Space Exploration and Colonization Essay
Space Exploration and Colonization: Using Technology and Human Enhancements in our Race for Space Since the beginning of man’s existence on this earth, the night time sky has held awe and wonder. The questions of what may exist have long been pondered and are chronicled throughout the written history of our species. Technology and science allowed early scientists to prove the sun as the center of the solar system as well as many planets besides earth orbiting that very sun. It later allowed them to witness the stars as distant suns, each potentially holding planets which may, even if by a miniscule chance, hold life.
Dreams of man traveling into space and exploring the universe were simply that, pipe dreams without the technology to support them. However, technology has shown a way of catching up with our dream. Explorers had better ships and star navigation to discover the new world, the Wright Brothers learned the intricacies of powered flight and finally allowed man to leave the ground. In a very short amount of time, technically speaking, man has achieved the once impossible and not only traveled into space, but walked on the moon.
There are many reasons man has to explore the universe; natural resources, our natural exploratory nature, or seeking new life, man will eventually develop the technology necessary to make this a reality. Though moon walks and subsequent space stations are great achievements, ones never to be forgotten, the success of space travel has also raised a great many questions and concerns. These concerns raise disturbing questions as to whether man will ever achieve prolonged space exploration or colonization. The human body is a delicate machine which was built and designed through evolution to survive on the strict guidelines of this planet.
Things like atmosphere and gravity, along with our susceptibility to solar radiation will make it very difficult to achieve our goals. In addition, the propulsion technology now at our disposal is woefully inadequate to reasonably assume we could use it for prolonged exploration. Best estimates assume a space flight to Mars would be 7-9 months in duration one way, with a stopover period of 500 days or so in order to realign the planet for a return trip. Including the 7-9 month return trip, that would be approximately a 3 year trip. In this paper, I will discuss the problems this poses with the human body.
Bone and muscle loss from lack of gravity during travel, our need for atmosphere and the effects of its absence on our body, radiation and the pitfalls that poses. These are all issues which must be addressed in order to make space exploration and colonization a reality. In addition to discussing the dangers, I will also propose possible solutions given to us by some of the greatest minds and thinkers. These ideas may not all be conventional, but after all, humanity has been doing the unconventional our whole existence. The human body requires a delicate balance of environmental effects in order to not only thrive, but to survive.
Without these conditions met, the body will break down internally and life will cease. The Earth’s atmosphere is where we experience our first problem in regards to humans in space and potentially on other planets, both within and outside our solar system. The Earth’s atmosphere is made up of 78% nitrogen, 21% oxygen, 0. 5% water vapor, along with small amounts of other various trace gases. Though the levels of these gases will vary depending on variables such as temperature, altitude and humidity, humans have evolved over the millennia to rely on this particular mixture (Lujan & White, http://www. sbri. org/HumanPhysSpace/index. html). Every breath you take draws this mixture of “air” into our lungs, saturating our blood with oxygen which is then carried to the different parts of our bodies and fueling our existence. As we exhale, carbon dioxide is expelled, completing the act of breathing. This mixture of gases is essential to human survival (Lujan & White, http://www. nsbri. org/HumanPhysSpace/index. html). In addition to the correct mixture of gases in our atmosphere, the pressure of our atmosphere is also vital to human survival.
Atmospheric pressure measures the force exerted by gas molecules in the air with any surface in which they come in contact (Lujan & White, http://www. nsbri. org/HumanPhysSpace/index. html). This atmospheric pressure pushes the air into your lungs while the lungs exert pressure pushing the waste carbon dioxide back into the atmosphere. This pressure is necessary to humans breathing, as the correct pressure allows us to breathe without effort when not exerting our bodies. Heavy or thin atmospheric pressure makes it difficult to breath, and if it becomes too much of one, the human body will not be able to function properly.
This is why density of molecules is also important to human survival. Density refers to the number of molecules in relation to a given volume, while kinetic energy (speed at which molecules move) greatly influence pressure. A larger density of molecules means heavier pressure, something the human body is not accustomed to. However, a greater number of molecules also means that there are more collisions, which produces greater speeds resulting in more collisions. The faster the molecules move and interact, the greater the temperature that is produced.
Pressure relating to breathing is a major concern when considering space exploration and colonization. A concern also worth mention when dealing with pressure and density is the heat, or lack of, generated from the collisions that occur. The human body runs optimally at a temperature of approximately 98. 6 degrees Fahrenheit. Any temperature too high above or far below this could result in the death of the human body. Most humans realize that air and atmosphere are essential for human’s survival, regardless of whether they know the exact reason why.
The reason this is problematic when dealing with space travel and exploration comes from space itself. Space is considered a vacuum, which means any molecules that may be present are available in such small numbers that it is considered to have no atmosphere. We can create vacuums on earth in chambers designed to reduce atmosphere and pressure, but no laboratory on earth can create a vacuum as complete as that found in space (Lujan & White, http://www. nsbri. org/HumanPhysSpace/index. html). Creating these vacuums on earth allow us to test theory and methods for combating the effects, particularly when testing new equipment or technology.
However, to get a true gauge of whether technology and equipment is truly effective, space tests are still the best option. This means potentially putting humans in harm’s way in order to achieve accurate results. With these questions in mind, what are the options available to make space travel and exploration possible? Suits and vessels capable of sustaining the correct atmosphere and pressure have been in use for better than 70 years capable of allowing living beings to cope with the stresses involved with space.
However, these technologies are not yet nearly advanced enough to consider prolonged exploration in terms of years or even decades. In order to allow humans to reach the deeper spaces, greater knowledge and technology will be necessary to allow for adaptation while en route to a destination. Oxygen and other essential gasses must be carried into space for use in breathing, not to mention renewable power sources, food sources and raw resources to allow for upgrading and repairing crafts. The technology present, though more advanced than ever seen by humans, needs to be better if that’s what will be relied upon.
Another option, though in its infancy in terms of testing and usability, would be that of genetic modification. The ability to alter human physiology could be essential to coping with stresses involved in space travel and planetary colonization. Allowing humans to thrive in various atmospheres, pressure ranges and heat or cold tolerance would allow us to not only possibly use current technology more effectively, but eventually possibly not need it at all. As it stands, the suits used to perform space walks and walking on the moon are heavy, cumbersome and not terribly efficient for precise and prolonged work.
Genetic modification may allow us to create thinner suits which are not only more maneuverable, but better equipped to effectively work and explore. It may allow humans to carry less air if they are modified to survive and function with different combinations or amounts. There are creatures on this earth which function in both very thin atmospheres, as well as deep sea creatures surviving with little to no oxygen in extreme heat and heavy pressure. It’s not unreasonable to think that these traits could eventually be used to alter human anatomy in such a way to make them more tolerant to extremes that would kill a normal person.
Of course, this raises ethical and moral questions about whether or not these humans would be considered human after such changes. In addition to these questions, a human endowed with these traits may never be able to set foot on Earth again without the aid of suits allowing them to survive in this environment. In addition to providing life sustaining properties, the Earth’s atmosphere also serves another vital purpose, and that is to filter out the Sun’s ultraviolet (non-ionizing) and the more harmful ionizing radiation present in space. Radiation is simply energy that spreads along its path.
There are many forms of non-harmful radiation present which we use in everyday life. These may include things like visible light from a lamp for instance, or radio waves which are picked up by your stereo, and are called electromagnetic (EM) radiation. “Other EM radiations include microwaves, infrared and ultraviolet light, X-rays and gamma rays (Lujan & White, http://www. nsbri. org/HumanPhysSpace/index. html). Ionizing radiation can refer to EM radiation, or energetic nuclear particles capable of producing charged atoms known as ions as they pass through matter, and is known as ionization.
Ionization happens when the atoms in a cell are bombarded by radiation and an electron is either added or taken away, resulting in the atom being given a charge (Lujan & White, http://www. nsbri. org/HumanPhysSpace/index. html). This can cause a host of problems in the human body, such as chromosomes being destroyed or mutating cells which have been linked to certain cancers. This kind of radiation is plentiful in space, and upon arriving at the Earth’s atmosphere, the majority is filtered out before reaching the surface.
Galactic cosmic radiation and solar particle radiation are the two types of radiation found in space, and both are dangerous to humans. Galactic cosmic radiation comes from outside our solar system, while solar particle radiation originates from the sun and the solar flares produced. It is thought that relatively short-term space exploration, even to a planet as close as Mars would not be possible due to the massive amounts of harmful radiation. With current technology, prolonged exposure to the radiation present in space poses a lethal problem to astronauts.
However, there are a few alternatives to present technology in development that may allow us to reach not only within our solar system, but beyond it as well. Current technology relies on shielding composed of aluminum shells to shield astronauts from the effects of space radiation. Though this is effective for a relatively short amount of time, it is not viable in terms of multi-year missions. One such technology being studied relies on electrostatic charges to defeat harmful particles before they reach inside a manned spacecraft.
The team behind the development of this technology is considering setting up multiple spheres surrounding the spacecraft. The center sphere, attached to the crew quarters, would hold a positive charge. The two outer spheres would carry a negative charge. This combination, in theory, should be enough to repel high-energy protons and electrons which would normally penetrate the spacecraft. It is also necessary to develop better suits if we wish to battle the effects of space radiation. The suits used to walk in space or the moon are effective for a short time.
If we were to visit or colonize a planet such as Mars, the lack of atmosphere or magnetic fields would mean the radiation would be present in much higher amounts than previously seen. In order to assure our future as a species that is able to explore and colonize planets in our solar system and beyond, the technology to protect our astronauts needs to improve immensely. Another problem which needs to be overcome if humans are to spend large amounts of time in space is solving the gravity dilemma. Humans, as well as every other structure and being, are held to the Earth by the force of gravity.
Gravity is a result of the attraction between two masses toward each other. Due to the Earth’s large mass, and our relatively small mass coupled with our close proximity, we are drawn to the surface. The farther a person or object moves from the surface of the Earth, the pull of gravity lessens. Spacecraft orbiting the earth are still under the effects of Earth’s gravitational pull; though a spacecraft moving at high velocity with very little atmospheric friction can overcome the downward pull of gravity. To better understand how gravity affects an object, consider throwing a ball at ground level.
Assuming it could be thrown fast enough, the speed moving forward could be greater than the pull of gravity allowing the ball to seemingly orbit the Earth at a very low level. Producing enough velocity would not be the only condition to consider while in the Earth’s atmosphere, but the friction of particles in the atmosphere also hinders that possibility. Space is a near vacuum, allowing an object in motion at speed to maintain that speed without the need for thrust. This creates what is commonly called zero gravity, though it is not true zero g. The amount of ravity while astronauts are in orbit in so small that only the most precise instruments can measure the gravity present. The human body has evolved in an environment consisting of a constant gravitational pull. Everything from our bone structure, muscle mass, circulatory system and organs operate ideally with the constant pull of Earth’s gravitational pull. There are many problems within the body that arise from prolonged exposure to near zero gravity. Bone density loss, muscle atrophy and strength loss, as well as effects such as fluid shift when dealing with the cardiovascular system (http://library. thinkquest. rg/03oct/02144/text/travel/body. htm). Our skeletal structure is designed to resist the gravitational pull, allowing us to remain upright in a high gravity environment. Without our bones to support us on Earth, activities such as standing, walking and simply moving at all would not be possible. The muscles we use give us the strength to move our body when in the pull of Earth’s gravity. Such simple things as walking, lifting your arms or anything requiring the use of muscle is done while resisting the pull of gravity. Our cardiovascular system operates by pumping bodily fluids to the vital areas of the body.
Gravity tends to make the fluids settle near the bottom of the human body. “Various gravity opposing mechanisms force the blood and fluids back up to vital organs on a daily basis. The circulation of these fluids still happens in zero gravity, though the negative effects can include such things as headaches, stuffy nose or puffy faces” (Lujan & White, http://www. nsbri. org/HumanPhysSpace/index. html). When dealing with bone density loss, it is of vital importance to remember that the effects of zero gravity begin immediately upon entering space. The removal of gravitational stresses means that the human body averages a 3. % bone loss after only 10 days (Lujan & White, http://www. nsbri. org/HumanPhysSpace/index. html). The Calcium and phosphorous are excreted in urine and human waste at a rapid rate. The loss of bone density can lead to a severe weakening of the skeletal structure, making it not only difficult for the body to support itself when it reenters the gravitational pull of earth, but a greater likelihood for fractures and breaks. There are drugs being used today that could help in dealing with bone density loss. Many people are treated on a daily basis for osteoporosis, a condition which leads to the weakening of bones.
Bisphosphonates are medications used to slow the breakdown of bones. These drugs have been shown to slow the rate at which bone breakdown occurs, and are used particularly in elderly patients suffering from osteoporosis. However, these drugs have shown promise in helping astronauts deal with the issue of bone loss while in space. It has still not been determined if the effects of these drugs would be effective over a journey of many years, but it is a start in the right direction in regards to space exploration. Another option lies in genetic engineering and altering the human body to better handle the stresses space travel places on bones.
In humans, the breakdown of bones, whether from osteoporosis or other conditions, is a fault of the aging human body. If humans could be engineered to have a consistent bone density which would not break down, regardless of the environment they are in, this could solve the problem at hand. A journey of years with no bone density loss would allow us to reach and explore distant worlds without the problem of being potentially unfit to explore once we arrived. The other main drawback of zero gravity is the amount of muscle loss which occurs. While on Earth, every movement is done with gravity as a major resistance component.
Taking away gravity means that any movement done requires such a small effort that the muscle is not worked adequately. This leads to major muscle loss and atrophy. In space, an object which may take many people to move can easily be moved by the slightest touch of one person. This lack of movement and the problems it causes may not be readily apparent while in space, but becomes very noticeable as gravity is reapplied to the body. The goal would be to maintain muscle mass while in zero gravity, allowing us the ability to maneuver and operate effectively after long space flights.
This can be done today, though the effects are not nearly enough to keep the muscle at full effectiveness. Exercise done by using machines with resistance bands or cords would help keep the muscle in tone. However, considering the amount of strength our muscles gain on Earth by doing anything requiring movement, exercise may not be a feasible long term solution due to the amount that would need to be done. Another technology being discussed as a potential solution is the use of nanotechnology. The ability for nanotechnology to produce or repair damaged tissue using healthy tissue could be a viable application.
Tissue engineering uses artificially stimulated cell development to produce new tissues based on healthy cells. Advances in tissue engineering could not only be used in muscle maintenance, but may lead to the repair of damaged organs. Advancing this technology could not only lead to a healthier human, but may also lead to life extension, which would also be important when discussing long term goals of space exploration. The last technology when dealing with pitfalls of zero gravity would be to produce a means of creating artificial gravity.
Producing artificial gravity is a relatively simple procedure, and can be done today. Centrifuges are used all the time to produce the effects of gravity. As they spin at high rates, the contents within are pressed outward away from the rotational axis. This force simulates the feel and effects of gravity. The ability to rotate an entire spacecraft could be more difficult, both with cost and engineering. The stresses place upon the structure of a ship could potentially tear it apart if it were not strong enough (http://science. nasa. gov/science-news/science-at-nasa/2002/30sept_spacemedicine/).
The use of an ultra dense object may produce a gravitational field, not artificial but natural, that could be used to for space travel. Considering that natural gravity is based upon mass of an object, this material would need to be small enough to feasibly fit within a craft while being dense enough to produce a suitable gravitational pull. Scientists believe that there are materials present in the universe that could fit this mold. One question that arises from using a material dense enough to produce gravity would be our ability to sufficiently propel it during space travel with our current propulsion technology.
The physical effects on human kind during space travel are varied and extremely important to overcome. In addition to the problems we now face, the implications of problems unknown to us are just as daunting. We realize that the human body, as it has evolved on Earth, is not designed to survive at length in space. Many more issues are coming to light that will need to be addressed as well. How will humanity manage the body as it ages during long space flights? Life extension through genetic modifications will help humans during exploration reach further into the universe.
The effects of children born in space is also an unknown factor. Will being born in zero gravity have major effects on muscle, bone or brain development? The science of space exploration has solved a plethora of potential problems faced by humanity, while its ongoing research continues to bring new and potentially hazardous problems to light. The psychological effects of living in space, both short-term and long-term, are well documented. Spending months, or potentially years, in an area not much larger than a small house with other astronauts is taxing in itself.
Adding the stresses of zero gravity, mission objectives and distance from home to the equation, the psychological welfare of astronauts is an area that will need to be addressed. Anxiety, depression and sleep deprivation are all common problems experienced by astronauts while in space. This can lead to loss of motivation and be extremely counter-productive to what humanity is hoping to achieve in terms of deep space exploration and colonization (Kanas 2008). One possible solution to this is to provide adequate areas for astronauts to have privacy from one another.
Privacy at this point of space travel is considered a luxury and not a necessity. Though social creatures, I believe this will need to be changed for the success of exploration to be realized. Due to cost and engineering, it may not be plausible to simply make larger spacecraft. A possibility to combat this problem would be virtual reality or virtual worlds. The idea that an astronaut could “plug” themselves into a virtual world, allowing for leisurely activities not possible on the spacecraft may help combat many of these problems.
There are many virtual worlds available for computer users today, and the ability to experience new activities and places within this world are staggering. Though most of these virtual worlds are done while using a computer and screen, the next step in the evolution of this technology is to make them truly virtual. We see these worlds visually on our screen at present, but have the ability to interact with both the environment and people within it as if we are in that world.
The ability to see this world not from a screen, but rather within our own minds may help give the sense of privacy needed to maintain psychological health. It is not something that is reality at this point, but the future of computers and technology are wide open and developing at a rapid pace. Virtual reality may well be the key to helping maintain mental health for our future explorers delving into the depths of space. The technology of propulsion systems may not seem to deal directly with human enhancements, but it is definitely associated indirectly with it.
The current limitations of the human life must allow us to consider finding faster and more efficient ways to travel around not only our own solar system, but possibly the universe. Gene alteration and human enhancements may find a way to lengthen the human life, but finding faster methods of traversing space will be necessary regardless of our lifespan. Spacecraft today use rocket engines which are essentially combustion by using a solid, liquid or gaseous fuel with an oxidizer in an internal combustion chamber. The hot gas produced escapes through a nozzle designed to focus the energy and produce thrust.
The nozzle accelerates the mass and converts the thermal energy to kinetic energy. This form of propulsion is very effective for breaking the Earth’s gravitational pull, however it is not terribly cost effective and the amount of fuel needed to sustain a long-term space exploration would be very difficult to store. Though rocket engines are successful for use in launching spacecraft into orbit, the feasibility of using these methods over distance would not be sufficient. The best option is to find a method which uses much less fuel, or relies on a renewable source for travel.
Ion thrusters are a propulsion system in development that holds future promise, though the amount of thrust produced pales in comparison to present rocket engine technology. Ion engines accelerate electrically charged atoms, or ions, through an electric field. This push of ions pushes the spacecraft in the opposite direction, therefore producing thrust. Ion engines provide less thrust than conventional chemical rocket engines, which means ion engines are not capable of breaking the pull of Earth’s gravity and obtaining orbit on their own. The difference between ion engines and chemical engines can be seen once in space.
Where a rocket uses most of its fuel to break through the atmosphere of Earth, ion engines are capable of producing a steady thrust for years. This thrust gradually accelerates the spacecraft until they are moving faster than conventional rockets. The only drawback is the amount of power necessary to run these engines is massive. The electric power source needed to both ionize atoms and produce the voltage needed to accelerate those ions to high exhaust velocities is both massive in size and impossible to keep powered, at least on craft capable of carrying humans across the vast expanses of space.
New technology is being developed on ion engines which will both increase thrust as well as decreasing energy needed to operate. Another source of propulsion being contemplated by scientists is that of propulsion without the use of internal combustion or reaction. Space may be devoid of atmosphere as we know it, though it is not empty. Gravitational fields, magnetic fields and solar wind and radiation are all abundant within our solar system. In order to capture these energies, large sail like structures are being developed to harness these phenomena.
The only drawback is the size of the sail needed, which needs to be proportionately large as these fields are relatively diffuse (http://www. humansfuture. org/space_colonization_propulsive_systems. php. htm). This form of travel would require little to no combustion to function efficiently, though coupling sail technology with conventional propulsion could make it much more effective. A method of travel which is supported by many scientists is the Generation Ship method. The name is self explanatory in how this concept works.
For this idea to gain acceptance, it would be necessary to produce a spacecraft large enough to carry hundreds of people through deep space, hold enough fuel for the journey and be capable of producing a self sustaining environment. For Generation Ships, speed is not the necessary component for propulsion to achieve success, so concepts such as ion or solar sails could be plausible (Harland 2008). Of greater importance would be to assure that the subsequent generations of children born on the craft are healthy and capable of continuing the journey.
This could best be achieved by gene manipulation or modification. Insuring that the generations born aboard the ship are physically and mentally superior, as well as ensuring each function of the ship could be covered in every generation. Producing offspring in this instance strong in sciences, math and physics would be extremely beneficial. Assuming that future science will hold the key to enhance the human brain well beyond current capabilities, Generation Ships are a very real possibility to spread humanity throughout the galaxy and colonize distant worlds.
For the majority of our purposes, humans still use methods which were in essence developed thousands of years ago. China had developed fireworks, which in effect use solid fuel in a combustion chamber to produce thrust out of a single nozzle like end. The technology and fuels used today are much more advanced, though the principle is essentially the same. When looking at propulsion methods, it may be better to consider pairing technologies rather than relying on developing single modes of transport. By themselves, each form has positives and negatives which need to be considered.
However, coupling combustion with ion, for example, would produce the ability to reach high velocity quickly while sustaining those speeds would require relatively small amounts of fuel provided by ion technology. In conclusion, it is easy to recognize the problems humanity faces with prolonged space exploration. There are a great number of physical, psychological and time related hurdles which will need to be addressed in order to make this a reality. The human body has evolved to survive within a very strict set of conditions. The Earth’s atmosphere and gravitational pull have shaped and molded our bodies over thousands of years.
The first attempts at space travel have relied solely on technology to overcome the barriers of survival in space conditions. Spacecraft shielding, suits and atmosphere producing technology allow us to survive over short periods of time. If humanity is to delve into the outer reaches of our solar system, more must be done. Genetic enhancements and modifications are the most likely way to accomplish this. Finding ways to alter a person internally, in a way to evolve them through science, will be necessary to achieve true exploration.
Stronger bones, more resilient muscle mass, organisms capable of repairing and building tissues; these are all things in development, whether through alteration or medical research, which are on the horizon. As technology continues to evolve and develop, new ideas will continue to develop. The space program, though having achieved great achievements to this point, is still in essence in its infancy. Technology has developed at such a rapid rate that the possibilities are endless. For thousands of years, man has dreamed of reaching the stars.
The past one hundred years, man finally touched the edge of space. The future, man will not only reach into space, but spread our history to the heavens. We have only just begun to realize what is on the horizon, and with the ingenuity and drive humanity has shown, the possibilities are endless.