7.0 The first lunar base |
The first lunar base will most probably be entirely
robotic. The reasons are very simple and practical. First,
the costs of maintaining a robotic base will be much lower
than the costs of a manned base. Second, due to the absense
of humans, there will be no loss of life among the
crew. Third, the initial tasks which need to be done at a
lunar base can be easily carried out by robots. Fourth, far
fewer and less complex facilities are necessary to sustain
the robots than would be required to sustain humans.
In order to accomplish any task, only four things are
necessary: resources, power, labor, and planning. Some people
think that money is also necessary, but it is not. Money is
only used to trade for one or more of the other four. On the
moon, we will have free resources! That is, nobody will charge
us for the materials we find there. This is in marked contrast
to the earth, where you must pay someone for every resource
you need except air or seawater (if you are near the ocean).
The moon also has an abundance of free power - solar power. Again,
nobody will charge us for using the solar power we find there.
Our labor at the first lunar base will be androids. Since they
must be operated from the earth they will not be free, but they
will cost roughly the same as earth-bound workers. Most planning
can be done here on earth and thus will not be too expensive.
Indeed hundreds of companies around the world are already making
lots of plans for space, the moon, lunar bases, trips to Mars
and so on. Thus we will be able to reap the results of that
planning at very low cost.
7.1 Site selection Any fool with a map of the moon and a few darts can select
sites for a lunar base. The question is how much more data if any
are needed in order to make a better selection. The site of the first
lunar base must be chosen to satisfy as many needs as possible. The
four primary criteria are: (1) the base must be able to communicate
with the earth at any time, (2) the site must be relatively flat for
safe landing of imports, (3) the site should possess the raw
materials from which we plan to extract our lunar products,
and (4), it should be as close to one of the poles as is practical.
The first criterion limits sites to the near side of the
moon. The second and third criteria constrain the sites to
the maria. And the last suggests a northern mare since there
are few maria in the south and we plan to build an important base
at the north pole of the moon.
It is clear that we must make our site selection from orbital
photos because the Apollo landing data are far too limited a sample
to have any hope of picking an optimal location. Fortunately there
have been quite a few successful lunar photographic missions. The
following list was gleaned from [21, p.25-54], "Solar System Log"
by Andrew Wilson. This list, which is a subset of that given in
[21], shows only the successful US photographic missions
to the moon and does not include the Apollo missions which have
separately accounted for many thousands of pictures of the
moon. Also not listed are numerous Soviet missions which have
also returned large numbers of pictures.
* Spacecraft Launch date Pictures returned ---------- ----------- ----------------- Ranger 7 July 28,1964 4,316 Ranger 8 February 17,1965 7,137 Ranger 9 March 21,1965 5,814 Surveyor 1 May 30,1966 11,350 Lunar Orbiter 1 August 10,1966 211 Lunar Orbiter 2 November 6,1966 208 Lunar Orbiter 3 February 5,1967 182 Surveyor 3 April 17,1967 6,326 Lunar Orbiter 4 May 4,1967 99% of near side Lunar Orbiter 5 February 5,1967 99% of moon Surveyor 5 September 8,1967 19,118 Surveyor 6 November 7,1967 29,952 Surveyor 7 January 7,1968 21,038 . One candidate appears to be the mare Frigoris which spreads roughly over the area from 50 to 60+ degrees north latitude and extends from about 30 degrees east longitude to 30 west longitude. 7.2 Delivering materials to the moon Delivering materials to the moon is a critical cost factor in all lunar financial calculations. Estimates of the cost vary widely. Michael Simon gives a range of $5,000 to $15,000 per kilogram [LB1, p.534] while Lewis and Lewis give $20,000 per kilogram [14, p.207]. Perhaps the best way to estimate the cost is to use Duke's rule of thumb that you need 7 tons in LEO for each ton placed on the moon [LB1, p.66]. One can then simply multiply the LEO cost by 7 to get the lunar soft-landing cost per kilogram. We arrive at: * Table 7.2-1 Cost per kilogram of material soft-landed on the moon Booster LEO cost Lunar cost Proton $ 2,381 $ 16,667 Energia $ 2,727 $ 19,089 Titan 4 $35,133 $245,931 Shuttle $39,898 $279,286 Sources: see section 4.1
.
All of these costs are based upon soft landings made by ordinary
rockets from the earth. Apart from the high cost, this method also
dumps tons of exhaust gases into the lunar atmosphere which tends to
damage the high vacuum which exists there now. It has been estimated
by Richard Vondrak that during each of the Apollo landings the lunar
atmosphere was doubled for a period of two weeks [Nature, vol. 248,
4/19/1974, p.657-9].
There are at least three ways to deliver materials to
the surface of the moon which use little or no propellant! They
are the skyhook, the EMPL, and the direct impact method. Let's
briefly review each of these techniques.
7.2.1 The skyhook The skyhook is extensively discussed in Space Inc, by
Tom Logsdon [37, p.212-222].
The concept of the skyhook can be simply understood as follows.
Nearly everyone has heard of geostationary satellites. They are
those satellites which remain stationary overhead and are used
to beam television programs down to satellite dishes all over
the world - different satellites for different parts of the world
of course. They remain stationary over a single spot on the
earth because their orbital speed happens to match the rotational
speed of the earth below.
Those who are not mathematically inclined can skip this
and the following two paragraphs. The altitude can be calculated
from the following two relationships. First, the square of the
orbital velocity at any radius, "r", is given by:
* G * M / r 7.2.1-1
.
Where G is the universal gravitation constant (6.672e-11) and M
is the mass of the earth (5.976e+24). And second, the orbital
period, one day, is given by the distance traveled which is two
times pi times the radius, divided by the orbital velocity.
* 2 * pi * r / v = one day 7.2.1-2 or
2 * pi * r / one day = v 7.2.1-3
.
You simply square 7.2.1-3 and set it equal to 7.2.1-1 and
solve for "r". This yields "r" = 42,245 kilometers, which is the
distance from the center of the earth. By subtracting the radius
of the earth you get 35,868 kilometers above the surface which is
22,292 miles - the altitude of geostationary satellites.
Well, imagine that you hung a long long
cable down from one of those satellites. The end of the cable
would simply hang stationary over some spot on the ground - and
would extend up into the sky and out of sight. Hence the name
skyhook. Then you could simply attach an elevator to the cable
and climb out into space. Too bad it doesn't work! Apart from the
atmosphere interacting with the cable, the big problem is that
no known material is strong enough to make a cable that long.
But a modified form of the skyhook could be used to place
objects or payloads onto the surface of the moon. This scheme
works because the moon has no atmosphere to obstruct our operations.
First you would establish a satellite in a highly elliptical orbit
around the moon. That means that the satellite would be high
above the moon during parts of its orbit and low over the surface
during other parts of its orbit. Imagine that the satellite
came down to only a few miles above the surface. Then we could
let down our skyhook and pick up or drop off a payload to or from
the surface of the moon. In either case a fast moving "truck" on
the surface would match speed with the moving skyhook before
pickup or dropoff so that there would be no big jerk on the
payload. Of course this scheme is not easy to implement and
preceding explanation has excluded many of the important details.
For more on skyhooks see [14, p.157-9], [23, p.168],
[LB2, p.10, p.12], and/or [SM 16, p.279-81].
7.2.2 The electromagnetic lander The second method is the EMPL. Electromagnetic projectile launchers can and will be built on the moon because they constitute far and away the least expensive way to get material off the moon. But what is not often noticed is that the EMPL could also be used to slow down an object which was flying in from space. Most people these days have heard of Mag-Lev trains. Mag-Lev stands for magnetic levitation because the train is actually lifted off the "tracks" by magnetic fields. The magnetic fields are also used to accelerate and decelerate the train (note the key word "decelerate"). One can then imagine such a train car in an elliptical orbit around the moon. As it swung low over the surface of the moon, it could be maneuvered to touch down on a mag-lev track which would then decelerate the payload to a stop. This landing scheme would not be simple to implement either. But in spite of that, some individuals have worked on the idea - see for example A.B. Binder in [LB2, p.26]. 7.2.3 The lunar slide lander The third method is the direct impact method. As it sounds,
it consists of simply crashing payloads into the surface of the
moon. It is clear that if no retro-rockets are used, the
velocity of any projectile as it approaches the surface of the
moon will be at least lunar escape velocity - which is about
2.4 kilometers per second or 5,370 miles per hour. We can
however determine the impact angle by careful planning and
the expenditure of a relatively small amount of propellant. Our
payload can be maneuvered into a highly elliptical orbit such
that at its low point (called the periselenium) it is nearly
tangent to the surface of the moon, in other words horizontal.
Finally, when the payload is about to pass over the runway in the
proper direction, we would use a small thruster on board the payload
to drop it onto the runway where it would slide to a halt. One such
lunar slide lander was described by K.A. Ehricke in [LB1, p.848-853].
Another lunar crashlander was described by E.F. Marwick in [LB2,
p.168].
The lunar slide lander is by far the easiest (and cheapest)
to construct with regard to lunar facilities, requiring only a
long flat runway. It will require very little propellant to be
discharged into the lunar environment. Its construction will involve
selecting an appropriate site which is flat and level and relatively
free from large boulders. The whole area will then be cleared of
rocks just as the farmers used to do. This will produce a field
covered with regolith. Depending upon the depth of the regolith
it may be necessary to cover it with additional regolith to
increase its depth.
Imagine that you were standing at the site of the LSL to
watch the landing of a payload. Up in the blackness you would
see nothing but millions of stars in a black sky. The earth and
perhaps the sun too would be about 30 degrees above the horizon.
The payload would be invisible somewhere up among the stars
and still many miles away. Finally way off in the distance,
coming from the south and close to the horizon you would see the
firey plume of the onboard thruster firing upward to push the
payload down. In seconds the payload would hit the LSL. There
would be a spray of regolith but no sound as the payload embedded
itself deeply in the soil. An android, sitting in his MPV,
would drive out to the pit where the payload was stuck.
He would begin digging to recover the payload and load it
aboard the MPV.
It may be possible to combine the skyhook and the lunar slide
lander to yield a system which uses no propellant at all. To do
this it would be necessary to have a spacecraft orbitting the
moon with which payloads coming from earth would rendezvous. This
spacecraft would then be responsible for landing the payloads. The
obvious penalty would be the cost of the lunar orbitting platfrom
equipped with the skyhook - few things in life are free.
7.3 Lunar products The moon has no life of any kind - no plants and no animals.
It is simply a large body of rock and dust. But it is also loaded
with treasure. It contains nearly all the known elements and they
are often found in higher purity than they are found here on
earth. Unfortunately, it has little of three of the elements most
important to life on earth - namely, hydrogen, nitrogen, and carbon.
But, as we shall see, "little" is a relative term.
Since we plan to commence mining operations in one of the
maria, let us look at the components of the soil there. The
following table is based on Apollo mare soil samples as given
in [LB1, p.382].
* Table 7.3-1
Element Symbol Percent(by wt)
Oxygen O 42.26
Silicon Si 19.68
Iron Fe 11.92
Calcium Ca 8.53
Aluminum Al 7.20
Magnesium Mg 4.68
Titanium Ti 4.65
Sodium Na 0.35
Manganese Mn 0.15
Chromium Cr 0.10
Total 99.52
.
Also let us look at the concentrations of some other
interesting elements in the lunar soils.
* Table 7.3-2
Element Symbol ug/gram source
Sulfur S *1000 [4, p.159]
Chromium Cr 700-3600 [LB1, p.598]
Barium Ba 85-767 [LB1, p.598]
Nickel Ni 131-345 [LB1, p.598]
Strontium Sr 104-234 [LB1, p.598]
Hydrogen H 10-211 [LB1, p.572,584]
Carbon C *115 [4, p.159]
Potassium K *83 [18, p.133]
Nitrogen N *50-100 [4, p.159]
Florine F 37-278 [LB1, p.598]
Helium He 30 [2, p.169]
Zinc Zn 6-49 [LB1, p.598]
Copper Cu 6-31 [LB1, p.598]
Thorium Th 1-13 [LB1, p.96]
Uranium U 0-3 [LB1, p.598]
* - ppm (parts per million, assumed by weight)
.
Now it is time to consider what products are worthwhile
extracting from the lunar regolith.
Four products are of immediate interest:
* 1. Silicon for solar power arrays
2. Aluminum for solar power arrays
(and possibly for use as a propellant)
3. Helium-3 to be used in fusion reactors on earth
4. Oxygen for use as a propellant
.
7.3.1 Solar power arrays
The most accessable form of power available on the moon
is solar power. Everything we want to do requires power. Power
is like money in that you can't have too much of it. Williams
et al [51, p.275] have estimated that the equipment necessary
to mine enough regolith to produce one ton of helium-3 per week
would weigh nearly 1000 tons and require about 3 Mw of power
to run it. Assuming no operation during the lunar night, this
facility could mine enough helium-3 each year to satify the
total electricity demand of the US. The incident solar radiation
at the surface of the moon is about 1400w per square meter where
the surface is perpendicular to the sun's light. This is higher
than most places on earth because the moon has no atmosphere to
decrease the transmission of the light. Assuming a 10% solar
cell efficiency, it would take about 21,500 square meters to
produce 3Mw. This would be a square about 150 meters on a side.
Even at only 1 kilogram per square meter this would be about 25
MT (including some extra for packaging). Bringing that much weight
from earth would be very expensive. We wish to avoid that cost by
bringing a manufacturing facility instead. This will allow us
to build on site an unlimited quantity of solar cells which
of course corresponds to an unlimited power supply - instead
of the limited amount of 3Mw (or any amount). Texas Instruments has
developed a new "low technology" process for producing solar cells
which they claim will cut solar cell costs in half [52, p.76]. The
cost is not of concern here; rather, the fact that these solar
cells can be produced without complex "high technology" processes.
The TI process requires low grade silicon and aluminum foil [52,
p.76]. Fortunately the moon has plenty of both. You can see from
table 7.3-1 that about 20% of the lunar surface is silicon and
another 7% is aluminum.
Given these huge quantities of aluminum and silicon,
we should be able to dump regolith into a machine and have
silicon and aluminum pop out the other side. In short, we will need
silicon and aluminum producing machines and the TI solar cell
machine. With these three machines, we can build a solar array of
any size we want - 3Mw or 3000Mw.
7.3.2 Helium-3! Why helium-3? The short answer is that all the electricity used
in the United States in 1987 could have been generated from 28 tons
of helium-3 [10, p.4]. Based upon its utilization for the
production of electricity on earth, its value has been
estimated at $1,000,000,000 per ton [10, p.4]. The problem
is we don't have much helium-3 here on earth.
Nuclear fusion is the process of combining light atomic
particles to produce heavier atomic particles. This is how
our sun produces its power. Hydrogen is "fused" to produce the
element called helium. Hydrogen occurs in three forms called
isotopes: hydrogen (1 proton), deuterium (1 proton, 1 neutron),
and tritium (1 proton, 2 neutrons). All three isotopes are
available here on earth. Deuterium oxide (heavy water) is present in
water at about one part in 5000 [110, p.28] and can be relatively
easily concentrated to nearly 100% by electrolysis.
Tritium is radioactive with a short half-life (12.3 yr) and thus
is not found in nature. However, it is produced in heavy water
fission reactors when a deuterium atom captures a neutron
from a fissioning uranium atom. And it can also be produced by
fissioning a lithium-6 atom with a neutron in a bomb [8]
or in a liquid lithium reactor. Unfortunately lithium-6
constitutes only about 6% of all lithium, but lithium-6 is a
lot easier to separate from lithium-7 than U-235 from U-238.
Most fusion work has involved the D-T (deuterium,tritium)
reaction because it is the easiest reaction to start - i.e.
the one requiring the lowest ignition temperature [2, p.172].
However, that reaction produces large amounts of energetic
neutrons [7] which require large amounts of shielding and are
difficult to convert into electricity. The next easiest
reaction to start is D-D, but this reaction produces only
a tiny fraction of the power of the D-T reaction [7].
Nuclear fusion can also occur with helium-3 although
its ignition temperature is much higher [2] - that being one
of the drawbacks of helium-3. The deuterium - helium-3
reaction "is of major interest because the fuel and the
main reaction products are charged particles, which are
not radioactive" [2, p.167]. This means two things: first,
that the world need not fear another Chernobyl because this
fusion reaction is environmentally safe, and second, that
electric power can be produced directly from the charged
particles produced by the reaction. That means a higher
plant efficiency. A tandem mirror reactor design proposed
by J.F. Santarius [9] offers the possibility of a 70% overall
plant efficiency [2, p.173].
The two major components of the universe are hydrogen
and helium. The proportions of these components are estimated
to be 93.4% hydrogen and 6.5% helium [2, p.167]. Helium itself
occurs in two forms: helium-3 and helium-4. The former
contains two protons and one neutron for an atomic weight
of 3 and, hence, is called helium-3. The latter contains two
protons and two neutrons for an atomic weight of 4 and, hence, is
called helium-4, or just helium. Unfortunately, helium-3 is much
rarer than helium-4 and very little helium-3 is available on earth.
In the primordial universe there were only about
140 helium-3 atoms per million helium-4 atoms [1]. Our sun is about
92.1% hydrogen and 7.8% helium [3] thus indicating how much hydrogen
has been burned into helium. Hot gases are constantly given off by
the sun and they radiate out into space in all directions. This is
called the solar wind and it contains roughly the same components as
the solar corona [4] which include hydrogen, helium, oxygen, carbon,
nitrogen, and other elements and compounds in trace amounts [3]. The
ratio of helium-3 to helium-4 in the solar wind is about
480 ppm (parts per million) [5]. The lunar regolith has been
absorbing part of the solar wind for billions of years. Analysis of
samples from the Apollo landings has shown that the concentation of
helium-4 in the regolith is about 30 ppm and that the ratio
of helium-3 in the samples is about 400 ppm of helium-4 [6].
A detailed estimate given in [2, p.170] shows that the lunar
maria contain over 600,000 tons of helium-3 and a further
500,000 tons in the highlands for a total estimate of
1,100,000 tons for the lunar surface [2, p.170].
Based upon its utilization for the production of electricity
on earth, its value has been estimated at $1,000,000,000 per ton
[10, p.4].
7.3.3 Lunar oxygen Quite a large number of papers have been written which discuss recovering oxygen from the moon for shipment down to low earth orbit. A short list follows: * 1. [LB1, p.531-542] "A Parametric Analysis of Lunar Oxygen
Production", M.C. Simon.
2. [LB1, p.543-550] "Lunar Oxygen Production from Ilmenite",
M.A. Gibson, C.W. Knudsen.
3. [LB1, P.551-558] "Oxygen Extraction from Lunar Materials:
An Experimental Test of an Ilmenite Reduction Process",
R.J. Williams.
4. [LB1, p.559-570] "A Carbothermal Scheme for Lunar Oxygen
Production", A.H. Cutler, P. Krag.
5. [LB2, p.22] "Delivering Liquid Oxygen to Low Earth Orbit",
Bilby, McGlamery, Ashley.
6. [LB2, p.34] "Oxidation and Reduction of Ilmenite; Application
to Oxygen Production on the Lunar Surface", R.A. Briggs,
A. Sacco Jr.
7. [LB2, p.43] "Lunar Mining of Oxygen Using Fluorine",
D.M. Burt.
8. [LB2, p.52] "Conceptual Design of a Lunar Oxygen Pilot
Plant", Christiansen, Simonds, Fairchild.
9. [LB2, p.156] "Parameters for Electrolysis of Molten
Lunar Rocks and Soils to Produce Oxygen and Iron", Lewis,
Haskin, Lindstrom.
10. [SM 22, p.123-131] "Lunar Oxygen Production by Vapor
Phase Pyrolysis", W.H. Steurer.
11. [SM 20, p.360] "Silicon, Aluminum, and Oxygen from
Lunar Ore", R. Keller.
12. [SM 25, p.69-77] "Magma Partial Oxidation: A New Method
for Oxygen Recovery from Lunar Soil", R.D. Waldron.
13. [SM 43, p.331-341] "Lunar Oxygen Production by Pyrolysis of
Regolith", C.L. Senior.
14. [SM 44, p.342-345] "Lunar Production of Oxygen by Electrolysis",
R. Keller.
15. [SM 45, p.346-351] "Design of an Automated Process Control System
for Lunar Oxygen Production", B.D. Runge & T. Stokke.
.
We do NOT recommend shipping of lunar oxygen to LEO for several good reasons. They are: 1. It appears that fuel lifted from earth will be significantly
cheaper than fuel from the moon - at least for a very long time.
This assertion is based upon the apparently very low cost of payloads
lifted via conventional powder guns or hydrogen gas guns. See
section 4.2.
2. The establishment of such an operation would take several
years and would cost billions of dollars if it were established in
the manner suggested by most of the above authors.
3. If the oxygen were lifted off the moon by rocket, that would
damage the precious vacuum there and if the oxygen were lifted off
the moon via an EMPL, one would have to wait years for the
establishment of that facility. There is also the question of where
the rocket engines come from if rockets are used.
4. The propellant selection is also questionable. The highest
specific impulse would be that of LOX and LH2.
But since there is very little hydrogen on the moon, the
necessary hydrogen would still have to be lifted from earth. This
amounts to 14.3% of the mass rather than 11.1% because LOX and LH2
are normally burned in the ratio of 6 to 1 rather than 9 to 1.
5. If another propellant is selected, such as aluminum, which
could be manufactured on the moon, then one must consider the cost
of establishing that manufacturing facility.
7.4 The first small EMPL We need a small EMPL at the site of the first lunar base
to get our valuable products off the moon. The EMPL is by far the
best way to get material off the moon. It requires only
electricity and it doesn't produce any exhaust gases. The
amount of electricity required can be calculated easily from
the mass of the moon and its radius [42, p.343]. That number
works out to 0.784 kilowatt-hours per kilogram. The corresponding
number for the earth is 17.36 kilowatt-hours per kilogram. Many
articles have been written about lunar EMPLs, especially by
T.A. Heppenheimer [43, p.301-309], [44, p.176-183], [45, p.242-9],
[46, p.305-12], [LB1, p.155-167]. Also see [SW 5, p.157],
[LB2, p.21], [LB2, p.68].
How much power is required by the EMPL? Well, that too is
easy to estimate. The kinetic energy of an object is given by
one half of the product of the mass times the square of its
velocity. Assuming a one kilogram mass and a velocity of three
kilometers per second gives a kinetic energy of 4.5MJ (megajoules).
If in addition, we launch the object in 1/2 second, then the power
required is 4.5MJ per 1/2 second or 9Mw (megawatts). That is,
9Mw per kilogram of mass to be launched. Notice that this is
continuous power. The power demands can be reduced by any
amount by using capacitors to drive the EMPL - but that means
we need the capacitors. Using capacitors, we can launch 1 metric
ton projectiles roughly every 1000 seconds or 16.67 minutes with a
9Mw solar power array.
How big will the EMPL be? Using the basic equations of
distance, velocity, and acceleration and the two known parameters
given above (3 kilometers per second velocity and 1/2 second
launch time) we can easily calculate that the length of the
EMPL will be 750 meters. The acceleration will be about 600 gees
or 600 times earth's pull of gravity. Of course, these parameters
can be changed if others appear more suitable. It is merely
750 copies of a 1 meter unit all lined up in a row or 375 copies
of a two meter unit. One must keep in mind that the power
required to drive the EMPL varies inversely with the length of
the EMPL. That means that an EMPL one half the length needs
twice the power and so on.
Where should we place the EMPL? If we were on the "top" of the
moon, we could launch projectiles horizontally to hit the earth.
If we were on the moon's equator, we would have to point the EMPL
straight up to hit the earth. Thus it is clear that the proper
launch angle is approximately:
* Launch angle = 90 - latitude of launch site
.
Therefore, if the site of our first lunar base is at 60 degrees
north latitude, then we would want to launch at 30 degrees from the
surface. So we would look for a convenient crater whose northern
rim has a slope of about 30 degrees. That is where we would build
the first small EMPL.
7.5 Lunar hydroponic facility Why do we need a lunar hydroponic facility? Of course
there are multiple reasons. The first and most obvious is
simply to support human visitors. Is clear that people need
food and it is far too costly to import food from the earth.
Second, we need to make sure that we can successfully grow
food in the harsh environment of the moon before we send
people there. And third, it will verify that we can build
a significant facility by remote control from the earth.
What are the problems we must overcome? The biggest
problem is the lunar night. When the sun goes down, the
temperature will fall from 120 degress Centigrade to -150
degrees Centigrade [LB1, p.388]. However, at a depth of only
150 centimeters below the surface, the temperature is estimated to
be nearly constant at about -20 degrees Centigrade [LB1, p.617].
This is about the average of the day and night temperatures.
Thus if we were to bury the facility, it would only be necessary
to elevate its temperature by about 45 degrees Centigrade. In
addition, an underground facility would be protected from solar
and cosmic radiation although radiation protection is less
important for plants than for people. It would also protect
the facility from punctures by micrometeors to which a surface
facility would be vulnerable. Of course a burried facility
is more difficult to illuminate but a system
of mirrors and fiber optic cables will solve that problem. If
such a system were employed, it would be "low tech", it would
be less dangerous than electric lighting, it would have very
low maintenance, and it could be lit with light from anywhere
on the surface of the moon.
The simplest way to overcome the problem of the sun going
down is to have solar arrays in several different parts of the
moon so that at least one will always be in sunlight. Of course
a polar array will always be in the sunlight if it is tall
enough or if its geometry is specially designed.
7.6 What has to be taken to the moon? The most significant decision regarding what we first send
to the moon will be whether or not we plan to have humans on the
moon early in the program. The answer is no! They are not needed
and are not cost effective.
The following equipment seem to be required:
* 1. Nuclear power source
2. Aluminum extraction machine
3. Silicon extraction machine
4. Solar cell machine
5. Androids
6. Multi-purpose vehicles (MPV)
7. Volatile extraction machine
8. "Mond" process equipment
9. Vapor deposition machine and molds
10. Mold maker machine
11. Landing guidance system
12. Communication equipment
13. Miscellaneous critical components
.
In the following sections each of these components will
be reviewed briefly.
7.6.1 Nuclear power source There are really only three ways to provide power to
the first lunar base: (1) solar power (photovoltaic)
arrays on site, (2) beamed power from earth, and (3) a nuclear
power source on site. Other options such as batteries or
gasoline powered generators simply won't last long enough. The
moon has no winds, tides, waves, or "selenothermal" power to be
harnessed either.
Solar power (photovoltaic) arrays are a good power source.
They last for many years. But they have some problems of their own.
First, the current photovoltaic technology will provide only
about 21 watts per kilogram of solar cells [61, p.69]. That
means 21 kw per metric ton or 4.76 metric tons per 100kw. That
in itself is not too bad, but remember that the solar cells
will receive only limited illumination during the lunar night. That
light is "earthlight" as opposed to sunlight or moonlight.
Although earthlight is perhaps 100 times as great as moonlight,
it is tiny compared to sunlight. It has been suggested
by Dani Eder [SM 11, p.301] that sunlight be used during the
day to heat the regolith until it glows (using mirrors of
course) and then direct that glow onto the solar cells during
the lunar night. This seems marginal considering the mass of
the mirrors and their supporting structures that must be
brought from earth and deployed. One also wonders how fast the
exposed surface would cool (and therefore stop glowing) when the
ambient temperature drops to -150C - but it needs to be
investigated further.
Beamed power from earth could provide the answer, but it
would require an array of receivers to be emplaced on the
moon. If these are simply solar cells, then all we would need
would be some powerful lasers on the earth focusing their
beams on the arrays on the moon. Clearly this beamed power
would only be required during the lunar night. Of course we
assume that the arrays would still function with reasonable
efficiency even though the wavelength of light of the laser
beam would obviously be far different than the full spectrum
received from the sun. It would require several multi-megawatt
lasers here on earth, perhaps located in desert areas 120 degrees
apart around the world. The array on the moon would be
circular and closely packed so that a significant portion of
the spread beam could be intercepted and recovered there.
Nuclear power, on the other hand, will work day and night for
many years. Remember the KISS principle (Keep It Simple Stupid).
Since there won't be any people at the initial base we won't need
any heavy shielding for our reactor. Thus we can have either
more power continously or more power for a longer period.
The US government has invested millions of dollars in the
development of a small nuclear power plant for use in space.
This program (SP-100) is quite mature and the financial investment
has already been made. J.R. French has written an interesting
paper called "Nuclear Powerplants for Lunar Bases" which
discusses the SP-100 reactor in detail [LB1, p.99-106]. This
article mentions that the mass of the reactor is less than
3 metric tons and that it will produce 100kw for at least 7
years. If we purchased one or two of those reactors, it would
power our project and would also help amortize their development
costs. The interested reader might also review "Nuclear Energy -
Key to Lunar Development", by Buden and Angelo [LB1, p.85-95].
7.6.2 The aluminum extraction machine It was mentioned in section 7.3 that aluminum constitutes
roughly 7% of the maria regolith. Therefore, one should be able to
simply feed in regolith and produce aluminum foil (by vapor
deposition), other aluminum items and aluminum-depleted
regolith as products. This machine will operate on electricity
supplied by the nuclear reactor. Any heat that is required will
be supplied by the sun via mirrors. The foil product will be
fed to the solar cell manufacturing machine. By the way, this
foil should be very shiny since there will be no oxygen in the
atmosphere to oxidize it and destroy the shine - so it could
be used for mirrors as well.
Eventually wire will be needed to build electromagnets for
the EMPL. It is well known that aluminum is used for power
transmission lines but it is not as good a conductor as silver
or copper. Silver is very rare in lunar soils and even copper
is only present in small quantities (see table 7.3-2).
7.6.3 The silicon extraction machine The maria regolith is nearly 20% silicon. Thus we can build a machine which will produce silicon from regolith. This silicon need not be high grade for the "low technology" solar cell production process being developed by Texas Instruments [52, p.1,76]. The silicon extraction machine will also operate on electricity from the nuclear reactor. Again, any heat that is required will be provided by a solar furnace. The silicon product will be fed to the solar cell manufacturing machine. 7.6.4 The solar cell machine Hopefully this machine will be built for us by Texas
Instruments. Eric Graf, marketing manager of TI's photovoltaic
program, told me that they would be too busy to take on other
projects until the end of 1994, but perhaps then they could be
enlisted in our project. The proposed machine would simply
accept the aluminum and silicon produced by the preceding two
machines and would produce solar cells as its product. Of course
we expect that other inputs will be required as well, but we
will simply have to wait until that information becomes available.
The TI process produces 4 inch square cells which are assembled
into 12 x 4 inch strips. It will be the responsibility of the
androids to collect the strips from the solar cell machine and to
assemble them into working arrays.
7.6.5 Androids The robots which will operate the first lunar base will be
androids. They will do all of the "manual" labor at the base. These
androids will be remotely controlled from the earth - a truly exciting
computer game! We will need as many as six to ten crews on earth
to operate the androids 24 hours a day. There will be plenty to do
even during the lunar "night" since there will still be enough light
to see clearly and therefore to accomplish useful work. The nuclear
power source will provide electricity to keep most operations going.
We will need at least three earth stations from which to control
the lunar operations. They could be located 120 degrees apart on the
earth. For example: at 110 - 120 W in the US or Mexico, at 0 - 10 E
in north Africa or Europe, and at 120 - 130 E in Australia or Japan.
Initially the androids will unpack all the equipment from the
lander. After selecting a suitable nearby site, they will assemble
the machines, connect up the electric power from the reactor to each
of the machines, run all diagnostic checks and activate them. They
will keep the volatile extraction machine supplied with fresh regolith
using the MPVs. When solar cell production begins, they will have
the additional responsibility of assembling and connecting the cells
into arrays.
When the lunar slide lunar becomes operational, they will also
have to retrieve the payloads landed each day.
7.6.6 Multi-purpose vehicles (MPV) There is a clear need for vehicles to carry heavy loads
during the construction of the first lunar base. They must be
light but strong and they must be able to tolerate the wide
temperature swings which they will face on the moon.
These vehicles will be designed to be operated by humans,
but will actually be operated by the androids. Here on earth
the operator will wear a headset which will allow him to see
what the android sees. He can then tell the android what to do.
The vehicles will need a scoop similar to that of a front
loader. This scoop will be used to feed regolith into the
various machines which will process it. It would also be helpful
if they had a blade which could be used for grading the site of the
lunar slide lander and a rake to help remove the rocks from the
site. Perhaps other devices would also be useful such as a crane,
a winch, a jack-hammer, an auger, a backhoe, etc.
7.6.7 Volatile extraction machine The volatiles will be the first products to be extracted from the regolith. Oxygen is the only (potential) volatile which constitutes more than a fraction of a percent of the moon. It amounts to about 42% of the lunar maria surface. Oxygen of course has many uses, but we are really interested in the gases (and carbon) which are present in low concentrations. * Element Symbol ug/gram source
Hydrogen H 10-211 [LB1, p.572,584]
Carbon C *115 [4, p.159]
Nitrogen N *50-100 [4, p.159]
Florine F 37-278 [LB1, p.598]
Helium He 30 [2, p.169]
* - ppm (parts per million, assumed by weight)
.
This machine will simply heat the regolith (using
concentrating mirrors rather than electricity) and collect
whatever gases boil off. According to the above list we could
expect 10-211 grams of hydrogen per metric ton of regolith,
about 115 grams of carbon and so on. We will probably get a
lot of oxygen too - far more than the other gases put together.
The machine will separate the gases so that they may be put to
good use. We will need a special tank to hold the helium
because as anyone who has taken high school chemistry knows,
helium will seep through any container and escape. At a billion
dollars a metric ton, helium-3 is worth over $28,000 per ounce
or about 70 times as valuable as gold. Thus we want a multi-
walled tank which constantly pumps out the outer layers and
puts the helium back into the inner layers.
Hydrogen may be converted to water to make storage less
dangerous. It could also be combined with florine to make
hydrofluoric acid which could then be used to recover materials
from the regolith using the process described in R.D. Waldron's
paper, "Total Separation and Refinement of Lunar Soil by the
HF Acid Leach Process", [SM 23, p.132-49].
The carbon will be combined with oxygen to give
carbon monoxide. Initially we will need as much carbon monoxide
as possible to make up for losses in the Mond process. Later
the carbon and/or carbon monoxide can be converted to carbon
dioxide to be used to grow food for humans.
7.6.8 "Mond" process equipment Over a century ago Ludwig Mond invented the gaseous carbonyl
process. This is a very simple process wherein various metals
in the feed material are dissolved by carbon monoxide at a
pressure of 10 to 100 atmospheres and a temperature of 100 to
200 degrees Centigrade. The product is a clear liquid which
contains the dissolved metals in the form of carbonyls or
compounds of the metals and carbon monoxide. Lewis and Lewis
give an excellent account of this technique in "Space Resources:
Breaking the Bonds of Earth" [14, p.203-205,260-265]. Many
metals form gaseous carbonyls including: iron, nickel, cobalt,
osmium, iridium, ruthenium, rhodium, tungsten, chromium, and
others [14, p.261]. It is important to notice that aluminum,
magnesium, and titanium are missing from this list. (See table
7.3-1). This means that those three metals will be left in
the residue once the Mond process is done.
The liquid carbonyls can be fractionally distilled to separate
out each of the metals. This is a simple process and can easily
extract the iron carbonyl. The remaining carbonyls can be
stored in tanks for further processing at some later date.
The amount of non-iron carbonyls should not be
more than a few percent of the amount of iron carbonyl.
7.6.9 Vapor deposition machine Chemical vapor deposition is a very interesting process
whereby a solid object can be built up by depositing layer upon
layer of metal from a metal vapor onto the surface of a mold.
Lewis and Lewis give a nice description of this technique [14,
p.262-4]. In our case we would use the iron carbonyl provided
by the Mond process machine described in the preceding section.
Using molds brought from earth or made locally (see next
section), high purity iron parts could be built up by the
chemical vapor deposition (CVD) technique.
The regolith is about 12% iron by weight. That is a huge
amount of iron. For every 30 grams of helium we will get
about 119 kilograms of iron. For every 1 gram of helium-3
(1 part in 2500 of helium), we will get about 9917 kilograms
or 9.917 MT of iron. For every kilogram of helium-3 we will
get 9,917 MT of iron. For every metric ton of helium-3 we will
get 9,917,000 MT of iron. The conclusion is that we can build
all of our structures out of iron and still have so much left
over that we won't know what to do with it. Perhaps we can
build Isaac Asimov's "Caves of Steel" - cities covered by domes
made of steel.
During the deposition of the iron onto the molds, large
amounts of carbon monoxide will be liberated. This gas will
be collected and recycled back to the Mond process machine.
It will require about 300 kilograms of carbon monoxide
(which is about 129 kg of carbon and 171 kg of oxygen)
to dissolve the expected 119 kilograms of iron in each ton of
regolith, but each ton of regolith will only give us about
0.25 kilograms of new carbon monoxide. Remember that we will
also get a few kilograms (3-5 perhaps) of other carbonyls.
This means that we will have a net loss of carbon (which will
be tied up in non-iron carbonyls). Of course this can be
solved by depositing out those other metals to free up
the carbon monoxide. Another possibility is to import carbon
from the earth. This would simply be payloads of graphite
which would land on the lunar slide lander.
7.6.10 Mold maker machine It is clear that we can send only a limited number of
molds to the moon on the first landing, so there will be
many parts that will have no molds. The mold maker will be
computer controlled and will be capable of making molds to
reproduce any moderate sized part. Since a large object can
be made out of a number of smaller parts, this should allow us
to make anything. Mold patterns will be transmitted from earth.
A completed set of molds will be turned over to the
gas deposition machine for fabrication of the actual part(s).
Replacement parts can be produced and the new parts can be
installed by the androids - even on each other.
7.6.11 Landing guidance system The lunar slide lander will need some on site equipment
to help guide the payloads to (relatively) safe landings.
Due to the slow rate of rotation of the moon, a satellite in polar
orbit around the moon will pass over a given spot only about
once every 27 days. That means that we will have only one
chance every 27 days to land each payload. Conversely, if
payloads are sent up from earth once a day, we will eventually
have once chance per day to land a payload.
From the rotational period of the moon and the radius of the
moon we calculate that the equatorial rotational velocity is about
2.313 meters per second or 8.327 km/hr. The rotational velocity
decreases to zero at the poles. The velocity at any latitude is
the equatorial velocity times the cosine of the latitude. Thus
at 55 degrees north, the rotational velocity will be 4.776 km/hr.
This means that if a satellite is in a two hour polar orbit, it will
pass 9.552 km further west on each orbit. Payloads will be in
polar orbits because any satellite in polar orbit will eventually
pass over the entire surface of the planet below and therefore
could land anywhere it chose. A satellite in an inclined orbit
will never pass over any area of higher latitude than the
inclination of its orbit. In the case of earth, that means
that the space shuttle whose orbit is inclined 28.6 degrees,
will never pass over any area north of 28.6 degrees north
latitude or south of 28.6 degrees south latitude.
It seems likely that there will be many payloads orbiting
the moon just waiting for the moment when they will pass over
the lunar slide lander so that they can land. The landing
guidance system must keep track of all payloads in orbit and
their positions. It must calculate which payload will be the
next to land and precisely when the on board thrusters must
be fired to adjust the orbit and bring the payload down on the
slide lander. The components of this landing system must be
deployed, checked out, and activated by the androids.
7.6.12 Communication equipment The lunar base will be operated remotely from the earth. This implies several communication and control sites located at widely separated locations around the world so as to be able to monitor operations 24 hours a day. The androids will be sending two video channels and one audio channel each and other cameras placed around the lunar base will also be sending video channels. The earth stations on the other hand will communicate mostly over low bandwidth channels. All this implies significant communication requirements and hence equipment. This equipment is needed on site from startup and therefore must be delivered on the first landing. 7.6.13 Miscellaneous critical components There will be many components which we cannot build at
the lunar base due to lack of resources or manufacturing
facilities. In addition, there may be component failures
which result in equipment not working - including the androids.
We must anticipate which parts are most likely to fail and
provide spares which can be installed by the androids. TV
cameras and computer chips seem like good examples.
We plan to build several major facilities at the lunar
base including the EMPL, the hydroponics facility, the crew's
quarters, and a railroad. The "brains" of each of these
facilities probably should be sent on the first trip due to
their fragility. The lunar slide lander will be a very rough
landing and fragile payloads will be difficult to land safely.
7.6.14 Summary of initial regolith processing There will be five machines which will sequentially process the regolith to produce as their primary product - solar cells. They are: (1) the volatile extraction machine, (2) the "Mond" process machine, (3) the aluminum extractor, (4) the silicon extractor, and (5) the solar cell machine. Along the way numerous other products will be produced. The vapor deposition machine which fabricates parts and the mold maker can be deployed separately. The following list indicates the inputs and products of each of the machines. (1) Volatile extraction machine
inputs products destination
-------- ---------- ---------------
regolith oxygen tanks
hydrogen water, tanks
nitrogen tanks
florine tanks
helium tanks
carbon monoxide "Mond" process(2)
other gases tanks
residue(1) "Mond" process(2)
(2) "Mond" process machine
inputs products destination
-------- ---------- ---------------
residue(1) iron carbonyl vapor deposition
carbon monoxide(1) other carbonyls tanks
residue(2) aluminum machine(3)
(3) Aluminum extraction machine
inputs products destination
-------- ---------- ---------------
residue(2) oxygen tanks
aluminum solar cell machine(5)
residue(3) silicon machine(4)
(4) Silicon extraction machine
inputs products destination
-------- ---------- ---------------
residue(3) oxygen tanks
silicon solar cell machine(5)
residue(4) titanium recovery
(5) Solar cell machine
inputs products destination
-------- ---------- ---------------
Aluminum(3) solar cells power array
Silicon(4)
7.7 Summary of initial lunar base development The initial purpose of the first lunar base is to establish
the nucleus of a bootstrapping operation which will
eventually lead to the establishment of numerous manned bases
at many different sites all over the moon.
In order to minimize costs there will be one and only one
soft landing on the moon. Also in order to minimize costs,
no humans will be sent to the moon for several years during
which time the facilities necessary to maintain humans will
be constructed from local materials.
The initial tasks to be performed are:
* 1. Set up and activate initial base components
2. Begin assembly of large solar power arrays
3. Prepare the lunar slide lander
4. Receive payloads from earth and assemble them
5. Expand the labor force
6. Expand the production facilities
7. Begin producing lunar products - iron and helium-3
.
7.8 Costs of lunar projects The cost of space projects is often difficult to determine.
The Soviet Union has conducted a long series of lunar missions
including two Lunokhod rovers, at least three sample-return missions,
and numerous photographic missions. Lunokhod 1 traversed more than
10 kilometers of the moon and returned over 20,000 TV pictures.
Lunokhod 2 traversed more than 37 kilometers of the moon and returned
over 80,000 TV pictures [31, p.142]. Lunokhod 1 traveled at 0.1 km/hr
and Lunokhod 2 traveled at 0.2 km/hr [14, p.183]. Sadly we have no
cost figures for any Soviet missions - so they have been left out.
Similarly, we have no cost data on the recent (January 1991)
Japanese lunar mission or their future lunar or Martian missions.
So they have been omitted also.
7.8.1 Past unmanned US lunar projects For the reader who may be looking for detailed information on various space missions, we recommend the "Solar System Log" by Andrew Wilson, published by Jane's, London, 1987 [Ref 21]. This book provides copious data and many pictures and diagrams of most extraterrestrial exploratory space missions up to the date of its publication. The only significant omission is the US Apollo program. Data given in the following four paragraphs are excerpted from Wilson's book. 7.8.1.1 Ranger series The US built 9 Ranger spacecraft in the early 1960s to support the Apollo program. They were intended to obtain closeup images to the moon's surface by the simple means of crashing into the moon. The spacecraft would simply transmit TV images as they came down. Of the nine rangers, three were successful, Rangers 7,8, and 9. Together they returned over 16,000 pictures of the moon. The program cost about $267 million in 1965 dollars [21, p.30]. That scales up to $1.105 billion in 1990 dollars. 7.8.1.2 Lunar Orbiters The Boeing Company built five lunar orbiters for $80 million as part of a $200 million program [21, p.38]. These orbiters were spectacularly successful. All five orbited the moon and returned pictures. Together they photographed 99% of the moon. All of the orbiters were deliberately crashed into the moon when they ran out of film so that they wouldn't interfere with later issions. The cost of the program in 1990 dollars would be about $828 million. 7.8.1.3 Surveyor series The US built seven Surveyor spacecraft in the 1960s which were intended to support the Apollo program. They were supposed to soft-land and survey the planned Apollo landing sites. Of the seven, five successfully landed on the moon and returned pictures (see table 7.1-1). The series had severe development problems and cost about $469 million in current dollars ($2 Billion in 1984 dollars) which was far more than the original estimate of $50 million [21, p.36]. 7.8.1.4 Summary of unmanned US lunar programs * Spacecraft Cost (yr) Cost (1990$) Ranger series (9) $267 M (1965) $ 1.105 B Lunar orbiters (5) $200 M (1965) $ 0.828 B Surveyors (7) $469 M (1965) $ 2.514 B . 7.8.2 The Apollo (manned) program Originally there were ten moon landings scheduled, but the
number was cut to seven because of escalating costs [15, p.5].
The Apollo 13 mission suffered an explosion about 90% of the way
to the moon causing the mission to be aborted. The crew was lucky
to return alive. The other six mission were successful, landing
twelve men on the moon and returning 382 kilograms of soil and
rocks. The first landing, by Apollo 11, was at 16:17:43 EDT on
July 20,1969. Four hours later Neil Armstrong became the first
human to set foot on the moon. Apollos 15,16, and 17 carried
rovers which weighed about 209 kilograms each [23, p.96]. The rovers
greatly extended the range of those missions, but were left on the
moon.
The Apollo moon landings were a "stunt" - a very expensive
stunt. The US cannot afford another super-expensive stunt such
as a joy-ride to Mars for three to six astronauts. Future projects
must be profitable - and they can be.
7.8.2.1 Apollo 11 * The Apollo 11 mission Datum Source
Launch July 16,1969 [41, p.73]
Landing July 20,1969 "
Landing Site Sea of Tranquility "
Location (deg,min) (0,10 N, 23,35 E) [41, p.78-9]
Time on Moon (hours) 21.53 [41, p.73]
EVA time (hours) 2.24 [17, p.337]
Range (kilometers) 0.25 "
Number of samples 58 "
Weight of samples (kg) 21 "
Crew: Edwin Aldrin second person to walk on the moon
Neil Armstrong first person to walk on the moon
Michel Collins
7.8.2.2 Apollo 12 The Apollo 12 mission Datum Source
Launch November 14,1969 [41, p.73]
Landing November 19,1969 "
Landing Site Ocean of Storms "
Location (deg,min) (3,20 S, 23,40 W) [41, p.78-9]
Time on Moon (hours) 31.50 [41, p.73]
EVA time (hours) 7.50 [17, p.337]
Range (kilometers) 2.0 "
Number of samples 69 "
Weight of samples (kg) 35 "
Crew: Alan Bean
Charles Conrad
Richard Gordon
7.8.2.3 Apollo 14 The Apollo 14 mission Datum Source
Launch January 31,1971 [41, p.73]
Landing February 5,1971 "
Landing Site Frau Mauro crater "
Location (deg,min) (3,25 S, 17,55 W) [41, p.78-9]
Time on Moon (hours) 22.50 [41, p.73]
EVA time (hours) 9.4 [17, p.337]
Range (kilometers) 3.3 "
Number of samples 227 "
Weight of samples (kg) 42 "
Crew: Edgar Mitchell
Alan Shepard
Stuart Roosa
7.8.2.4 Apollo 15 The Apollo 15 mission Datum Source
Launch July 26,1971 [41, p.73]
Landing July 30,1971 "
Landing Site Hadley-Appenines "
Location (deg,min) (26,05 N, 3,50 E) [41, p.78-9]
Time on Moon (hours) 66.92 [41, p.73]
EVA time (hours) 18.5 [17, p.337]
Range (kilometers) 27.9 "
Number of samples 370 "
Weight of samples (kg) 77 "
Crew: James Irwin
David Scott
Alfred Worden
7.8.2.5 Apollo 16 The Apollo 16 mission Datum Source
Launch April 16,1972 [41, p.73]
Landing April 21,1972 "
Landing Site Cayley Plains "
Location (deg,min) (8,45 S, 15,30 E) [41, p.78-9]
Time on Moon (hours) 71.03 [41, p.73]
EVA time (hours) 20.2 [17, p.337]
Range (kilometers) 27.0 "
Number of samples 731 "
Weight of samples (kg) 96 "
Crew: Charles Duke
John Young
Thomas Mattingly
7.8.2.6 Apollo 17 The Apollo 17 mission Datum Source
Launch December 7,1972 [41, p.73]
Landing December 11,1972 "
Landing Site Sea of Serenity "
Location (deg,min) (20,25 N, 30,35 E) [41, p.78-9]
Time on Moon (hours) 74.98 [41, p.73]
EVA time (hours) 22.1 [17, p.337]
Range (kilometers) 35.0 "
Number of samples 741 "
Weight of samples (kg) 111 "
Crew: Eugene Cernan
Harrison Schmitt
Ronald Evans
.
7.8.2.7 Cost of the Apollo program
The 1991 NASA Pocket Handbook shows the cost of the Apollo program as $20.444 billion in current year dollars [67, p.C-16]. The Augustine Report states that the Apollo program development cost was about $94.07 billion in 1990 dollars [60, p.24]. The cost of the whole Apollo program was about $116 billion in 1991 dollars [63, p.91]. 7.8.3 Current lunar projects James Asker wrote a brief report in Aviation Week [AW 51, p.44] in the 12/2/91 issue which mentioned that NASA is currently considering four lunar missions - three orbiters and one lander. According to Michael Griffin, the new associate administrator for exploration, "any one is in the $100 million class" [AW 51, p.44]. 7.8.4 Future lunar projects Several of the proposals which have been put forward by various organizations include lunar bases as part of an overall plan to establish Martian bases. We are primarily interested in projects which include cost estimates. 7.8.4.1 NASA oversight subcommittee report Richard Lewis relates the following two proposals in "Space in the 21st Century" [Ref 15]. He cites a 1966 report of the staff of the House subcommittee on NASA oversight which suggested that a permanent lunar base could be established by 1970 using the Saturn 5 - Apollo transportation system. This base would cost about $3.4 billion a year (in 1966 dollars)[15, p.103]. This would be equivalent to about $13.7 billion per year in 1990 dollars. Clearly expenditures of this magnitude are out of the question in today's budget climate. 7.8.4.2 Keaton/Gelfand proposal Lewis also discusses a proposal that Paul Keaton and Eric Gelfand of Los Alamos National Laboratory put together in January of 1982 for a self-sustaining lunar base [15, p.106]. They cited a 1968 Stanford/Ames study which described a 276 ton lunar research station which would sustain 24 people. The development costs were estimated at $17.4 billion in 1968 dollars (or about $65.25 billion in 1990 dollars)[15, p.106]. 7.8.4.3 Hoffman/Neihoff Stephen Hoffman and John Neihoff of Science Applications International Corporation presented a paper entitled "Preliminary Design of a Permanently Manned Lunar Surface Research Base" at a NASA sponsored symposium in Washington D.C. in October of 1984 [LB1, p.69-75]. This paper outlined the steps and component modules needed to establish this base. It would be occupied by up to seven astronauts. The following cost analysis was given which includes three years of operation [LB1, p.74]. * Table 7.9-1 Cost of a permanently manned lunar base ($ B)
Component Reconnaissance Surface Base
Shelter 0.1 -
Trailer(2) 1.5 -
Rover(2) 1.4 -
Permanent modules - 5.8
Chemical processing plant - 0.9
Nuclear power plant - 0.5
Lunar excursion module 2.7 1.4
Lunar logistics lander 2.7 3.6
Orbital transfer vehicles 0.8 3.0
OTV crew module 1.6 0.6
On-orbit assembly and test 1.0 -
STS recon (12 launches) 1.3 -
STS deployment (25 launches) - 2.7
STS operations (54 launches) - 6.0
Mission control center 0.5 2.1
Training/ ops development 2.0 5.0
Mission ops 0.7 3.1
Logistics 0.2 0.9
totals = 16.5 35.6
Grand total = 52.1
.
In updating this estimate we note that Hoffman & Neihoff have dramatically underestimated the cost of the space shuttle. Their estimate is about $111 million per flight. The actual cost to the US taxpayer is at least $1 billion per flight. Thus the 91 launches mentioned above (STS) would cost at least $91 billion not $10 billion. The remainder of the estimate ($42.1 billion) can simply be raised by 25.7% to account for inflation between 1984 and 1990 - giving $52.9 billion. Thus the whole project in 1990 dollars would be $143.9 billion. 7.8.4.4 Edward Teller's lunar laboratory The National Defense University sponsored a space symposium
in Washington in 1984 called "America Plans for Space". Edward
Teller, one of the original inventors of the hydrogen bomb,
presented a paper which outlined a lunar laboratory staffed by
12 people which Teller believed would cost about $1.4 billion
per year plus eight shuttle resupply flights per year. The
resupply flights were expected to deliver 240 tons of men and
supplies to the base each year [48, p.33-44].
In order to update this estimate we again inflate the 1984
dollars by 25.7% to get 1990 dollars - giving $1.76 billion per
year. Eight shuttle flights would cost about $8 billion, so the
total program would be about $9.76 billion per year in 1990 dollars
plus several billion in startup costs.
7.8.4.5 Lunar manufacturing proposal Another paper entitled "Living off the Land" by Gregg Maryniak
also appeared in "America Plans for Space" [48, p.53-80]. In this
paper several scenarios were presented for manufacturing facilities
set up on the moon. The most interesting one, "case 2", called
for a fully automated facility consisting of 15 one-ton modules
with equipment which would be supervised from earth. Initial
production would be 80 tons per year and the facility would
automatically double its production every 90 days. Fifteen shuttle
flights would be required to implement this scheme.
The cost of this proposal would be about $15 billion for the
shuttle flights and at least another billion for development of the
manufacturing equipment plus earth based operating costs.
7.8.4.6 NASA lunar base scenario One of NASA's lunar base scenarios was outlined in an article by Craig Covault in Aviation Week [AW 6, p.22-4] in the 5/11/87 issue. This plan was estimated to cost $80 billion over 20 years [AW 6, p.22] and would establish a lunar base in the 2005 - 2010 time frame. A detailed series of missions was listed: * 1. A Lunar Polar Observer satellite would be launched in 1994.
2. An unmanned sample return/rover mission was planned for 1996.
3. Larger unmanned rovers would be sent in 1997, 1998, and 1999.
4. Two manned flights per year would be made from 2000 to 2005
to establish the first base.
5. An oxygen production plant would be installed about 2005 to
provide propellant for subsequent missions.
6. The base would be completed over the years 2005 to 2010 with
four manned flights per year [AW 6, p.23-4].
.
When adjusted for inflation since 1987, the cost would be about
$92 billion in 1990 dollars.
7.8.4.7 Lawrence Livermore National Laboratory proposal [AW 53, p.84-5] Lowell Wood leads a group at Lawrence Livermore National Laboratory (LLNL) who are developing a plan which would produce permanent manned bases both on the Moon and Mars before the turn of the century and for a mere $10 - $12 billion. Highlights of this proposal are as follows. It requires no HLV. Components would be combined into 50 - 70 ton packages which could be lifted by Delta or Titan 4 rockets. A total of 24 launches would be required. The first is estimated to cost $500 million, the second $250 million, and the rest would cost $150 million each. It would use inflatable modules 15 meters long and 15 meters in diameter. Interior components would be prefabricated. A 53.3 ton LEO "gas" station would electrolyze water into its components which would be liquified to yield liquid oxygen and liquid hydrogen. In 1994 70 tons of payload would be lifted to the Moon with 215 tons of fuel from the LEO gas station. This 70 ton package would include a lunar hopper, 2 tractors, a return module with 10 tons of fuel, a "snowblower" to cover inflated modules, and a greenhouse module with food, water, and air for 4 people for 10 years. This facility would produce oxygen from Lunar soil. In 1996 a 70 ton Mars mission would leave LEO using 265 tons of fuel from the LEO gas station. It would reach Mars in 1997 after a 305 day trip. The package sent to Mars would include a return module which would be left in orbit and 4 Mars base modules including a rover, a Mars hopper, an instrument package, an oxygen from carbon dioxide machine, and a life support system for 399 days. Some of the crew would return in 1999 with Martian samples leaving the remainder of the crew. Subsequent missions would expand the facility. This proposal was not popular at NASA headquarters [AW 56, p.59] - perhaps it was too cheap. 7.8.4.8 The Ride Report In August of 1987 a report called "Leadership and America's
Future in Space" by Sally Ride was released [Ref 108]. This report
outlines four leadership initiatives: (1) mission to planet earth,
(2) exploration of the solar system, (3) outpost on the moon, and
(4) humans to Mars.
The proposal for an outpost on the moon consisted of three
phases: (1) search for a site, (2) return to the moon, and (3) at
home on the moon.
The first phase would begin with the Lunar Geoscience Observer
satellite. It would be followed by landers or rovers if necessary.
The second phase "proposes that a crew be transported from the
space station to lunar orbit in a module propelled by a lunar transfer
vehicle. The crew and equipment would land in vehicles derived from
the transfer vehicle. Crew members would stay on the surface for one
to two weeks setting up scientific instruments, a lunar oxygen pilot
plant, and the modules and equipment necessary to begin building a
habitable outpost" [108, p.30]. The crew would then return to the
space station. By 2005 the outpost would have 5 semi-permanent
occupants. Several such flights would be necessary to establish
the base.
Phase three would expand facilities to include a closed-loop
life support system and an operational oxygen production plant.
Permanent staff would reach 30 personnel by 2010.
A thinly disguised budget for this project was given [108, p.46].
It included about $45 billion for mission specific items, about $22
billion for work common to both lunar and Mars projects, and about
$21 billion for program support. This is a total of $88 billion in
1987 dollars to cover the period through 2010. Inflating by 15% to
1990 dollars we get $101 billion.
7.8.4.9 Summary of lunar proposals * Table 7.9-2 Lunar proposals Initiator Year Personnel Cost (1990 $ B) House staff report 1966 ? 13.7 per year Keaton/Gelfand 1982 24 65.25 Hoffman/Neihoff 1984 7 143.9 Edward Teller 1984 12 9.76 per year Gregg Maryniak 1984 0 16 NASA 20 yr program 1987 10-20 ? 92 over 20 years Ride report 1987 5-30 101 over 20 years LLNL (lunar portion) 1990 4 4 ? . 7.9 Financial considerations Our proposal calls for one and only one unmanned lunar mission.
This mission would place the equipment outlined in section 7.6 on the
moon via the Soviet Energia heavy lift booster. The payload placed
on the moon would depend on whether the flight went directly to the
moon in which case the delivered tonnage would be about 25 metric
tons, or whether the payload were lifted to LEO where a refueling
operation would take place before sending the payload on to the
moon. In the latter case the payload landed could be roughly six
times as great or about 150 metric tons.
Let us consider the costs of the equipment listed in section
7.6. Except for the androids and the nuclear power source(s), it is
likely that $1 million per metric ton will be sufficient to acquire
those machines. The androids will be provided by "the business" and
will therefore cost nothing. Thus we can expect that the cost of the
equipment will be no more than $25 million in the first case and no
more than $150 million in the second case - plus the cost of the
nuclear power source(s). Keep in mind that the second case requires
refueling facilities in low earth orbit. This implies that we will
develop and deploy an inexpensive earth to LEO lift capability
such as Bull's superguns before we send our first payload to
the moon. Clearly this costs money and means a major delay compared
to the first case.
In order to operate the lunar base continuously it will be
necessary to have at least three and preferably more, control centers
positioned around the world and manned by at least two sets of
operators. At 12 people per site, three sites, and a cost of
$100,000 per person per year, that would be an initial support cost
of about $3.6 million per year not counting the cost of their
communication equipment. We would attempt to share sites
associated with existing deep space networks so as to avoid the
costs of building major new facilities.
If the Earth-to-Moon EMPL were available, the lunar facility
could be rapidly expanded, perhaps even doubled every few months.
Additional units of the original equipment would be landed on the
lunar slide lander. The androids would retrieve the projectiles
and assemble the parts into working units. Additional androids
could be produced in the same way thus expanding the work force.
7.10 Financial summary In contrast to most other proposals, our proposal requires only one unmanned mission to establish the first permanent lunar base. This base would be operated remotely from earth from a set of three faclities located about 120 degrees apart around the world. The estimated cost would be: * Item Est. cost ($ M)
Development of lunar equipment 25
Communication equipment 2
Nuclear power sources 15
Energia delivery to the moon 750
------
$792 M + $3.6 M per year
.
7.11 Political summary
7.11.1 The first lunar base 1. The base should be located on a northern mare on the near
side of the moon - perhaps the Mare Frigoris. This will allow
relatively easy access to the north pole of the moon which will be
the site of the second lunar base. This location will also allow
the construction of a small electromagnetic launcher with the
proper geometry to launch projectiles back to earth from the site.
2. The first base should be entirely robotic and would be
operated remotely from earth. Only one soft landing on the moon
would be required to establish this base. The required equipment
is listed in section 7.6. At least three supporting facilities
will be required, spaced equally around the earth.
3. Subsequent materials would be delivered to the lunar base
by "throwing" them to the moon with an electromagnetic launcher
(EMPL). This launcher would cost about $6 billion and would be
paid for by a group of utilities and/or oil companies - who would
be repaid in helium-3 from the moon. This is the cheapest method
of delivering materials to the moon (less than $2000 per kilogram)
and since it uses so little propellant neither the earth nor the
lunar vacuum will be significantly effected/polluted.
4. A lunar slide lander will be contructed at the first base
to assist in the landing of materials "thrown" from earth (see
section 7.2.3 in the LSL). The LSL is the cheapest and simplest
method for landing material on the moon and it requires very little
propellant to be exhausted into the lunar environment.
5. Lunar oxygen delivered to LEO will not be economically
competitive with water/ice lifted from earth until it can be lifted
off the moon without rockets. In other words, once the small EMPL
is built at the first lunar base (see section 7.4), then lunar
oxygen could be thrown down to earth at competitive prices - perhaps.
7.11.2 Helium-3 1. Helium-3 is the ultimate fuel for the 21st century.
We must find an alternate fuel to oil because it will be
exhausted by the middle of the 21st century.
2. Helium-3 is worth at least $1,000,000,000 per ton.
This fuel is available on the surface of the moon. The
moon's surface is estimated to hold at least a million
tons of helium-3. There is sufficient helium-3 on the
moon to power human civilization for 1000 years.
3. Helium-3 is not radioactive and nuclear fusion
reactors do not produce radioactive products thus nuclear
fusion reactors using helium-3 are environmentally safe.
4. Helium-3 will reduce the greenhouse effect on earth.
Millions of tons of carbon dioxide are injected into our
atmosphere every year by our fossil fuel burning power
plants. They can be replaced by helium-3 plants thus
reducing the output of greenhouse gases.
5. The nation which harnesses helium-3 will dominate the
21st century. That nation will have unlimited low cost
power while everyone else will have to pay higher and
higher prices for disappearing oil.
6. Helium-3 is a can't lose proposition. It's profitable,
necessary, and environmentally safe. Will we go for it or
just watch while others go get it?
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