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The Martian Federation Society
Copyright 2017 by Raul E, Lopez, MD
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Why Colonize Phobos and Deimos.
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INTRODUCTION
As we set out to colonize the solar system, a venture with a very high initial cost, we need to wisely determine where exactly to begin this venture. How do we best get from the present to our space future. What has been tried up to this point has not produced anything near a viable, self sustaining settlement. The purpose of this website and this organization is to propose the moons of Mars as the simplest bodies in which to establish a viable, self sustaining settlement in space.
ABSTRACT
The moons of Mars are among the most accesible objects in the Solar System but they have recieved very little attention. We will make the case that they are actually the ideal place for establishing the first permanently manned base in space. The first step should be a sample return mission in the form of two landers, one to each of the Martian moons. The mission could be privately funded and money recovered by selling samples to universities and research labs through out the world. We discuss the design of such a mission and also discuss simpler alternatives.
ADVANTAGES TO MARS
Mars is probably the ultimate goal for space settlement. It is likely that millions of people will live on Mars in the next century. However, that does not mean that it serves as a good first goal. If we start with the final goal we might stumble and never reach it.
Mars is the most Earth-like planet in our solar system and has all the resources necessary to support a large human population. This includes water, carbon dioxide, and all necessary metal ores. It also has a 24 hour day and an orbital inclination similar to that of Earth. Its surface area is nearly the same as that of the land mass of the Earth so, in theory, it could support a population similar to that of Earth.
OBSTACLES TO MARS
Costly Return Trip
The main obstacle to the colonization of Mars is the cost of the return trip from Mars back to Earth. Mars lies at the bottom of a significant gravity well and getting back takes a lot of energy. The most feasible plan to colonize Mars is the concept promoted by Mars One, which promotes a one way ticket to Mars. However, as the plan now stands, those who go would be committing themselves to spending the rest of their life on a strange world surrounded by very few people and would have to forego ever having children and a family. Even if a surgeon was a member of the team, he would not be able to maintain the skills needed for complex surgery as the population ages and needs more medical care. Not only are very few people willing to make such a sacrifice, this does not really produce a viable settlement.
Low Gravity
Furthermore, even thought the gravity on Mars is high enough to be a very important obstacle for a return trip, it is probably too low to permit human health. We do not know what the long term effects of Mars gravity would be on human physiology. However, it is likely that it would lead to loss of bone mass which would, at the very least, make it difficult for people to adapt to Earth gravity after spending a significant amount of time on Mars. It is possible that children who are raised on Mars would grow taller and larger and over several generations humans would adapt genetically to the low gravity environment producing what would become a new race of humanity. However, in the short term it is likely that humans would have to live in rotating colonies which produce near Earth gravity. However, the gravity which does exist on Mars would make such structures quite heavy and difficult to construct.
Distance
Mars is too far away for exploration and development to be done by robotic telepresence. The time it takes to send a signal and get a response varies depending on the position of Earth and Mars in their orbits but it varies from 6 minutes to 44 minutes. We are still many decades away from robots which are intelligent enough to explore Mars effectively with little human supervision. The robotic rovers have brought back a lot of information but they cannot accomplish complex tasks such as digging or assembling complex structures.
ADVANTAGES FOR LOW EARTH ORBIT
The greatest advantage to settlement in Low Earth Orbit (LEO) is accessibility. This is obviously the most accessible part of space and people have already spent months at a time in space stations located there.
Furthermore, the magnetic field of the Earth shields occupants from cosmic rays, making heavy shielding unnecessary.
DISADVANTAGES FOR LOW EARTH ORBIT
The greatest disadvantage to LEO is a complete lack of physical resources. The only resources available are non physical, solar energy and weightlessness. At the moment, everything else must be brought from Earth at very high costs. However, one needs physical objects to gather solar energy, and a manned space station is a poor place to conduct low gravity experiments because of the vibrations caused by the motion of humans. It is more efficient to conduct such experiments on an unmanned platform where the experiments can be accessed by robotic teleoperators.
Furthermore, Low Earth Orbit is somewhat congested with multiple satellites and, more significantly, satellite debris. This includes small particles from explosions and satellites collisions. Small and medium size structures, such as satellites and the International Space Station can maneuver out of the way of such debris, but large spinning space stations with artificial gravity would require heavy shielding. Bringing such shielding from Earth is prohibitly expensive.
ADVANTAGES OF THE MOON
The moon is the nearest source of physical resources in space. It is accessible enough that twelve people walked on the moon using 1950's and 60's technology. It takes about three days to get there and three days to return. This means that the moon will continue to be a likely early target for habitation.
DISADVANTAGES OF THE MOON
The moon presents some significant obstacles to settlement. Some are short term and some long term. One problem is the lack of significant reserves of volatiles. There seems to be small quantities of water ice in the polar regions. There appears to be an estimated 600 million tons of water stored in those deposits. That seems like a lot of water, but it is the equivalent of a lake 10 meters deep (30 feet) and 7 kilometers by 7 kilometers in area (about 4.5 by 4.5 miles). This is a great resource but not enough to build a significant civilization on the moon. Furthermore, it is scattered across a large number of cold shaded craters so there will probably be significant extraction costs. One can extract oxygen from water, but nitrogen is scarce.
Gravity presents problems similar to Mars. The gravity is too low to allow healthy habitation for extended periods of time without spinning habitats to provide near normal gravity. Even though the gravity well of the moon is less than that of Mars, which makes the return trip less difficult, the moon lacks an atmosphere which could be used to slow down approaching space craft. This means that rocket propulsion needs to be used to slow down a landing spacecraft, a process which consumes precious fuel, in addition to the fuel needed to take off.
The length of the day on the moon is about one month, since the moon is tidally locked to the Earth, so that its day and its orbital time are the same. This makes using solar energy difficult both for growing plants and for producing electricity. Crop plants will die after several days without sunlight. In order to use solar energy for electricity there must be ways to store two weeks worth of electricity. This means the use of very large battery banks or fuel cells. Imagine the amount of batteries that would be necessary to run a house on Earth for two week, including air conditioning or heating.
ADVANTAGES FOR THE MOONS OF MARS
Phobos and Diemos are among the most accessible bodies in the solar system. The return trip is cheaper than even from the moon. Because of the low gravity, the round trip takes less energy than going to the moon and returning. This means that people could go live there for some time and return to Earth when they wish. Even though micro gravity is a problem for human physiology, it makes the construction of spinning habitats easier because their low weight means that support structures could be light. It would also be easy to bury the spinning habitats under regolith, which would provide shielding. The micro gravity also means that the lunar material could be mined all the way through to the center which makes large quantities of material available for processing. The deepest mines on Earth are only about 4 km under the surface. Phobos has a mean radius of 11 km and could easily be mined all the way through.
The moons appear to be similar in composition to a D-type asteroid with a composition similar to those of carbonaceous chondrite meteorites. These contain carbon and other organic compounds, including nitrogen bearing amino-acids. These compounds are essential for sustaining life, and are not found on the moon. Furthermore, the moons have a very low density which means that they are either very porous (more than 30% empty space) or else contain large amounts of water ice in their interiors (or a combination of both). If the full 30% empty space was water ice, that would be equivalent of 1.7 trillion tons of water just on phobos, almost 3000 times what is supposed to exist on Luna (our moon). That is more than a third of the amount of water contained in lake Michigan, enough to run a civilization for a couple of centuries.
Since Phobos and Deimos are close to Mars, they would be an ideal site to perform telepresence robotic operations. One could send robots to the Martian surface to explore and set up settlements operated by people on the moons of Mars. This is a task which the first colonists on Mars would have to do anyways, and it would probably be cheaper to leave the human operators in Mars orbit where they could be easily supplied and could return cheaply to Earth.
DISADVANTAGES FOR THE MOONS OF MARS
If there were moons like Phobos and Deimos in Earth orbit we probably would have already set up a base there. However, one disadvantage compared with the Moon is the distance. However, this is the same as going to Mars and the same solutions would work. After the first few trips transorbital transfer shuttles would probably be built with moderate shielding which would continuosly make the trip between Earth and Mars. Habitats on the moons of Mars would have to be enclosed and underground. However, because of the low gravity, it would be almost no different than orbital habitats, and the shielding is already in place.
Some might think that small moons like the moons of Mars are a poor location for establishing the first outpost of a space faring civilization. Compared to the resources of Mars, these seem like small fish. However, it is hard for us to grasp the concept of developing a settlement in three dimensions. Because of the microgravity on these bodies, in theory, habitats could be located throughout the whole volume of the moon. The volume of Phobos is 5783 cubic kilometers which really an enormous amount of space. If one assigned a cubic acre (63mx63mx63m) to every inhabitant, one could fit a population of 22 million people inside this moon. If one, instead used the amount of volume taken up by people living on habitats such as the proposed kolpana one cilinder, one could fit a population 40 times as large, 880 million people, close to the population of the largest countries on Earth, more than twice the population of the United States. Concrete buildings are about 75% hollow which means that a given volume of raw material could possibly produce more than four times the amount of volume, so there is plenty of room to house a huge population.
If one uses the amount of sunlight landing on the moons as the factor limiting the size of the population, one could still achieve a population of more than a million if one covered the surface of the moon with solar cells. The energy use of a person in the United States, based on the equivalent of oil consumption per capita is about 10Kw per person. The use of electricity instead of oil and the fact that people would live in large enclosed structures would probably significantly reduce this figure. On Earth much of this energy is used for transportation and heating/air conditioning. The efficiency of solar cells varies, but 20% conversion efficiency is reasonable. Since the average radius of Phobos is 11km and insolation at Mars orbit is 590 W/m2 so one could produce 44 million kilowatts of electricity if Phobos was covered with solar cells.
However, the greatest human use of energy is solar energy used by plants in food production. It takes about an acre to feed one person in New York who consumes the typical North American diet. However, land is farmed about 90 summer days out of the year when insolation is 4kwh per day per m2 to give about 1.5 million kwh per person per year. Evened out this would be 166 kW per person. However, efficiency could probably be doubled or tripled in enclosed conditions and there are more energy efficient diets than the typical North American diet. Therefore, it is reasonable that one could feed people using about 40kW per person. If one ads the 10kW mentioned above, the total consumption would be 50kW per person and that would mean a population of about one million on Phobos. Even a tenth this number would be a great start to space colonization and, of course, fusion energy would completely change the picture.
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