Spaceflight is one of the most outstanding achievements of humankind. Its reputation as one of the loftiest ambitions can be mainly owed to the vast amount of material in popular culture and children’s shows. Particularly, movies like Star Trek or Star Wars continue to capture the general public’s interest and increase their fascination with outer space. However, these television shows portray reality somewhat inaccurately. Behind each spaceflight is an astronaut agonizing over the changes they are experiencing outside the Earth’s gravitational pull. Therefore, to achieve humanity’s future of residing on a different planet, it is imperative to study and resolve the problems encountered in human physiology due to changing conditions. In this paper, the discussion will primarily be focused on issues the human body faces in outer space and how these problems will be solved. Aside from that, this paper provides insights on how human civilization can successfully colonize our neighbor planet – Mars.
Changes in the human body begin when the individuals are no longer subject to Earth’s gravitational pull, resulting in a significant decrease in the constant forces that come with it. The first organs that will be affected by these changes are the bone and the muscles. Because the body is now under the influence of microgravity, bones no longer need to oppose the forces of Earth’s gravity, and the astronauts then experience a loss in bone density. The reason for bone degeneration is that osteoclasts, the bone-breaking cells, are more active when not acted upon by a mechanical stimulus; thus, the rate of bone resorption exceeds that of bone formation, leading to bone density loss (Stavnichuk et al., 2020). Conversely, microgravity affects the spinal vertebrae, as well, by expanding it to about two inches of its regular length (Penchev et al., 2021). These complications often lead to osteoporosis in astronauts. Aside from affecting the bones directly, the lack of strong gravitational forces also affects chemicals involved in bone formation. Specifically, there is an observed significant increase in calcium excretion in astronauts, which infiltrate the blood to reach the kidneys to form calcium stones. Similar to this problem, muscles experience changes due to the absence of gravitational forces that once acted to strengthen them, and the most prominent difference here is muscular atrophy. This problem was believed to be caused by a significant decrease in protein synthesis in space (Vandenburgh et al., 1999). Muscular atrophy and bone density reduction increase the risk of tearing the ligaments and the onset of other ailments under strenuous activities; thus, these must be adequately addressed if one wishes space travel to be the norm in the future.
Aside from the bones and tissues, escaping Earth’s gravitational pull also causes problems in the fluid inside the body, inconveniencing the human body’s organs. Typically, gravity pulls body fluids towards the lower part of the body; however, there is an equal dispersion of liquid throughout the body in the case of an individual residing outside our planet. This reason explains why astronauts often appear puffy than usual. One problem caused by this phenomenon is the increasing pressure against the brain due to the excessive amount of cerebrospinal fluid acting upon it (Krupska, 2017). The body removes plasma and RBCs in response to the increased fluid levels, resulting in anemia (Smith, 2002). Aside from the mentioned, astronauts’ eyeballs flatten because of increased body fluids; thus, they often experience farsightedness in space. Apart from the effects of body fluids, the movement itself through space is proven tedious by many. One particular case is the impairment of the ear’s vestibular system, which causes frequent motion sickness. Furthermore, T-cell inactivation is commonly observed outside the planet; hence, the immune system is somewhat weakened (Akiyama et al., 2020).
From the examples mentioned above, it is evident how traveling outside the planet takes a toll on the anatomy and physiology of an individual. Hence, these issues must be addressed accordingly. In fact, the National Aeronautics and Space Administration (NASA) has a Human Research Program (HRP) that studies the effects of living in space on the human body. First, for problems associated with bone resorption, it is suggested that the individuals perform weight-bearing exercises. Aside from that, they are recommended to take drugs against osteoporosis and Vitamin D supplements (Feinzeig, 2014). It is recommended that the individuals take calcium supplements to prevent calcium stones from forming, as well. Recently, researchers studied new methods of removing kidney stones while in space, which were done using ultrasound technology (Robinson et al., 2018). For muscular atrophy, it is recommended that the astronauts perform exercise regularly and drink growth hormone supplements. Aside from the mentioned, researchers suggest that better in-flight training and orthostatic blood pressure control stimulation can help combat the body fluid problems encountered by these individuals and train their bodies against motion sickness (Watenpaugh, 2001). Taking commercially available medications may also help against the mild anemia they experience and strengthen their acquired immune system.
Once these issues on the physiological effects of space travel have been resolved, the people’s attention should be focused on the potential colonization of neighboring planets, namely Mars. However, several barriers to planetary settlement prevent this from easily being achieved. For one, gravity differences remain a problem for humans. Furthermore, one must consider the physiological needs of man. Of course, the primary concern would be long-term food procurement since man requires around 2,200 to 2,800 calories a day to be considered healthy (Osilla et al., 2021). The problem here is that the soil on Mars is unfit to grow life; thus, there is great difficulty producing crops. Additionally, the inability to grow plants would mean that livestock is unable to eat; hence, it would be challenging to grow animals commercially. Aside from problems associated with food production, Mars also suffers from a lack of water sources. This absence of significant water sources is a massive impediment since man can only survive at least three days without water (Popkin et al., 2010). Aside from the mentioned, air quality is also a known barrier to a successful Martian settlement. Martian air is composed mainly of carbon dioxide; therefore, humans will only be suffocated upon encountering this atmosphere (Rafkin & Banfield, 2020).
Apart from man’s physical needs, factors such as the health of individuals in the long term remain an unsolved problem. First, childbirth’s potential events outside Earth still are a mystery for many; however, many studies are underway (Proshchina et al., 2021). Reproduction is essential to bringing forth the next generation of Martians that will be situated on the planet. Furthermore, differences in the properties of Mars, such as the magnetic fields, poles, etc., may pose discrepancies in the functioning of current technology when adapted to this neighboring planet. Lastly, mental and emotional factors may come into play when the first Martians begin residing on Mars; thus, this must be considered to bring about a fruitful society.
To succeed in establishing a human settlement on the planet Mars, each problem must be addressed accordingly, with meticulous detail. The leading solution I had conceptualized to counter most of the issues would be constructing a controlled environment, such as a dome. In this environment, the gravitational pull is simulated to mimic Earth’s forces; hence, problems associated with gravity will no longer affect the people, and childbirth can proceed as usual. Secondly, within this controlled environment, the introduction of Earth’s researches, such as soil, can solve problems associated with food for the general population. Aside from that, within the dome, oxygen and water will be generated continuously by chemically converting the carbon dioxide from the surrounding air into oxygen and carbon monoxide. Water can be produced synthetically using oxygen. We can then sequester carbon monoxide through a device so it may not cause harm to the Martian environment. Lastly, within the dome, establishing a distinct magnetic field that is compatible with Earth’s devices will allow the usage of current technology. The only drawback of this solution is that it requires much effort and maintenance to help society function for a very long time. Second, I would like to consider terraforming, a solution favored by many scientists for the planet. Through terraforming, the Martian atmosphere, temperature, and ecology can be altered to suit the needs of the settling population. This change will allow a natural environment that is “Earth-like.” Similar to the abovementioned, problems associated with the physical demands of man are dealt with accordingly. In fact, this is much preferred due to the reduction of maintenance efforts needed to sustain a working environment for the society. If possible, I would like to implement the dome environment first to carry out experiments. Subsequently, once humans have adapted to Mars, terraforming can begin and change Mars to be accessible to a more significant population of humans.
The future of space exploration and planet colonization is not bleak. Scientists are currently exploring many efforts to make the abovementioned possible. In this paper, I have discussed many barriers encountered presently in space travel and Martian colonization. I have also conceptualized potential solutions that can be applied for its success. Thus, I can conclude that these endeavors that will elevate humankind are within hands reach. Though it will be a difficult journey, I am confident that we will achieve these goals in the near future.
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