Human space travel has always fascinated humanity. Since cosmonaut Yuri Gagarin managed to travel into space in 1961, there have been numerous projects designed for space missions. There is no doubt that space exploration has continued to expand human knowledge. Sometimes in the past, NASA has come under harsh criticism for its high budgets. The exorbitant costs associated with exploring space have led some people to become pessimistic in the dream of exploring space. Apart from the financial costs, long term space travel has a huge impact on the human body. There are confirmed fears that space travel is a threat to human health and wellbeing due to the hazardous environment of space. Additionally, there are unique engineering challenges that affect the prolonged duration of space missions. However, with the advancement of aerospace technology in the second decade of the 21st century, long-term space travel in becoming, even more, a reality than a possibility. There is a renewed sense of optimism around astronauts that humanity is about to achieve a great fete in space exploration. Even though there are still some critical challenges in space exploration, long-term space travel is a very possible and attainable project with our current technology.
Human Limit
Space environment may not be conducive to human health, but there are numerous advancements that are promising to solve this challenge for long-term space travel. It has been confirmed that the human body goes through several changes while in an environment that has no gravity such as space(Kitmacher et al. 601). Ideally, without gravity, the human body loses the ability to hold internal body fluids. This causes the enlargement of the heart and other body organs. The corrective mechanism of the body responds by excreting excess body fluids leading to the loss of calcium, electrolytes, and blood plasma from the body(Zwart, Morgan, &Smith 218). The human body size also undergoes height changes. It has been shown that long-term exposure in space causes the body to grow by about two inches. The difficulties of traveling to space do not stop there as scientists have noted that the body becomes mildly disoriented(Stuster 213). What is even worse is that the body suffers from psychological changes alongside the physical ones. It is not uncommon for people who have been exposed to environment with no gravity to suffer from extreme depression and irritability. However, all these changes to the body are soon resolved once the body had with gravity.
The human limit to space travel is a huge challenge. Without gravity, some of the body muscles in the human body lose their functional significance. The process of muscle eutrophication occurs at a rapid rate. An astronaut who goes on a lengthy mission to space soon finds out that the affected muscles have lost their functional capacity after a month. The muscles lose the mass to function as expected and the astronauts usually find it hard to walk again(Clément, Gilles, & Reschke 26). To make it worse, long term space exploration has come to be strongly associated with extreme osteoporosis. That is, the human body progressively loses bone mass every month of approximately 2% per month. It is estimated that the accumulated bone loss by two years for an astronaut is equal to the bone loss of a 90-year-old adult(Orwoll et al. 1200). The astronauts are more at risk of deteriorated health once they are exposed to gravity again because their skeletal systems become too susceptible to stress fractures(Mader et al.250). It is speculated that after a long-term mission in space, the body could be so weakened that even an attempt to walk would cause breaks and fractures. There are still major doubts on whether the process could be reversed successfully.
The last major huddle that the human body needs to master to explore long-term space travel is radiation poisoning(Swenberg, Charles, Horneck,& Stassinopoulous 12). There is too much radiation from the sun that has the potential of causing gene mutation. This is because space lacks the protective shield of the atmosphere and the magnetic field. Therefore, space has an amount of radiation estimated to be around a thousand times greater than the one on earth(Durante, Marco, & Cucinotta 1245). There is an increased likelihood of suffering from severe cancer as well as radiation poisoning from long-term space travel. The huge challenge is that cell damage as a result of radiation exposure can be a source of severe internal body problems.
Financial Cost
Long term space exploration is a costly venture. Going by the tally of space shuttle programs in 2010, it was estimated that every planned flight would cost $1.6 billion. Since the inception of NASA, the agency noted that it has used over $190 billion on space shuttle missions (Rogers 23). Even as it celebrates just over three decades, it has to be noted that it has not come close to achieving its targets. Between 2015 and 2016, White House proposed a budget of $500 million boost for NASA for its planned mission to Mars. A separate mission to Jupiter required an estimated $18.6 billion budget(McCurdy). This is a nutshell of some of the projects that re-planned by NASA into deep space and their respective costs. There are additional costs required for building space systems where astronauts can travel to and from the International Space Station, a plan that needed $1.23 billion in 2015 up from $805 million. Building the International Space Station (ISS) is also an expensive venture because by 2011 the project had cost over $100 billion(Hsu). This shows that the cost of long-term space travel is a combination of numerous expensive factors.
The other huge challenges that face long-term space travel concerning finance is the cost it takes to float an object in orbit. Rinaldi (1100) cites that “Today it costs about $10,000 to get a single pound of mass into low earth orbit and a significant part of this cost is related to the design and production of the launch system.” It makes it even more costly to note that almost 40% of a single flight cost is taken up by the launch process. This means that the cost has to be reduced significantly to facilitate long-term space travel.
Other Challenges
The technology challenge affecting long-term space travel today cannot be ignored. Lin, Kun et al. (10180)cite that “space travel can present extreme environments that affect machine operations and survival.” This is because machines are sensitive to factors such as gravity, radiation, static discharge, temperatures, and propulsive forces.” Better machines are required to withstand the harsh environment in space. There are still numerous technical challenges that need to be solved today. To start with, there is a need to develop a laser propulsion system. Such a system would enable the space travelers to cover a large distance in space using better laser power. The disasters that befell Challenger and Columbia space shuttles were critical reminders of how critical it is important to have the right technology to guarantee human safety in space(Gibbs). More research and development is required to know the right design of spacecraft that can withstand space problems and still be capable of bringing back people to earth safely. So far, NASA has mostly focused on robotic missions that were significantly easier and lighter to take to space that people. What this shows is that there is still more to know about space to help scientists provide the right environment for long-term space travel. President Obama projected the will and need to have better-equipped spacecraft by 2025 that can withstand longer journeys in space. This is a projection that can be attainable if there are fewer budget cuts for NASA and more research and development is conducted.
Solutions
The harmful effects that long term space travel has on the health of travelers have to be solved for the space travel to be feasible. The scope of space-based medical care has to be improved to suit terrestrial care(Clément, Gilles, Bukley, & Paloski 121). If this is not possible, scientists need to mitigate the negative impact of space environments on human health. To this day, scientists are in the process of developing new treatments that will cure skeletal muscle problems caused by weightlessness in space(Mortazavi, Javad, Cameron, & Niroomand-Rad 1500). These are drugs that could stop the decay of bone material in an environment without gravity. However, the best improvement so far has to be the creation of artificial gravity. Artificial gravity has the potential of solving potentially all problems caused by lack of gravity in space. According to Spillantini (900), “artificial gravity can be created by investing in the design of a drum that revolves in circular motions. Its momentum would create artificial gravity.” However, the challenge that faces this solution is that the amount of energy that it would require would be enormous, compounding the engineering problems. Despite the obvious challenge of creating a suitable environment that can withstand the environment in space, scientists are optimistic that it is possible to protect astronauts from the harmful radiation of a long-term space travel(Mortazavi, Javad, Cameron, & Niroomand-Rad 1113). Lead has to been proposed as a potential protector from dangerous radiation. However, the challenge has been to incorporate just the right amount thickness of lead not to affect the thrust of spacecraft. As to whether this challenge can be solved today, the Chief Health and Medical Officer, NASA, opined that “if we decide to do something and we set our mind to it and put the resources behind it, we can be successful.” At least, optimism is high and scientists are in agreement that new designs of spacecraft that are enhanced with lead protector are feasible. Until this is achieved, a lighter shield of lead that protects space travelers from the harmful radiation will remain the best way to solve the problem.
The financial challenge can be tackled by involving the private sector more and proposing more budgetary allocations from the Congress. However, there is an agreement within NASA that the more research and development is required to improve space knowledge so that resources are channeled toward the right projects. NASA has been affected in the past by budget cuts which have stalled programs that were initially designed to develop spacecraft for long-term space travel(Johnson, Dana, Pace, & Gabbard 25). There is a need to step back and change the mode of technological investments for long-term space travel to be feasible. If there is sufficient funding, EDL (entry, descent, and landing) systems will be achieved for space missions. It is recommended that NASA should seek international partnerships to allow more groups to work together(Bilski et al.300). With international cooperation and sufficient funding, the challenge of developing modern propulsion systems will be achieved without much struggle.
Conclusion
It is important to note that space travel is faced with numerous challenges. However, it is also evident that decent research has been conducted to support advanced technology and make long-term space travel even more feasible. Space environment may not be conducive to human health, but there are numerous advancements that are promising to solve the radiation problem and skeletal issue. Space exploration is also a costly venture, but sufficient funds have been proposed toward NASA to complete certain projects that will make it easier for long-term space missions in the future. There is also a considerable effort toward research and development to clear some of the unknowns in space and enable the creation of better spacecraft. This shows that long-term space travel is possible and realistic. As scientists and engineers have noted, the right investments and support should make the dream of long-term space travel a reality sooner than later.
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