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8/12/2019 Selene Expandable Space Settlement
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Table of Contents
I. Introduction
1.1 Foreword
1.2 Reasons to Build a Space Settlement
1.3 The Name Selene
II. Financing
2.1 How Important Financing Is
2.2 Source of Possible Financing
2.3 Development Plan
III. Position in Space
3.1 Best Position in Space
3.2 Choosing the Position
3.3 Advantages and Disadvantages
IV. Mining the Space
4.1 Mining the Moon
4.2 Mining the NEO
V. Space Travel and Construction
5.1 Propulsion Systems
5.2 Expansibility Principle
5.3 Structure and Aspect of the Space Settlement
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5.4 Artificial Gravity
5.5 Shielding
VI. Human Needs and Factors
6.1 Food
6.2 Water
6.3 Atmosphere, Weather and Climate
6.4 Lighting and Day/ Night Cycle
VII. Resource Management
7.1 Solar Power and Nuclear Power
7.2 Recycling
7.3 Energy
VIII. Social System
8.1 Government
8.2 Education
8.3 Religion
8.4 Population Selection
IX. Urban Infrastructure
9.1 Leisure Places
9.2 Medical System
9.3 Restaurants and Hotels
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I. Introduction
It is difficult to say what is impossible, for the dream of yesterday is the hope of today
and reality of tomorrow.
Robert Goddard
1.1 Foreword
As we all know, considering how often we hear about solar flares, global
warming, pollution and various other disasters which all impede the expansion of the
human race (and bearing in mind that the Earths population is constantly growing) it is
essential to find a new alternative, a new way to extend our reaches and of course build
a new future for our descendants.
Taking into account the remarkable moments that have changed the history of
space travel, such as the first rocket launched into space or the very first moon landing,
we are even more determined to try to make a start, a start toward something new,
something that the entire human race could benefit from.
Exactly for these reasons and also due to our huge passion for research in
space, we are very determined to tackle the ample domain of space colonization. This
colonization of the space would be put into perspective by building, step by step, a
Space Settlement.
Just as physicists and writers of the 19th, 20th and 21st centuries, such as
Konstantin Tsiolkowsky (Beyond the Planet Earth1900) or Gerard K. O'Neill (The
High Frontier: Human Colonies in Space- 1977) and others have exhibited dreams and
ideas about space colonization, we, the people who share the same dreams, would like
to continue with our project, as part of the plans and ideas of these pioneers of space
colonization.
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We would like to take this opportunity to thank all the persons who have
contributed in the different aspects of this project. They have all made it possible for us
to commence, develop and complete this complex task. We would like to acknowledgeand commend them for their effort, cooperation, ideas and collaboration that have
worked towards the success of this project.
First of all, the work would not have been possible without the contribution and
involvement of our coordinating teacher Ioana Stoica who has deeply inspired and
motivated us in order to participate at this project.
Also, we thank the National High School of Computer Science Tudor Vianu,because this high school has taught us day by day (and continues to do so) precious life
lessons and values. We strongly affirm that we could not be any happier to be a part
of it.
We are deeply grateful to NASA and NSS for organizing this contest, which made
us not only enlarge our knowledge as far as space and technology is concerned, but
also our team-work, cooperation and creativity.
We would like to acknowledge the contribution of our classmates, who
unceasingly motivated us in trying to exceed our limits in order to do a better project and
our family and friends, who always gave us the needed support.
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1.2 Reasons to Build a Space Settlement
The future cannot be predicted, but futures can be invented.
Dennis Gabor, 1963
As previously stated, the idea of space colonization is a research topic that has
preoccupied people since the ancient times. Nowadays, building a space settlement is
something necessary, useful and at the same time unique and innovative.
Relevant to this case would also be the rebuttal of a famous physicist, professor
at a world-renowned university, who said: I don`t believe that humanity will survive the
next 1,000 years unless it will move to another planet- Stephen Hawking. Given his
statement, which brings forward the idea that the Earth is constantly at threat from
major pressing issues such as global warming, nuclear conflict, genetically modified
viruses or other possible disasters, we have decided to get involved and support the
idea of space colonization by building a space settlement. In our project well try to
make this construction possible, and simultaneously ensuring that the welfare of oursettlers is up to standard.
1.3 The Name Selene
Considering the fact that most of the materials needed for building the space
settlement, such as regolith, silicon, oxygen, hydrogen and even water, will be extracted
from the Moon, we decided to name our project Selene. In the Greek mythologySelenes parents are the titan Hyperion, the sun-god, and Theia, sister of Helios.
Selene is known to be the titan goddess of the Moon. She is portrayed like a
young woman with a very pale face, traveling in a silver chariot drawn by two horses.
She is often depicted riding a horse or a bull.
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Even though a number of other Gods were also associated with the Moon, the
only one who was represented by the ancient Greeks as the Moon incarnation was
Selene.
So, in order to introduce you in the space atmosphere, we decided to name our
space settlement Selene.
Selene, the titan goddess of the MoonSource:http://en.wikipedia.org/wiki/File:Luna_statue.jpg
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II. Financing
All things are possible until they are proved impossible and even the impossible may
only be so, as of now.
Pearl S. Buck
2.1 How Important Financing Is
Money is clearly one of the essential means for sustaining a project, because
funds can provide a full arsenal of resources for its development. Thus, without the
benefit of financial support (to ensure the gathering of the necessary resources), thedevelopment of a space project might not be possible. These possible resources may
include labor or material resources. We decided to include the economic factors in the
development of our project because the development represents an essential part of all
the required resources. Taking into consideration that our project will be quite
substantial, we will need a fairly large amount of financial resources that we will use to
pay for the labor and materials required.
2.2 Source of Possible Financing
While searching for the best sources of funding for our project we found that
possible funding sources could be: the government, the business community and
society as a whole. Considering the fact that the first funds obtained for space projects
were provided by the government, we also decided to use this source in order to fund
our project successfully. At the same time, internal governmental representatives and
other external sources of money procurement are those who contribute to the
development of space projects.
We have to put all this into perspective and relate it to the actual situation on
Earth. The population is growing, but at the same time the economical and physical
resources are slowly being depleted. But it is unlikely that the governments will fund
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such a big project by investing billions of dollars in it, instead of investing in
infrastructure or improving other sectors of their economies. Also, it is to be noted that
this is definitely a more ambitious and complex project than Apollo 11 or ISS.
However, we think that this is the future and even if the future costs a lot of
money, this project is capable of giving in return even larger amounts of assets than the
consumed ones.
We tried to develop a business strategy which would offer the best arguments so
that the above mentioned would invest the optimum amount of money into our project.In the beginning, we have not made any calculations regarding the money which should
be invested. We tried to get an idea regarding what total this project would come to by
looking into a particular case: Apollo 11 in 1969 cost $335 million (equal $1.75 billion
nowadays) and transported only two people in space. We have to transport more than
just two people into space and obviously the costs will rise, but we benefit a lot from
todays technology such as the U.S. Space Launch System (SLS) which was designed
to provide the capability of human exploration in the 21stcentury. The SLS can be easily
used for cargo missions because the SLS will be safe, affordable, and sustainable, to
continue America's journey of discovery from the unique vantage point of space.1
First of all, we have to evaluate what human hazards involve. These hazards
consist of objects placed in orbit which encounter pieces of orbital debris (which are
parts of satellites which failed their missions). Hazardous elements like nuclear waste
and biological samples can also be encountered.
Next, we should address the problem of asteroid hazards. Dangers manifested
by asteroids may consist in their deviation due to different spatial phenomena. This
1http://www.nasa.gov/exploration/systems/sls/index.html
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deviation can lead to devastating damage, as an object that weighs about a ton would
cause enormous casualties.
The last hazard that we are going to present is the comet hazard. The danger
represented by comet hazards consists in the fact that they are almost impossible to
detect, considering that their consistence makes them natural rocket thrusters.
One of the easier methods (because the main operation does not require any
kind of process) which may be able to help us is bringing big amounts of Iron to Earth.
The modus operandi would be aiming pieces that float into space, fragments of metallicasteroids, to a previously selected spot and simply gathering the objects which fall on
the ground.
Space Debris around Earth
We included this fragment into our project because we find it important in order to
make a short presentation about some dangerous and unforeseeable facts which may
occur. As known, since the process of sending missions in space started, nobody hastaken care of the remains of satellites or of the thousands of small parts which can
represent a danger for all kind of space missions.
Space debris can also be regarded as a considerable source of materials (for
example, we can design a kind of vehicle which will be able to collect debris).
Another advantage, despite being a source of materials, is represented by its
capacity of clearing the space around Earth, making it safer for the following space
missions.
Various energy demands should be taken into account for designing a space
settlement. In order of the demanded power, the energy consumers are: industry,
population, transportation systems, other activities and agriculture.
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Taking into account that the worlds resources of natural oil and gases are
running out and, as we previously mentioned, there is a big number of people, it results
that the demand for energy is increasing every day. The renewable energy has a smallshare from the world power generation. The sun is able to offer energy for a short
period of time, the wind does not blow every day and geothermal energy cannot be
found in every region of Earth. Considering what we mentioned earlier, we are going to
devise a back-up plan which will consist in providing to Earth solar power energy and
light elements (such as helium-3), which will fulfill the Earths demand of energy.
In order to satisfy Earths high demand of energy we have thought of providing two
solutions.
Orbital Solar Power Satellites
We intend to create a space settlement which is going to provide energy to Earth.
Atmospheric absorption, clouds or nights are factors which do not affect sunlight at all in
space.
This way, seven times more power (both in space and along Earth) will be
generated. Using a microwave beam, the power ramp can be sent to a central solar
power satellite in orbit. The lack of carbon emissions or nuclear risks and the running
time of 100% represent the benefits provided by the orbital solar energy.
While it may be an efficient solution, there are also some disadvantages such as
the size of the collector on the ground is governed by the transmission wavelength and
the distance to the orbital station2. The use of shorter wavelengths or lower orbits can
somehow counter this.
In order to be convenient for Earth, the entire system must also be convenient ascost.
2http://en.wikibooks.org/wiki/Space_Transport_and_Engineering_Methods/Resource_Uses
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Nuclear Power
In order to obtain a stable and strong energy source, we have decided to choosethe nuclear option (nuclear fission and nuclear fusion). Although this seems to be the
best choice for us and for what we need, we cannot forget that a lot of disasters (such
as Chernobyl, Fukushima or the Three Mile Island) happened and will happen because
of the fission reactors. It is obvious that we cannot afford some kind of nuclear disaster,
but at the same time the nuclear option must be taken into consideration because of the
large amount of energy which can be obtained from it. That is why we made a short
presentation of how nuclear fusion and nuclear fission work.
It is important to know that nuclear fission is used by the nuclear reactors to
produce power. The way in which you obtain energy in nuclear fission consists in
splitting one atom into two atoms.
In the nuclear reactors from Earth, big amounts of energy are obtained from the
splitting of atoms of uranium (U-235, U-233), plutonium-239 and thorium-232. Apart
from these, radiations and radioactive wastes are also obtained. These wastes cause
serious damage to the environment because they last for a long period of time.
On the other hand, in nuclear fusion, the way in which you can obtain energy is
to join two atoms into one (it seems to be exactly the reaction which generates
hydrogen bombs and also the sun).The first argument for using this method is that it
does not produce radiations and radioactive wastes. Another good argument would be
that the elements used in nuclear fusion are easier to be found. So this method will be
much better than nuclear fission.
The best elements which are used in a nuclear fusion are Helium-3 in reaction
with Deuterium and Boron-11 in reaction with proton. Using Helium-3 produces more
energy and we intend to focus on the extraction and burning of the regolith from the
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Moon. By extracting regolith and burning it at 400 C we can collect H and He. After
collecting Helium-3 in special tubes, which will be transported to Earth, we can continue
burning the regolith in order to extract other materials for later use.
Tourism
Tourism may be one of the most important sources of making money for
colonizing the space. There are a lot of wealthy people on Earth who are going to pay
millions of dollars just to see their planet from orbit or just to go to the Moon or even toSelene.
It is known that some billionaires paid between 20 and 40 millions of dollars for a
stay of a couple days on ISS. Also, recent interviews show that a lot of Hollywood stars
are willing to have a holiday in space. This is a great business idea and a great
resource of money.
First of all, we need to explain our plan and some facts about space tourism, in
order to choose the type of spacecraft and the type of launch system that we are going
to use.
We are going to analyze what kind of spacecraft and launch system would be the
best for our business.
For a spacecraft we can use Orion built by Lockheed Martin for NASA, whichwas used for ISS astronauts transportation, or Soyuz, which was built for a lunar
mission, or even Dragon from SpaceX.
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The best choice for the launch system would be Atlas V, a rocket in two steps
which can carry a payload of over 20 tones. The first step is powered by RD-180
motors, using kerosene and oxygen as fuel, and the second step is powered by two RL-10 motors which are using the burning of hydrogen and oxygen.
The decision is to use a complex tourism plan on the Moon and another tourism
plan on Selene.
In the first phase a lunar module will be launched using a Falcon 9 rocket and a
propulsion module launched by Atlas V. These two lunar modules will couple on EarthsOrbit and will start their travel to the Moon where the lunar module will wait for the
tourists arrival. The tourists will be placed in a Dragon spacecraft which will be
launched using a Falcon rocket and which will be coupled with a propulsion module
launched by another Atlas V. When the Dragon spacecraft will arrive on the Moons
orbit it will couple with the lunar module and transfer the tourists. Then, the tourists will
descend on the Moon. After a while the Dragon mission will take them back to Earth.
We chose the Dragon spacecraft from SpaceX because it can be reused.
Dragon spacecraft, SpaceXSource:https://en.wikipedia.org/wiki/Dragon_%28spacecraft%29
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Today, the first phase would cost circa 6.4 billion of dollars, but it is presumed
that in the future it will cost less, somewhere near 0.5 billion of dollars.
The lunar module will have the capacity of two tourists and one astronaut. It will
be equipped with air tanks and pills for food.
We have not chosen a price for a ticket yet, but it can be estimated somewhere
about 0.75 billion of dollars. The price may seem high, but this project also needs profit
for further development.
To see more about how we arrive on the Moons orbit, check Appendix (A1) .
Short Presentation of the Lunar Base
This lunar base was conceived mainly in order to extract the needed resources
for the construction of the space settlement from the regolith (the land of the Moon), but
also for the facilitation of the space tourism.
For the astronauts teams that are going to supervise the activity of the tourists
and of some of the factories previously built on the Moon, we have to find a place with
natural protection. A good example would be the lava tubes, a safe place for humans
which is close to the craters (one of the places where the mining process will be
performed).
The electricity needed for the operation of this lunar base will be produced by
photovoltaic cells. These cells will be placed on the entire surface of the base.
Information like videos and messages will be transmitted to Selene or to Earth
through radars placed in the north of the base. The access to the radars consists in
specially designed roads.
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Our plan consists of going in a place in the space where we can obtain most of
the materials required for building the space settlement. We intend to do so becausebringing all the materials from Earth would cost too much and also it would take a lot of
time.
Taking into consideration the ideas from above, a very good location would be
the Moon, which would certainly help us a lot.
If we can bring mining robots on the Moon and start building factories and thensend materials to the location of Selene (defined in Chapter 3), we can say that we have
finished the most difficult part.
Also, a very important part of the development of our project is the construction
of the interior of the first space settlement. Selene will have an initial capacity of 200
humans, but in the future we are planning on extending it at a capacity of 2000 humans
and then to an even bigger number of 10000 humans (the process is explained in
Chapter 5).
After designing the first space settlement, we also thought of the idea of building
another one and colonizing the space and maybe other planets. In order to realize this
we will implement what we have learned from creating the first space settlement and to
apply the knowledge for the second, third and so on (there is also a chapter for this).
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III. Position in Space
In order to progress, it is not enough to act, we must know in which direction to act.
Gustavo Le Bon
3.1 Best Position in Space
Choosing the best position in space is one of the major decisions which must be
taken. Considering that our plan involves space colonization and making profit, we are
going to analyze the Earths orbit: Low Earth Orbit and Geostationary Earth Orbit, Lunar
Orbit and Lagrange Points (proposed in almost all the books referring to space
colonization).
We invite you to be part of our journey in which we are going to discover the best
positions using classical mechanics, Newtons Law, Keplers Law and mathematics.
3.2 Choosing the Position
First of all, we are going to analyze Low Earth Orbit (LEO). The distance fromthe sea level to LEO is d = 400 km.
For a circular orbit, the settlement should have a velocity equal with .For more details about v0 check Appendix (A2).
We consider:
G = 6.67384 10-11m kg-1s- (Gravitational constant)
M = 5.97219 1024 kg (Mass of the object; in this case, Earths mass)
R = 6,371 km (Earths radius)
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Knowing all these constants the velocity becomes:
Because the speed is an angular one, the energy received from the Sun cannot
be used efficiently. Another effect would be shorter days and nights, effect which will
obviously affect the health and activities of humans.
But we have to consider the fact that this velocity is too big and at the same time
too dangerous (including the big number of satellites and space debris which are placed
in LEO) for a space settlement.
If something wrong happens to Selene, it can become a great danger for Earth.
Another disadvantage is that it requires a big amount of energy for keeping it on the
orbit.
Other disadvantage may consist in the fact that up to now there has been no kind
of space exploration or mining which could sustain our plan.
Geostationary Earth Orbit (GEO) has the same disadvantages as LEO. Even if
the GEOs distance from the sea level is 35,786 km, this is not enough for supporting
our financial plan of space exploration and mining.
So, we have to analyze the next point, which is the Lunar Orbit.
We are going to analyze the Low Lunar Orbit (LLO), whose distance from the
Moon to its orbit is R = 100 km.
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To be sure that LLO is the best orbit for our space settlement, we are going to
calculate R using Kepler's Third Law:
The square of the orbital period of a planet is directly proportional to the cube of
the semi-major axis of its orbit.
We are going to use Newtons Law of Motion and Gravitation to get Keplers Law.
Because the Moon has a circular orbit, we can use the centrifugal force and
make it equal to the gravitational force:
(1) If we divide the first equation by m,we get:
(2)
Multiplying the second equation by :(1)
Considering (angular velocity), the result is:(1)
But ,where T is the orbital period of the Moon, equal to 27.321 days.
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Inserting this result in the fourth equation, we obtain a form of Keplers Third Law:
It results that:
Next, we have to calculate the velocity to maintain our space settlement on the
Moons circular orbit.
M = 7.34767309 10 kilograms (Moons mass)
T = 27.321 days (Orbital period of the Moon)
G = 6.67384 10-11m3kg-1s-2 (Gravitational constant)
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In order to obtain the velocity, we use again .We consider:
We get:
Taking into consideration the arguments above, we think that this is the perfect
place for the beginning of the development of Selene. We are going to build here the
first version of our space settlement. The construction of the space settlement will be
explained in Chapter 5.
Once the first version of Selene is complete, we will have to move to a newlocation, in order to expand our settlement.
To see the duration of the journey to Low Lunar Orbit check Appendix (A 3).
G = 6.67384 10-11m kg-1s- (Gravitational constant)
M = 7.34767309 1022kilograms (Moons mass)
d =1,738 km (Moons radius)
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We are going to choose one of the five Lagrange Points.
Joseph-Louis Lagrange (1736-1813), a French mathematician, discovered fivepoints around the Earth and the Moon where the gravitational forces acting on an object
are almost the same. That means that the netto forces acting on the object are equal to
0 and the object, with a negligible mass compared to Earths and the Moons, is able to
remain in the same position.
If we draw a straight line, we obtain the first three points which are going to beanalyzed. This means. .
The Lagrange pointsSource:http://en.wikipedia.org/wiki/File:Lagrange_points2.svg
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L1 would be the best solution taking into account the small distance between this
point, the Moon and Earth. However, there is also a disadvantage: the fact that, while
this point is a very good choice based on its property of being near the Moon, theGravitational attraction of the Moon can act on the object placed in point L1, and even
the smallest modification of the position of the object can be dangerous.
For L2 we have the same situation as for L1, which means that it is very likely for
a space settlement to be attracted by the Moon.
So, choosing the nearest ones to the Moon would be too dangerous. Consideringthe fact that later we will have to move the settlement at a new location, we are able to
give another argument of why we would not choose the positions close to the Moon.
L3 represents the other end of the straight line, and is located in the Sun-Earth
system, which is not very close to Earth, so we cannot choose this point.
It looks like we have to analyze L4 and L5 which form, each one of them, an
equilateral triangle with the Moon and Earth and are situated in perfect symmetry to the
axis Moon-Earth.
We are going to demonstrate that the triangle Moon-Earth-L4is equilateral.
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We noted the distance between A and B with d.
A = The center of Earth
B = The center of the Moon
D = The center of the Moons orbit
m = Moons mass
e = Earths mass
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The next step of our demonstration is to place our space settlement in L4 (point C).
We placed the space settlement in point C to be in equilibrium, which means that
it will keep the same distance to Earth and to the Moon. We assume that all the three
bodies have the same orbital period noted with T.
Because Selene, our space settlement, is motionless, it will have a centrifugal
force generated by the Moon and Earth.
The radius of the Moons rotation is and the space settlements radius is
R = CD.
The velocity of the Moonsrotation is vand the one of the settlement is .
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In this case, the distance is equal to the length of the circular orbit, which is for the space settlement and for the Moon.
From vT and dme vmT it results: and )
Equaling the equations we obtain:
(1) )The Moons centrifugal forceis equal to the attraction generated by Earth.
Dividing by :
(2) v Dividing by
and multiplying by
:
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Now we extract the square root and obtain:
(3) ) = Equaling (1) and (3) we get:
(4)
Next step in our demonstration is the equality between the centrifugal force of our
space settlement and the attraction of the Moon and Earth.
and
s = Mass of the space settlement
Fe =Attraction force acting from Earth to our space settlement
Fm = Force acting from the Moon
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Because we must use the components of the forces from the line CD we obtain:
c o s cosDividing by s:
(5) c o s cos
Squaring the 4th
equation and multiplying by R we get:
(6)
Equaling the 5thand the 6thequation the result is:
c o s cos We divide the previous equation by Ge:
cos cos
When we started our demonstration we noted d me x , and by inserting it inthe last equation we get:(7)
cos cos
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We also know that:
s i n sinDividing both equations by Gs: s i n sin
Rewriting the last equation in another form:
Inserting this equation in the 7thequation:
cos cos
Doing some calculations:
(8) Knowing the law of sines:
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We apply it in the triangle BCD, where DB = x and CD = R:
Inserting this result in the 8thequation and simplifying by sin:
sin
sin
sinsin Applying the same law of sines in triangle ABC, where AC = b and AB = d:
sin
sin
Equaling the last equation above with the last equation from the previous
paragraph:
Taking all these into account and changing the position between m and e, we
conclude that d = c, so the triangle ABCis an equilateralone.
In conclusion, the position in which we can place Selene, the first space
settlement, is the Lagrange L4 orL5. We chose to place Selene in L5.
Other positions in space will be discussed in the 11 th chapter, where we are going
to develop idea of building more space settlements.
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3.3 Advantages and Disadvantages
Until now, we have chosen two positions for Selene, our space settlement. Next,
we are going to present the advantages and the disadvantages for each of them.
We decided to start with the lunar orbit. This first place represents a start ramp,
taking into account that we are constructing Selene with materials found and mined on
the Moon. A small distance and a low escape velocity (2.4 km/ s) represent two of the
biggest advantages. This advantage will consist in the fact that our space settlement
would be built faster than if it were built at a bigger distance (for example, L5). Also,
placing Selene on the lunar orbit is the first phase of our project. The second phase is
moving it to L5.
Moved to L5, Selene can easily start its life as a real space settlement, which will
be able to colonize the space. L5has lots of advantages:
Material supplyeven if we move from the lunar orbit, we are depending on the
Moons resources, which will still have an important role. By mining the Moon,asteroids and comets, it is possible to upgrade our space settlement at the
second phase.
Stabilitywe have demonstrated that an object placed in L 5or L4remains in the
same position. However, the Sun was not involved in our demonstration.
Fortunately, its attraction is not dangerous and it can be corrected by using
motors to maintain Selene in equilibrium.
Energy a settlement placed in an area where the solar power has maximum
efficiency produces a lot of energy. However, this also represents a disadvantage
which can be minimized by using the best material, such as RXF1, an anti-solar
wind shield or other kind of radiations which may come from the Sun.
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Taking all these into consideration, we are going to use the Lunar Orbit for the
first phase and in the next phase we will move to L5.
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IV. Mining the Space
At the source of all knowledge, we find curiosity! It is an essential condition for
progress.
Alexandra David-Neel
4.1 Mining the Moon
The Moon is the first source of materials for building Selene. We chose it for its
properties and the relative small distance toward Earth, the second source of materials.
Mining the Moon will not be easy, but we are sure we can do it. We consider that
humanity has accumulated a very big knowledge in the last century as far as
astronomy, astrophysics, aeronautics and technology are concerned. The current
knowledge we have in technology would make the returning of humans easier and less
expensive than it was in 1969 when the first man landed on the Moons surface.
However, our plan consists in sending robots to the Moon for mining, robots
which will be controlled from Earth. This is an important decision which can affect or not
the mining process.
Sending humans to the Moon would be too dangerous, taking into account the
big number of radiations that hit it and also the fact that the Moon does not have a
magnetic field to protect itself. Because of this, a lot of mutations of DNA may result.
Another disadvantage of sending humans on the Moon would be the fuel required for
sending them back on Earth, fuel that will obviously occupy a big part of the capacity of
the spaceships. Considering all the above, we can conclude that humans cannot be
sent on the Moon, so we have to send robots.
One of the most important advantages of the robots would be that, once they are
sent on the Moon, they do not have to return to Earth. Another advantage is that they
can be operated continuously by telecommunication directly from Earth. That may
sound crazy, but it is possible, because the delay between the Moon and the Earth is
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represented by only three seconds. And if for some operations the delay is regarded as
a disadvantage, robots can also be programmed directly from the Earth.
Radar placed on the Lunar Base (receives commands from Earth)
Another advantage of using robots would be the big quantity of payload that they
can carry to the base. We should not forget that the more they carry, the stronger they
should be. Also, robots can operate in dangerous areas where human beings cannot.
Last but not least, robots need only energy to function instead of humans who need air,
water and food. These human needs would be too difficult to afford during a mining
process, and that is why robots would definitely do a better job. Taking into account all
the arguments above, we decided that humans would be employed to work only on
Earth.
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So How Does It All Start?
We have to think about the robotsappearance, what functions they should have
and how they will explore the Moon.
First of all, we start by explaining their technical specifications. Robots will be
equipped with cameras, drills, robotic arms with tactile feedback, and wheels for
locomotion. They will be also equipped with spectrometers for on-site mineral analyses.
We should not forget the solar panels placed on the upper side of the robots, which will
convert the energy sent from the Sun to electricity, the fuel of the robots. Another fact
is that the robots sent to the Moon for mining must be adapted at temperatures between-173 and +127 . For this, materials like Ultra High Temperature Ceramics (UHTC),
developed by NASA, and a strength polymer like M5 Fiber will be used in the robots
construction. Also, we have to consider the Moons gravitation which is of Earths
gravitation. That means that normal mining will not work so well on the Moon, but, it is
known that every project and experiment has a start, so engineers will have to improve
Earths mining techniques and adapt them tothe Moons environment.
When robots arrive on the Moon for the first time, they will have batteries which
will ensure their energy for two weeks. Their energy will be composed by the energy
provided by the batteries plus the solar energy which will be stored. Using this
technique, it results that the robots will have energy for four weeks. Why? Because the
Moons day is approximately 29 days, and robots will be sent on the Moon during the
day, and not during the night, which has the same duration as the Moons day.
In this time the robots have to build the lunar base. We found out that a good
location would be represented by the lava tubes which ensure the protection against
solar wind. After that, the next operation will be represented by finding the site where
they will extract regolith. After extracting the regolith, they will carry it to the base. There,
after doing some chemical reactions, other robots can start extracting from it different
materials and produce in factories solar panels and components for the next robots. The
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regolith properties and the factories that should be built will be discussed later in this
chapter.
On Earth, there should be more bases where specially trained operators will
control the robots. We thought that it would be a good idea to steam videos in real time
to the World Wide Web presenting the activity which will take place on the Moon.
In order to broadcast images to Earth, we thought that it would be very useful to
position AERcam-Sprint at the sites and at the lunar base for better and multiple angles
of view.
In order to obtain the perfect robots which are going to build the base and
factories, a number of 20-30 prototype robots from each category like drilling robots,exploring robots or transporting robots should be sent to the Moon. These prototype
robots are mandatory because we cannot predict how the first robots will adapt to the
Moons conditions. This has never been done before, so we have to understand each
system of the robots and then build more complex robots.
AERcam-SprintSource:http://er.jsc.nasa.gov/seh/AERCAM/aercam.htm
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Our idea is to organize an international contest about robots. At this contest
teams from all countries of the world can participate, but our main purpose is to invite
students from the most well-known Universities all over the world, who are studyingrobotic engineering. This way, we can prepare the new generation of engineers who will
have the knowledge and experience to build robots for colonizing the space. Also, we
can use the concepts for creating robots of the best teams.
What Kind of Robots Should We Have?
The most important categories of robots which should be projected and sent on
the Moon are:
1. Robots for excavations
2. Robots for carrying
3. Robots for building
All the robots will be equipped with solar panels and will be controlled from Earth.
Excavation robot prototype
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Carrying robot prototype
Building robot prototype
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The first spaceships sent to the Moon will be equipped with robots like the ones
presented earlier, but also with a chemical reactor and a chemical manufactory which
will manufacture methane and oxygen.
Lunar Materials and Factories
As far as lunar materials and factories are concerned, it is important to start with
a brief introduction referring to the minerals that are going to be mined.
It is known that pure iron and aluminum, two of the most important materials,
cannot be dug out directly from the regolith.
Aluminum (noted with Al) can be found on the Moon in a mineral called
anorthite (CaAl2Si2O8). Anorthite is a mineral which contains 20% aluminum and can be
compared with the Bauxite ore used for extracting aluminum on Earth. Aluminum is an
important resource and has a lot of utilizations. It can be used for electrical conductors,
because it is known that the Moon does not provide considerable cooper minerals. Also,
from aluminum we can build reflecting mirrors. It will be also used during the
construction of the parts of the buildings from Selene (doors, windows, household
items). Atomized aluminum burned with oxygen produces fuel which can be used for
spaceships and rockets. For robots and for the rocket construction there can also be
used aluminum, taking into consideration its high resistance, malleability and the
relatively low weight (compared to the weight of the iron or copper, for example).
Using it for electrical conductors may be useful for communication on Selene.
The reflecting mirrors are part of solar ovens and can be used for melting
metals and for the Termite Reaction.
However, there is a disadvantage which should be considered. According to the
temperature, aluminum changes its size (dilatation and contraction). Because of this, we
cannot use it for building large structures. In this case, we are forced to use other
materials, such as iron (steel) for this kind of structures.
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Calcium(noted with Ca) is also an abundant element on the Moon and can be
extracted with Aluminum from the anorthite. It cannot be used for construction, but it can
be used for ceramics. Also, calcium can be used as an electric conductor, taking intoconsideration the fact that it can be easily modeled, pressed and then transformed in
wires, but only on the Moon where it does not encounter oxygen particles. Its capacity
of conducting the electricity is twice and a half bigger than aluminums and coppers.
However, calcium is not a very strong material and that is why it is not recommended to
be used in constructions.
Silicon(noted with Si) is the second most common element which can be found
on the Moon (after oxygen). Silicon can be very useful for the development of the
settlement, considering its characteristics which allow silicon to be used for the
obtaining of solar power cells and different types of glass. From Si the primary oxide
which is obtained is silica (SiO2). From silica combined with sodium results the glass
used for mirrors on Earth and also, combined with boron, results high quality glass,
usually used for heating and cooling devices.
Titanium (noted with Ti) is a light and strength element which can be easily
found on the Moon. The Apollo missions found it in Ilmenite ores, FeTiO 3. In this ore,
TiO2 is found in a big concentration of about 55% of the ore. TiO2 may be used for
obtaining white papers and plastics. We can use Titanium for shielding, for different
means of transport and for constructions. Moreover, it can be used as a substituent for
the silica in order to obtain photo electrochemical cells. It can be extracted using
Ilmenite Reduction.
Iron (noted withFe) is one of the most abundant elements on the Moon. It can
be found and extracted from Ilmenite. From Iron alloyed with Carbon we can produce
Steel. Steel and Iron are definitely used for Selenes construction, for robots
construction and for different buildings.
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The thermite reaction is a very important one. It is a reversible process, like most
reactions, and gives off large amounts of heat:
Al2O3 + 2Fe + energy 2Al + Fe2O3
This reaction both gives and takes heat so I can be used for both purposes. Also,
because of the reversibility of the reaction, we can always control the amounts of pure
iron and pure aluminum that we have.
Another way to obtain iron is from ilmenite, a mineral the moon is rich in. Iron can
be extracted from ilmenite by hydrogen reduction.
FeTiO3+ H2 Fe + TiO2+ H2O
The obtained water can be then electrolyzed into oxygen and hydrogen. The
obtained hydrogen can be used to repeat the reaction and the oxygen can be used as
an emergency atmosphere regulator.
The titanium can then be extracted using a relatively simple procedure.
TiO2 + 2Cl2+ 2C TiCl4+ 2CO
TiCl4+ 4Na Ti + 4NaCl
The resulting sodium clohride can be used in food and the CO will quickly
trnsform into CO2which can be converted to oxygen with photosynthesis. Titanium is a
very strong material and can be use din construction infrastructures.
Silicon can also be extracted from the moon in the form of SiO2. Silicon can be
used an an abrasive, can be polymerized in order to patch up holes and can be used tomake glass.
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4.2 Mining the NEO
First of all we have to introduce the NEO abbreviation. It stands for Near Earth
Objects. NEO refers mainly to the asteroids and comets which are found in our Solar
System.
Because we can only mine the Moon crust which is not very rich in metal, we had
to find a solution. So we thought of using the raw materials which can easily be
extracted from asteroids.
Asteroids can be found in a big number near Earth (approximately 200 000 of
asteroids with a diameter larger than 100 meters).
For the first settlement, Selene, we will use only the asteroids which are near
Earth, but for the next space settlements, we will obviously make use of the plenty of
asteroids which can be found in Space (for example, the belt of asteroids between Mars
and Jupiter).
Mining the asteroids has many advantages: various resources can easily be
obtained and extracted, the costs of manufacturing and transportation are low, almostequal to zero and this process can never be risky. There are lots of types of asteroids
and each of them can be used for obtaining different raw materials or resources.
The main categories of asteroids which held our attention are:
1. Carbonaceous Chondrite Asteroids
These asteroids represent only a small part of the total number of meteorites. They
are rich in water, hydrogen, oxygen, sulfides, and other volatile organic chemicals. Theyare divided into several groups, each type having a different structure. The most notable
are:
a. CI group: named after Ivuna meteorite. These asteroids consist of 22% water,
the rest being amino acids, as well as polycyclic aromatic hydrocarbons.
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b. CV group: this group has taken its name from Vigarano. Such chondrites present
low metamorphism and minerals such as pyroxene and olivine can provide awide range of compositions, showing that they have formed into various
conditions in a solar nebula.
c. CM group: named after Mighei, they are known to contain large quantities of
organic compounds, such as purine and pyrimidine nucleobases and also amino
acids.
d. CR group : this type of chondrites present a uniquely large variety of minerals,
containing up to 60 different substances, some of which have not been found
anywhere else in nature.
e. CH group: H chondrites, coming from high metal , contain up to 40% metal,
which makes them the richest of the chondrite groups. They are structurally
related to the CR and CB groups.
f. CB group: this group takes its name from its most representative member:
Bencubbin. They contain over 50% of nickel-iron metal, being chemically related
with CR chondrites.
Carbonaceous Chondrites are extremely important, representing a considerable
source of fuel. One average meteorite, only 75 meters in diameter, could supply the fuelnecessary for over 135 space missions.
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2. LL Chondrite Asteroids
These kinds of asteroids are maybe the most important as far as the metal
extraction is concerned. Even the name, which is an abbreviation which stands for low
iron, low metal points to the fact they contain more than 22% iron, but only a small
percentage of pure metal (1-3%). That is why they are not very attracted by magnets.
The LL Chondrite asteroids are rich in Platinum group metals (PGM).
There have been discovered over 2.500 near-Earth asteroids which are over 500
meters in diameter. Studies have shown that a PGM rich asteroid which is about 500
meters in diameter contains more platinum than it has been mined ever since the
beginning of humanity.
As previously mentioned, the extraction and transportation of near Earth
asteroidal material has important benefits.
Because the asteroids have too big sizes, we would not bring a whole asteroid to
Earths orbit for the extraction, but we will scoop up only the material that is needed.
Then it will be refined and the material obtained after this process will be sent to thespace settlement. Obviously, the size of the payload is way smaller than the size of the
asteroids and that is why the energy required by the transportation is very small, almost
null. This represents a major advantage for which we are mining the asteroids- while
making savings in the costs of transportation, we obtain a lot more material. Moreover,
obtaining materials from asteroids does not involve any risk of crashes during
transportations and huge rockets are not required, due to the fact that the asteroid s
gravity can be neglected.
Briefly, the process of obtaining useful material from asteroids consists of solar
oven casting, sintering (or some other forming) and industrial means of manufacturing.
So-obtained materials can be used in constructions (example: alloys of Ni, Co
and Fe). The contained dirt and slag can be used as shields against space radiation.
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Ceramic objects like sinks, pipes or even walls and structures can also be obtained by
melting this dirt and slag in solar ovens at very high temperatures. The dirt also contains
oxygen, which should be considered for further use.
Another advantage is the obtaining of a very cheap and in big quantities fuel from
asteroidal material. The most commonly used fuel on this kind of interspatial expeditions
is hydrogen which is burnt with oxygen inside the rockets. This fuel is obtained by
splitting water apart in order to make pure hydrogen and pure oxygen, which then make
vapors which lead to the propulsion of the rocket. An alternative to this fuel is the
hydrocarbon fuel, taking into consideration the fact that carbon is also a commonly
encountered element in the composition of asteroids.
Also, we are considering the extraction of precious metals (like platinum, iridium
or cobalt) from the asteroids. They can be extracted with an easy technique called
Carbonyl process, which separates iron, nickel, cobalt and the other metals in a very
nice way.
Which Are the Conditions to Mine an Asteroid?
The size of an asteroid changes from one to another, ranging from small ones to
some which can resemble with rugby stadiums for instance and they contain large
quantities of material up to 30 million tons. The gravity is not a downside like some
people liked to believe due to the fact that is almost 0, practically inexistent compared to
the Moon, so the only thing we are concerned about is how to deal with mining and the
operations implied. We can distinguish three cases here:
1. A lot of attempts were tried in order to find out which was the best solution to
exploit an asteroid. One solution is to attach equipment which uses solar power
on the asteroid with the condition to face the sun. However, this method is not
always applicable. For instance you can only use it when the size of the asteroid
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is not very big and you can prevent it easily from spinning. Another disadvantage
is that the process implies a lot of money being spent on fuel.
2. The second method is better because it does not imply fuel and it is cheaper. It
uses the so-called yoyo-like gadget. One problem which can occur can be the
length of the string, because it is strongly related to the size and the mass of the
asteroid we are working on. But we must remember that the velocity is ignored,
not influencing the process. If this method is chosen, the mathematical calculus
must be precise and accurate before actually proceeding.
3. The third method is to let things go normal, not to stop the spin of the asteroid,but only when you have to deal with big asteroids or small ones when the budget
is limited.
Required Equipment and How to Actually Process the Mining Materials;
Challenges Implied by Space Mining
In order to be able to get in possession of the endless resources from theasteroid, we need to know perfectly what to do right from the beginning. The equipment
plays a vital role in this process. An advantageous aspect is that you can reuse the
equipment on more asteroids. The people accredited in this field want to replace the
humans with robots, as long as it is possible. But if they want to send humans in space
to facilitate the process, the first step they do is to send the equipment before and after
they arrive at their destination, so that everything is prepared for the people to finally go.
The most challenging fact about space mining is bringing the concept fromscience fiction to reality and, in order to do so, the infrastructure plays a vital role. First
of all, all the development methods must be tested within a long period ago. The human
being will definitely be replaced by the robot which will make almost all the jobs. That is
why we must create a machine which is able to convert for instance the floating piles of
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rock into raw material. Another challenge is to find out how to use local raw materials to
develop a propulsion system.
Providing the equipment required by this process is way easier than we firstly
imagined. The only thing we should be concerned about is how to actually process the
material which is a complex activity, because it implies chemical phenomena and
mechanical grinders.
Spacecraft to Analyze the Asteroids
Knowing how to build if not the best spacecraft at least a very good one plays a
vital role. The increasing necessity to exploit an asteroid raised a lot of questions and
problems. We must be able to make the best choice in order to be fully efficient and the
choice of the optimal target is extremely important. On the other hand, we must take
into consideration the fact that in the past few years, the costs implied by the
construction of such devices were opposite to the performance which was growing day
by day.
However, we must find out a method which simplifies our calculations and
maximizes our potentials and chances to succeed by making something which is
capable of ensuring a mass production. The design must be complex but equally
simple. For instance, the system must not be big or weighty. But on the other hand, how
to do this without the risk of missing something compulsory for our mission? The answer
is simple: we eliminate the parts which are not important by adding extra characteristics
to other systems to multiply their usage.
Also, the communication system is not negligible, due to the fact that if the
operation is conducted by humans they must keep in touch with the people monitoring
the activity. Only like this they can call for help if something does not work properly or as
intended, you can never know what can go wrong during your expedition and an
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antenna can occupy a significant surface which we want to avoid in order to effectively
use our limited space.
These having been said we can distinguish the following two cases:
1. Sending the data to be analyzed on Earth
2. Analyzing on the spot and sending only the report to Earth
We can easily see that the first method is not viable because building a
spacecraft implies a huge budget and the fuel is expensive. Also, it is slow and not
efficient to make two runs while the second one will have the same achievements and
will consume half of the fuel. We must also make a decision on what purpose the
spacecraft will serve. For instance, we have to decide if it analyzes small asteroids
which have a big velocity or big ones where the velocity is almost inexistent. These are
facts which can simplify or complicate the task.
If the result of the analysis is positive, that means the asteroid is viable: the
shape, composition and dimensions are all perfect and we can finally commence the
mining. The capacity of a robot must be as big as possible, so, after consuming anasteroid, the robot is able to move to a next asteroid.
If we do not have the possibility to choose the second case, we can at least send
a stationary spacecraft which will come back on Earth after gathering data from more
asteroids. Then, the spacecraft will present the final results and the decision for mining.
Like this, even in this case, we will have a mission success.
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V. Space Travel and Construction
You have to know the limits of the possible. Not so that you can stop yourself, but so
that you can attempt the impossible under the most favorable conditions.
Romain Gary
5.1 Propulsion Systems
For Selenes propulsion system, the jet propulsion will be used, the kind of
propulsion which is also found at rocket motors.
What Do We Need Propulsion for?
First of all, we need it to adjust and maintain the position and the orbit of Selene
in L5. Our demonstration from Chapter 3 contains in its rationality just the Moons and
the Earths gravitational attraction, but it does not include the Suns gravitational
attraction, which may disturb Selenes stable position. So for keeping the Space
Settlement in a stable orbit, it is mandatory to implement a propulsion system.
Another reason would be the changing of position from Low Lunar Orbit to L5.
More precisely, Selene needs a propulsion system for:
interplanetary travel
orbit control
altitude control
What Kind of Propulsion Systems Should be Used?
By the type of energy source, there can be implemented three propulsion
systems:
1) Chemical propulsion uses chemical reactions combined with heat to
generate gasses at a high temperature and at very high pressure. These
gasses are ejected and produce a thrust force;
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2) Electric propulsionuses electricity for ejecting the matter in order to produce
a thrust force;
3) Nuclear propulsion uses nuclear reactors which accelerate heated gassesand then eject the gasses in order to produce a thrust force;
The basic equation for Force of Thrust is:
[] (
is the mass flow rate of propellant and is the propellant exhaust velocity)
The basic equation was rewritten by Tiolkovsky and obtained the Basic Rocket
Equation:
The propulsion performance factors can be determined using the thruster-
specific Impulse:
Because it is too difficult and too expensive to obtain big amounts of fuel for
chemical propulsion and the nuclear propulsion also looks very instable, Selene is going
to have a propulsion system based on electricity.
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5.2 Expansibility Principle
It is obvious that sending 10000 people from the first time on Selene would not
be achievable. It is impossible to send such a big amount of people and expect
everything to be fine.
Our team suggests starting with an amount of only 200 people when Selene is
built on the Low Lunar Orbit. When the settlement will be moved to L5we intend to grow
the population from 200 to 2000 people.
Being at L5, the population should grow in two-three decades from 2000 people
to 10000 people.
But How Does this Growth Happen?
First of all, we have to affirm that the size of Selene will change in time. Firstly,
we want to start with a small space settlement, at which we extend the core and add
new modules. This process will be better understood in the next section.
Changing the sizes takes time and work, but this is the only way in which Selene
can grow and support a big number of people.
So, the growth of the population will happen by expanding the space capacity.
This way, new settlers will be able to come from Earth or even be born on Selene.
5.3 Structure and Aspect of the Space Settlement
Our colony will be organized and divided into six small towns; each of them is the
living space for 1650 colonists. Every town is represented as a component, which is
added to the main torus. All the buildings have the same design in all the towns in order
to avoid conflicts between settlers, when they choose in which one to live.
There are four types of houses which will be built of fire resistant materials.
According to the space which is provided by a house, they can be divided in: houses
only for a settler, for two settlers (with possibility of adding another component in case
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that there is a baby), for a family and residential houses. For each settler, a space of 40
m2will be assigned.
But even with this similarity among the six towns, there is a remarkable
difference between them. This difference consists in the kind of activities which will be
held in each town.
The first town, called the town of science, will have libraries and the center of the
educational system. Here settlers from other towns can come and attend courses or just
relax while reading a book. The majority of the settlers who live here are from the
engineering or academic fields.
The second town, called the town of relaxation, will have hotels, spa centers,
parks and theaters. In this town settlers will be able to relax after a hard day, have a
walk, practice a sport or laugh when they watch a comedy played at the theater.
The third town, called the town of administration, will have all the government
buildings. Also, this town can be considered the center of political and administrative
activities. In this town, you are allowed to live only if you work in the administrative
offices. Usually, normal settlers will not have why to come here or maybe just if they
commit a crime, but there are little chances for this to happen.
The fourth town is called the town of health. Here, the medical system is going to
be the main activity. Settlers with different diseases can come here and get a treatment
in order to become healthy again. Also, the majority of the settlers who are living here
will be doctors or engineers.
The fifth town is called the town of industry. By the name of this town, Selenesindustry is going to be the main activity in it. It is obviously that a big part of the settlers
who live in this town will be engineers.
The sixth town is called the town of parties and shopping. Students and usually
young people will live here, but every settler who wants to have fun at a party or to
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celebrate an event in their life can do it in this town. Also, it is the ideal place for
shopping: clothes, decorating objects and jewels can be bought from the built-here mall.
More precisely, the structure of the settlement consists of:
a main torus
six modules in hexagonal shape
a dock sphere
The main torus has an important role for transportation and for construction. First
of all, a high-speed maglev train will be placed inside this torus. This non-contact and
electric powered train has a method of propulsion that utilizesmagnetic
levitationtopropel the vehicle withmagnets. This mean of transport will represent the
main one on Selene. Secondly, the main torus will act as a core: the six modules will be
attached to the torus in order to obtain the space settlement.
The dock sphere will have four docks for spaceships. It will be connected to the
rest of the settlement by cylinder bridges, which will help the visitors and settlers to be
transported from the docks to the third town. Here, they will be registered and identified.
Next, they will be transported to their hotels from the second town. In the dock sphere
there will also be a special room, for accommodation. At first, there will not be any
atmospheric pressure, but an intelligent system will adjust it until the pressure from the
room becomes equal to the pressure of Selene and of the bridges.
The cylinder bridges will help the main torus spin in order to obtain the artificial
gravity required by the towns. In the center of the docking sphere we intend to constructa powerful machine based on bearings which rotates the main torus and divides the
dock sphere into two parts: the top and the bottom one. As far as transportation is
concerned, the departure of the settlers will be made from the center of the docking
sphere.
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Also, a 0G (zero gravity) room will be placed in the docking sphere for
entertainment.
For the day/night cycle Selene is equipped with big mirrors placed above at a
distance of 350 m and at a 45 angle.
As stated before, the modules attached to the main torus have a hexagonal
shape. The length of each of the six sides of a hexagon is 550 m. This means that the
surface of a hexagon is:
The total surface is:
The projected area is:
The height of each module is 50 m so the total volume is:
Structural mass at 1/2 atmosphere= 313. 6 kt
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The following table represents the estimated distribution of the space on the
space settlement.
Use of space
Surface
(m/ person)
Number of
levels
Projected area
(m/ person)
Estimated
height
(m)
Volume
(m3)
Residential
areas
108 4 27 3 324
Commercial
areas
4. 3 2 2. 3 4 17.2
Offices 1. 5 3 0. 5 4 6
Hospitals and
clinics
0. 6 3 0. 6 5 3
Schools 1. 5 3 0. 5 4 6
Churches 1. 5 1 1. 5 10 15
Recreation andentertainment
6 1 6 3 18
Public open
space
20 1 20 50 1000
Industry 44 2 22 7 42
Transportation 3 1 3 6 18
Communication
equipment
0. 5 1 0. 5 4 2
Water treatment 4 1 4 4 16
Electrical
distribution
0. 1 1 0. 1 4 0. 4
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Miscellaneous 2. 9 3 1 3.8 11.2
Farm 24 1 24 5 120
Storage 40 2 20 10 400
Totals 262 - 133 - 2107
Construction
The First Phase (20452050)
The first phase of creating the space settlement consists of building the main
torus. This first phase will take part at the Low Lunar Orbit. Ships and robots will start
building the main torus using materials extracted from the Moons surface. After that ,
two hundred settlers can be sent from Earth to Selene and contribute to the process of
building the inside of the settlement. Also, the dock sphere has to be constructed in the
same time with the main torus.
The cylinder bridges will be built in order to connect the dock sphere to the main
torus. We do not have to forget about the machinery which rotates the torus.
We assume a period of five years for constructing this phase.
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The settlement after the first phase
The Second Phase (20502057)
The second phase of the construction consists of building two towns and moving
the settlement to L5. During the second phase, we intend to grow the population to 2000
settlers.
In this time, the industry and diplomatic sector will be developed. Houses, shops
and the transportation system have to be constructed in order to offer a good life quality
for the settlers. To achieve more resistance, we intend to add strong iron tubes between
the two towns at the top and bottom side.
For the construction of the second phase, we assume a period of seven years.
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The settlement after the second phase
The Third Phase (20572067)
In this phase, we suppose that Selene will be extended at its full capacity of
10,000 settlers. Between the second and the third phase, other four hexagonal modules
will be added to the main torus.
Also, all the towns will be developed in order to provide a high living standard.
Different types of buildings will be constructed. During the building process, robots and
humans will work together for a faster productivity.
In this time all the sensors needed for protection, air purification, hole detection and
water recycling will be mounted. In order to ensure the safety of the settlement, sensorsfor fire detection and water flooding will be spread on its entire surface.
The infrastructure of the medical system, educational system, industry and food
production system will be highly improved in order to satisfy 10, 000 settlers.
We suppose that the third phase will take approximately 10 years.
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The settlement after the third phase
5.4 Artificial gravity
5.4.1 Why Do We Need Gravity?
Medical studies revealed that longer exposure in an atmosphere free space
could lead to osteoporosis and very low resistance to any bone impact. In addition to
that, given the fact that the body draws calcium from the bones to correct electrolyte
imbalances, it is clear that several weeks and months spent at zero g will lead to a new
balance in cellular fluid. Like this, the electrolyte balance may not be achieved.
Moreover, hormonal imbalances also persist. In other phases of missions, more
symptoms were noticed: suppression of the excretion of steroid hormones, reduced
production of norepinephrine, indications of hypoglycemia and corresponding increase
of the primary hormones.
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Also, when returning from zero g to Earth may appear medical problems, such as
increased heart rate, changes in muscle reflexes or leukocytosis.
Although physiological changes were reversible, it is unknown whether this will
be possible after a prolonged weightlessness. Vascular changes or changes such as
decreased immunity and fetal developmental differences may become irreversible.
Given the current knowledge on the effects of weightlessness, it seems
appropriate thata certain level of gravity should act on humans for most of the time.
Lower levels than one g cannot be considered because there is a lot of unknown
information about the consequences of long-term exposure to levels of gravity between
zero g and one g.
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The centrifugal force will play the role of gravity:
Thus,
and
For the each hexagon we have:
We intend to obtain:
Which leads to:
= 1.059 rpm
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The angular velocity of the settlement will be 0.1109 radians/ second and the
structure will do one full rotation in almost 56.62 seconds.
Now, we know our angular velocity. By deciding the acceleration at the points
situated at the intersection of the surface of the sphere with a plane perpendicular to the
axis of rotation and which goes through its center, it will be easier for us to find out the
radius of the sphere.
= 406 mRotation can be an easy way of achieving gravity. One thing we may easily miss
when talking about this is that, during the rotation, the axis of rotation must be
perpendicular to the axis of maximum angular inertia. Factors from space, such as small
objects hitting the construction, large objects passing by and interacting with the
settlement may cause the change of the axis of rotation. Therefore, the settlement will
wobble and become partly unstable for a shorter or longer period of time, according to
the deviation of axis.
This problem can be solved by using an intelligent weight distribution system.
Sensors will be placed in key parts of the settlement, at the surface of the construction,
allowing us to create a map of weight distribution. Data will be collected in real time on a
computer and, when any event that may cause the change of the rotation axis of the
settlement, the computer will notice this.
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For corrections, there will be a system of cables and weights attached to the
main torus, one weight for every 15 degrees of rotation. By adjusting the cable lengths,
the mass center will change, thus allowing the settlement to revert its position ofstability. Calculations will be done in real time, 24 hours a day, in order to ensure
complete stability.
5.5 Shielding
5.5.1 Cosmic Radiations
Similar to the inhabitants of Earth, the settlers of Selene and the rest of the
creatures are subjects to radiation. Protection against exposure to radiation is achieved
by minimizing the exposure time and the distance from the source, as well as by using
protective equipment.
Radiation consists in electromagnetic waves of high energy (radiation x, gamma
rays) or particles (alpha, beta, neutrons).
Ionizing radiation damages the tissues in different ways, depending on the
amount of radiation and the amount and extension of exposure. Ionizing radiations
affect messenger RNA, DNA and the production of free radicals in other reagents. Big
amounts of ionizing radiation may cause death, while low doses affect cell proliferation.
Genetic effects consist of malignant transformation or hereditary genetic defects.
Children are more susceptible to radiation, because they have a high rate of cell
proliferation and an increased number of subsequent cell divisions.
Radioactive elements can reach water, food and building materials, while
animals can also be contaminated. Therefore, when there is an increase of the amount
of cosmic radiation, drugs and chemicals (sulfhydryl compounds) may be administered
to animals and, if given in time, they will increase the survival rate of animals. However,
these drugs cannot be used on humans.
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Considering the powerful effects of neutron radiation on the human body and the
living environment that we created on Selene, it is imperative tobuild a protective shield
for shielding it against contamination coming from the cosmic rays.
Based on the U.S. Federal Government standards for the terrestrial environment,
we need a shield which can bring the radiation level toa value lower than 0.5 rem/ year.
It can be estimated that the amount of sunlight that our space settlement
receives from the Sun is equal to approximately 2 kW/ m2 per day. This represents
almost three times the amount of sunlight received on Earth (747 W/m2per day).
Taking into consideration the total surface of the settlement (4.7 x 106 m2) and
the amount of sunlight (2 kW/ m2/ day), it results a total of 940 x 107 W. The value which
is normal and should not be blocked by the shield is 351 x 107 W. Regarding this
calculations, it is obvious that a big amount of energy (589 * 107 W) has to be blocked.
5.5.2 Choosing the Shield
For creating a good shield, we had to choose between a passive shield and one
generated by a magnetic field. In our case, a passive shield can be very helpful
because it absorbs the radiation rays. But for constructing it, a big amount of regolith or
other protective materials should be used. So we switched our attention to generating a
magnetic field.
Earth has a magnetic field and has been using it for millions of years. While
Selene tries to have most of the qualities that Earth has, creating a magnetic field in
order to shield the space settlement seems to be the best way of doing it.
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Since the total energy that must be rejected is 589 * 107 w, and the energy of a
magnetic field per unit volume is
, for the total volume of Selene it results
.This way, =0.003238 Tesla.
Using the magnetic flux density we can easily calculate the Lorentz Force:
A is the total surface of Selene and L is the total Length. Inserting them in the last
equality, the intensity of current is and it is equal to 305 x 103A.Taking into account the results obtained, we get the shielding method: we will
generate a magnetic field of certain intensity (305 x 103A).
B = Magnetic flux density
V = 14.1 108m3(Volume of Selene)
= 4 107N A2 Ma netic ermeabilit of s ace
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VI. Human Needs and Factors
To deal with individual human needs at the everyday level can be noble sometimes.
Jimmy Carter
6.1 Food
6.1.1 Nutrition
Nutrition plays a vital role in our daily shift due to the fact that our body needs
constant fuel which is the food and as regular as possible and when really needed and
maintenance mustnt be neglected because sports exercise or mental attitude for
instance aid us in the process of achieving a health potential.
A perfect nutrition can have the following consequences:
1. Improves all your performances ranging from sports to mental activity
2. Gives us the power to continue our activities, preventing us from tiredness
and stress, but not in all the cases
3. Boosts all the abilities to remain focused, concentrated and calm when
dealing with difficult projects, situations etc.
4. Reinforces our immunity system
A way to achieve all of the above mentioned is to eat less sodium and sugar and
commence taking into consideration fruits and vegetables which are considerably much
better and easier to obtain. A disregard to the importance of the diet can lead to many
diseases that can be followed in the worst case by death. For example, hypertension,
obesity, diabetes or heart diseases may occur. The most encountered factor which
leads to premature death is the physical and diet inactivity, immediately followed by the
tobacco.
The most common words we use when we talk about food are carbohydrates,
proteins and fats. These are the three subdivisions of the macronutrients which
represent the most valuable fuel for our organism.
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Carbohydrates have one main purpose: supplying energy. They are the easiest
to transform from the complex molecules found in the ingested food into simple
molecules of glucose, which can be afterwards directly oxidized.Carbohydrates are an important source of energy for our central nervous system, aswell as for our muscles and other organs which need an important quantity of energy to
do their job. However, a diet rich in carbohydrates, but poor in proteins and fats, is not
good because sugars are useful only in combination with other substances, such as
water, fats, proteins, minerals etc.
Fats are the ones who store the most energy of all nutritive substances. They are
very important in bodys temperature management system, energy storage, as well asin protecting the internal organs. They also influence the basic metabolism, by starting
chemical reactions that help growth control, reproduction, and the immune function.
Proteins are very important for our body, being involved in almost all body
functions and they are mostly found in the muscular tissue.
Vitamins are organic substances which sustain our organism to grow andfunction normally. For example, the B vitamins can be found in nuts, oatmeal andmilk.
C vitamin is representative for blackberries, cranberries, raspberries or cauliflower. It is
estimated that people need about 60 mg/day. K vitamin prevents internal bleedings and
it can be found in yolk, yoghurt or soybean oil.
Minerals help our organism to synthesize vitamins. For example, the human body
needs calcium from milk, cheese and cauliflower, phosphorus from fish, chicken and
eggs or magnesium from bananas, seeds, almonds or nuts.
The modern man usually needs food not only in order to survive. Recent studies
have shown that feeding can also represent a psychological, need so we need good
quality and different types of food.
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Carbohydrates play the most important role and are taken in the biggest amount
because calories should come from it. Taking low quantities can cause many problems
like cancer or constipation. But on the other hand, if we have a diet high in fiber, we
dramatically reduce our chances of getting a heart disease or obesity. The most
advantageous aspects are the following:
Can be easily converted into energy by the organism
It is used as a source of energy by our cells
They are vital for our brain, muscles and nervous system to work as intended
They aid in the process of eliminating wastes
They are found in the biggest amounts in fruits, milk and yogurt
Proteins also have a very important role for the human body. They can be found
in milk, legumes, nuts, fish etc. and they are involved in a variety of functions. Theyprovide energy when the carbohydrates are exhausted.
As far as fats are concerned, people may affirm that they are controversial. If we
talk about saturated and trans fat we speak about an increase for heart disease, but on
the other hand unsaturated fat