in the microgravity environment results in a “reduction in muscle mass of up to 37%” (Fitts, Riley, & Widrick, 2001), “the loss of bone” (NASA, n.d.b), “change in cardiac performance” (NASA, n.d.b), and “a changing nervous system” (NASA, n.d.b). Upon return to the Earth, the body requires a “45-day ‘reconditioning period,’ to build up bone and muscle strength” (Wall, 2016). Upon return to any gravity, the astronauts will experience balance disorders that affect the “central nervous system” (NASA, 1998) including functions that are dependent on the central nervous system including “hand-eye-hand coordination, posture, balance, and gait” (NASA, 1998). In terms of sleep, the astronauts experience a desynchronization of the “circadian pacemaker” (NASA, 1998). The loss of sleep in microgravity can be the cause of a drastic decrease in performance in astronauts on missions. The microgravity environment also decreases orthostatic tolerance or the “ability of the cardiovascular system to supply the brain with enough blood to maintain consciousness” (NASA, 1998).

This problem is primarily transit related due to gravity being minimal in transit with a greater amount of gravity on the surface. A potential solution to addressing this problem is creating artificial gravity in the spacecraft. This could be created by including an “onboard centrifuge” (VSGC, n.d.a). The centrifuge could be spun to slowly acclimate astronauts to weightlessness and then restarted upon approaching the surface to conserve energy. In a non-energy-efficient manner, the centrifuge could be spun for the entire journey so that the astronauts never undergo space adaptation syndrome. But, the limitations to this solution are that a extremely large vehicle would have to be built that would also have the energy source to maintain the constant rotation. Additionally, only a small portion of the ship would be habitable as the area near the center would have increasing centripetal force differentials that may cause “rotational sickness problems” (VSGC, n.d.a). Another method to mitigating the affects of microgravity in-transit is the incorporation of exercise machines into the ISS and exercising into the astronauts’ routines. This would prevent the atrophy of the musculoskeletal system and some of the cardiovascular degeneration experienced in the microgravity environment. Limitations to this solution are the amount of time available to each astronaut to exercise, a variable that depends on the number of astronauts and the number of exercise machines. A greater number of exercise machines would result in a greater duration of time to exercise for each astronaut, but a lower number of exercise machines would require a smaller crew to enable each member to have sufficient exercise time. The number of exercise machines affects the launch weight and the cost of the mission. A surface solution is the inclusion of a rehabilitation program tailored for the Martian surface based off of the Earth’s rehabilitation program. This would be limited to the amount of time the astronauts have available beyond their own free time, time spent dedicated to the mission, and time to sleep. Another method of reducing the amount that microgravity affects surface activities is by increasing the duration of the surface mission. On Earth NASA utilizes a “45-day ‘reconditioning period,’ to build up bone and muscle strength” (Wall, 2016) by having a Mars mission significantly longer than the rehabilitation period, more time is spent on the surface when the astronaut is acclimated to Martian conditions.

Crew Selection

The integrity of the crew is essential to the success of the mission. A tight-knit crew breeds trust, friendship, and enables each crew member to perform to his or her maximum potential. The failure to select a compatible crew can result in discord and dissonance among the crew resulting in a less efficient performance from the crew and even the failure of the mission altogether. For a Martian surface mission, astronauts must be selected for their “ability to work with others under stress” (VSGC, n.d.b). And in team leader selection, leaders must be able to cater to all crew members, exacting the maximum efficiency from all crew members. Further, they must have the capacity to support crew members in an emotional sense. An extended mission to Mars will entail that the crew will be living in confined quarters and must be selected so that “quarrels do not break out among them” (VSGC, n.d.b). In a more micro sense, the size, occupations, genders, and nationalities of the group must also be considered when the crew is being composed. The dynamic of a small group will be significantly different from a larger crew, this factor is especially important when considering that the size of the crew effects the extent of the mission, the costs involved in the mission, and the length of the mission. In smaller crews the selection process must be extremely selective as the occupations “covered” by the crew must encompass all the required subject fields for the mission. Conversely, in a large crew many masters from distinct fields may be selected rather than people with experience in many fields. Gender and nationality-wise, the crew must be selected to have maximum diversity so that the decision-making process receives varying inputs from all members rather than similar inputs from all members and leaving the crew susceptible to group-think. Leadership is essential to any crew dynamic; the leader is expected to “organize, direct, and coordinate followers” (Connors, 1985) as well as “maintain harmony and stability” (Connors, 1985). But this leadership must be dynamic, as one person may not be able to perform all these responsibilities all the time, therefore leaders must be selected situationally. Although these members may be leaders, the decision-making process must be autocratic as well. Having subordinates offer contributions to the decision-making process can prevent the leader from finding it “increasingly difficult to lead” (Connor, 1985). The demands placed upon the leader will be especially heavy due to both the magnitude of the mission as well as the small-scale group that will be led. The Martian mission will be subject to “stringent technical requirements” (Connor, 1985) as the mission will be completed in a hostile environment. As the mission progresses and the distance from Earth increases, the leader’s responsibilities will increase. Because the distance from Earth will resulting in lower communications with Earth-based decision making. As the leader, they will be expected to “be shrewd judges of human nature” (Connor, 1985) and display “superior interpersonal skills” (Connor, 1985). The failure to fulfill these responsibilities can pose a serious risk to a isolated or confined group such as that of a Martian mission. In a series of fallout-shelter studies, a passive shelter commander was reported to have caused “a general lowering of standards of behavior” (Connor, 1985). Conversely, a good leader can “prevent factionalism and ease group members through troubled relationships” (Connor 1985).

Cohesiveness refers to the group’s collective sense of “energy and strong sense of purpose” (Connor, 1985) as well as members that express “a strong sense of liking” (Connor, 1985) for one another. One of the most efficient methods to promote this cohesiveness is to introduce goals to the group. The presence of group goals helps allow for members of the crew to “suppress their differences in the interest of group goals” (Connor, 1985). Therefore, by instilling the importance of goals within crew members, differences between crew members will be naturally suppressed. Therefore, in the planning of the mission, the mission should be built around goals and have each of these goals clearly defined to maintain the sense of solidarity within the group. Beyond a goal-based approach to maintaining cohesiveness efforts could be taken in crew selection to reduce interpersonal conflicts. This includes training astronauts in “task and socioemotional training…to help minimize or contain interpersonal conflicts” (Connor, 1985). Another factor that affects crew cohesiveness is the manning theory that implies that the size of the crew relative to the workload affects the “level of energy” (Connor, 1985) the crew will apply to the task. When the mission is adequately staffed, there will be a good match between the “number of people available…and the situation’s technical and social demands” (Connor, 1985). Under such conditions, the crew is neither rushed nor are “their abilities allowed to languish” (Connor, 1985).

Group performance is affected by “the knowledge and skills” (Connor, 1985) group members possess, “the amount of energy or effort” (Connor, 1985) the group members apply, and the “strategies or procedures” the group members follow in their tasks. By manipulating the composition of the group, varying knowledge and skills will be expressed. By selecting crew members with “complementary skills and interests” (Connor, 1985) after “careful analysis of mission requirements” (Connor, 1985), could result in a crew optimized to the mission. On the individual level, by assigning each crew member individual assignments that “provide the opportunity to use a variety of personal skills and abilities” (Connor, 1985), “involve ‘whole and visible’ pieces of work” (Connor, 1985), allow for initiative and discretion, and are structured to allow for the assessment of “his or her level of performance” (Connor, 1985).

Crew selection must transverse nationalities to promote diversity and lower the possibility of group think within the crew. But the crossing of nationalities can lead to “serious language difficulties” (Connor, 1985). On the Apollos Soyuz flight, American and Russian astronauts attempted to communicate with on another after “spending 1000 hr studying the language of the other” (Connor, 1985). But the level of proficiency experienced from both sides was “insufficient for communication on a typical flight” (Connor, 1985). Although the need for diversity is recognized, the need for proper and effective communication surpasses the need for diversity.

Groupthink is the process in which any group can make “bad or irrational decisions” (Seton Hall University [SHU], n.d.). Within group think, each member attempts to conform his or her individual opinions to that of the perceived consensus of the group so that the final decision is one that no constituent of the group agrees with. The primary drive for such a decision comes from the members’ “strivings for unanimity” (SHU, n.d.) overtake their notion to assess the situation and make a valid decision. Conditions that could promote group think are “insulation of the group, high group cohesiveness, directive leadership, lack of norms requiring methodical procedures, homogeneity of members’ social background and ideology, [and] high stress from external threats with low hope of a better solution than the one offered by the leader” (SHU, n.d.). As a Martian crew will be subject to the first, second, third, and fourth conditions, the Martian crew must be selected to prevent against falling to group think.

The selection of a crew is paramount to the success of the mission as it is one of few factors that can directly lead to the failure of the mission altogether. Therefore, factors that affect crew performance and are affected by the composition of the crew must be addressed. As crew selection is a problem that affects the entirety of the mission from training to return, it must be the foremost problem for any mission organizer. Selecting a good leader is the first issue that must be addressed when composing the crew. This leader must be able to make decisions under pressure but also be able to maintain a sense of cohesion with his or her crewmembers. By having a leader with the interpersonal abilities to do so, the crew is more easily able to perform. To properly engage both cohesiveness and performance, the crew must be selected with careful analysis of both the members needed for the mission and the skills that each member requires. For example, if a Martian mission is to construct the Martian base, sufficient astronauts must be selected to build the base as well as have the skills sufficient to construct the base including electrical engineering, physics, architects, etc. Although a diverse crew would prevent against groupthink, the increasing differences among the crew, specifically the language barrier, would decrease communication among the crewmembers. Therefore, a crew must be selected that is diverse enough to prevent against group think yet maintain sufficient communication. Crew selection will focus on crew members suitable for for “a seemingly complete break from the Earth and the protective social matrix in a small, isolated, closely confined container with few companions” (Sgobba, et al., 2018), making psychological strength a priority, “intense motivation for the project” (Sgobba, et al., 2018), “have a strong ability to cooperate” (Sgobba, et al., 2018), and “win the trust and confidence of associates” (Sgobba, et al., 2018).

Danger Assessment

Of the preceding hazards, crew assessment is quite possibly the most dangerous and most pertinent to the success of the mission. The failure of the crew can lead to the failure of the mission altogether. Radiation is dangerous to the crew as it exposes the crew to unsafe levels of radiation. This may lead to mutations and even cancers that would be extremely difficult, if not outright impossible, to treat in a Martian mission. Although radiation poses a risk to each individual astronaut, it does not pose a large risk to the success of the mission as a whole as it can be mitigated through the use of shields, geologic structures, and dietary measures. Although radiation does pose a threat to astronauts its lack of threat to the overall mission as well as its relatively simple mitigation solutions make it the least dangerous of the hazards listed above. In a similar vein, the microgravity environment that the astronauts are exposed is less harmful to the astronauts than radiation but, poses a problem to the mission overall. The microgravity environment can be overcome with a rehabilitation period as seen in previous astronauts that have returned to the Earth. But the only place where the rehabilitation period becomes a problem is when the mission duration must be extended so that astronauts acclimating to the Martian gravity have enough time to recuperate. This extra time required for the astronauts to acclimate to the new gravity slows down the mission but does not lead to the catastrophic failure that a poorly meshed crew can cause. As seen in the decision-making practices made in the explosion of the Columbia, the presence of groupthink caused by poor crew selection is a very real risk that can lead to the eventual failure of the mission. By selecting a crew that is able to resist group think as well as fulfil the other portions of the mission can help guarantee the success of the mission. But the selection of the Martian crew will be a difficult process forcing mission coordinators use utmost scrutiny when analyzing a candidate.

Conclusion

A manned Martian mission to establish a base on a planet that can be utilized as a jumping off point for future space exploration and provide a testing grounds for space technologies is essential to the advance of the human race. A manned mission to Mars would be able to accurately assess the potential of the Martian regolith for future commercial use, assess the life-capabilities of Mars, and set up the Martian base. But the risks posed by radiation, a microgravity environment, and crew selection are all hazards that must be considered and mitigated before the mission. Radiation poses a risk through its destructive property to the human astronauts that are exposed to unsafe levels of radiation over the course of the Martian mission increasing the astronauts’ risk of cancer. The microgravity environment can lead to the weakening of the astronauts’ cardiovascular system as well as the musculoskeletal system. These atrophications require rehabilitation periods that can affect the time-scope of the mission, affecting both the scope and duration of the mission. The final, and most important risk is crew selection. Crew selection can spell disaster or success of the mission overall due to the initial selection of the crew changing the crew’s susceptibility to groupthink, non-cohesiveness, and lack of leadership.

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Appendix

Assessment of Risks Posed to Astronauts in Space Exploration

The danger posed by space exploration is a serious one that has received ever more attention over the years as our understanding of space has developed. One of the most pervasive risks of space exploration is the exposure of astronauts to greater amounts of radiation in space than that on Earth. Although this radiation does pose a serious threat, the engineers at NASA have taken precautions to construct spacecrafts out of anti-radiation materials so that astronauts are sufficiently shielded from space radiation.

Microgravity is another space hazard that has gained more attention as more and more research has been conducted in microgravity environments. These environments, as experienced on the ISS, can lead to a weakening of the heart, decrease in bone strength, and a loss of muscle mass. Astronauts that return from microgravity environments must undergo physical rehabilitation to regain the strength to function in the Earth’s higher gravity environment. In a long duration Martian mission, astronauts will experience significantly larger decreases in bone strength and muscle mass, elements that will require rehabilitation upon the Martian surface. But these problems can also be addressed in-transit through allocating time for astronauts to exercise and reverse some of the effects of the microgravity environment.

The crew selection process is the final and most important risk that can be posed to space travel. Members of space exploration crews must be selected to be able to handle long durations in isolated environments with 4-8 other people. The selection of a proper crew and the administration of proper training to a diverse crew who can understand and carefully analyze problems to make careful, educated decisions will drastically increase the efficiency and chances of success of the mission.