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I tried not to make you mad, but we apparently have an insoluble problem.

I did not get mad per say, lets call it a bit annoyed. :-)

It was this comment: “boy, you have a hard head. Don't ever get into business or management.” That got me a bit miffed so to speak. My apologies for letting my emotions get in the mix.

Let me digress for a moment. On a previous thread on UFO’s, I was called “the ultimate skeptic”. An individual was describing a UFO experience and I posted that it was not necessarily aliens. As a matter of fact, I also posted that Occam's razor pretty much dictates these are not alien craft snooping around in our skies. (Why I brought this up I will make clearer further down my post)

-First lets get a few definitions out of the way since I am going to use then throughout my post-:

Occam's Razor – one should not make more assumptions than the minimum needed.

Principle of Parsimony – a criterion for deciding among scientific theories or explanations. One should always choose the simplest explanation of a phenomenon, the one that requires the fewest leaps of logic.

Objective – undistorted by emotion or personal bias; based on observable phenomena; "an objective appraisal"; "objective evidence"

Subjective – taking place within the mind and modified by individual bias; "a subjective judgment"

Sophistry – a deliberately invalid argument displaying ingenuity in reasoning in the hope of deceiving someone

Solipsism (noun), Solipsistic (adjective) – the belief that only one's own experiences and existence can be known with certainty

Cislunar – situated between the earth and the Moon

Lagrange Points – places where a light 3rd body can sit "motionless" with respect to 2 heavier bodies that are orbiting each other thanks to the force of gravity. (There are five)

Regolith – The layer of loose rock resting on bedrock, constituting the surface of most land. Also called mantle rock

Hohmann Transfer Orbit – a Hohmann transfer orbit is the most efficient intermediate orbit to transfer from one circular orbit to another. The transfer orbit is an ellipse with periapsis at the smaller radius and apoapsis at the larger radius.

Delta-V – delta indicates change and V stands for velocity. Change in velocity refers to both the speed of the craft and the direction.

Isp (specific impulse) – The amount of thrust produced from each pound of propellant per second.

Mass Fraction – The mass fraction is a measurement of a rocket’s efficiency. The mass of the propellants of the rocket divided by the total mass of the rocket gives mass fraction.

Planetesimals – A rocky and/or icy body, a few kilometers to several tens of kilometers in size, that was produced in the solar nebula.

Roche Limit – The Roche limit is the minimum distance to which a large satellite can approach its primary body without being torn apart by tidal forces.

Tidal Lock – Tidal drag from one orbiting body on another causes the two bodies to “lock” to each other. This is why the Moon keeps only one side to the Earth. (a further explanation will follow later in this post)

Angular Momentum – A quantity obtained by multiplying the mass of an orbiting body by its velocity and the radius of its orbit. According to the conservation laws of physics, the angular momentum of any orbiting body must remain constant at all points in the orbit. Thus planets in elliptical orbits travel faster when they are closest to the Sun, and more slowly when farthest from the Sun. A spinning body also possesses spin angular momentum.

Isotope – An element with the same atomic number but having a different atomic weight (i.e. more or less neutrons)

Now that we have a few definitions under the belt, let us continue.

Think back a little more than 500 years. Many people still believed the world was flat, the world was only 6000 years old, the Earth was at the center of the universe, etc. However, the time was ripe for not only huge leaps in knowledge, but in exploration as well.

Europe was changing. Natural resources and newly exotic items (especially from the far east such as spices, drugs, silk and china) were all the rage. During this time land based trade routes were established, however, they were long, costly, and difficult. Water routes were attempted including one funded by Ferdinand and Isabella in 1492. It so happened a trade route to the orient was not forthwith, however, an entire new continent was “discovered” (at least to the Europeans).

Here is where it gets interesting. Countries in Europe (mainly Spain, France, and England) looked to this new land, not for colonization, but the abundance of natural resources. Think of what came back from the new world, sugar cane, rubber, gold, silver, furs, timber, cocoa, etc. So not only were these voyages of discovery, but voyages that ultimately lead to trade and wealth.

It took close to 100 years from the voyages of Columbus to the establishments of colonies. Were they able to produce all of the things needed for a society? Not hardly. However, with natural resources being shipped back to the old world and manufactured goods shipped to the new, it turned out to be quite profitable for the nations (and companies -the East India Rubber company comes to mind-) involved.

What I am driving at is that you don’t “need” all of the 4000 years of technological infrastructure to produce a successful colony. If we do establish a lunar colony, the raw material from the lunar regolith may generate enough wealth to make a lunar colony worth the effort.

I am looking back over some questions brought to mind on this thread. One of those was:

Just how are you going to create, on the moon, the infrastructure to build a space ship to take advantage of its low gravity?

When the first sailing ships visited the new world, did they make those ships there? On the other hand, there were enough raw materials to build them and eventually they did as those colonies flourished into the great metropolises we have today.

Ok, let us take a look at the Moon. 1) How was it formed, 2) what is it made of, and 3) how far away is it are some of the questions that must be answered prior to the contemplation and planning of a colony and subsequent exploitation of the material found up there.

1) How was the Moon formed?

There were at least five major ideas that were proposed as to the formation of the Moon.

Fission – The Moon split off from the Earth.
Capture – The Moon was captured by the gravity of the Earth.
Condensation – The Moon coalesced out of the same “stuff” the Earth did.
Colliding Planetesimals – Formed from colliding Planetesimals during the early formation of the solar system.
Collision – A body collided with the Earth causing a piece of the Earth’s crust to form the Moon from a resultant ring produced by that collision

The evidence points to the collision theory. First, the Moon does not have an iron core. This pretty much rules out that it coalesced from the same cloud of debris that the Earth did. Second, throughout the solar system, the oxygen isotopes have been found to be different. If the Moon were captured, it too would not match the Earth’s oxygen isotope ratio (which it does). Fourth, by looking at the angular momentum and energy required, the theory that the Moon spun off the Earth after the Earth formed does not hold up.

This leaves us with the Collision theory as the best model we have for the formation of the Moon. The resultant collision caused a ring of debris from the Earths crust to form outside the Roche limit. If it had not, tidal forces would have not allowed for the Moon we see today.

A more in depth discussion of tidal locking since the Moon is tidal locked to the Earth. The reason the Moon keeps one face to the Earth (Its rotation on its axis matches the period of its orbit) is it is tidally locked to the Earth. Here is a more in depth explanation. The total angular momentum of the earth moon system, which is spin angular momentum plus the orbital angular momentum, is constant. (The Sun plays apart also) Friction of the oceans caused by the tides is causing the Earth to slow down a tiny bit each year. This is approximately two milliseconds per century causing the moon to recede by about 3.7 centimeters per year. As the Earth slows down, the Moon must recede to keep the total angular momentum a constant. In other words as the spin angular momentum of the earth decreases, the lunar orbital angular momentum must increase. Here is an interesting side note. The velocity of the moon will slow down as the orbit increases.

Another example of tidal locking is the orbit period and rotation of the planet Mercury. What is interesting about this one is that instead of a 1:1 synchronization where Mercury would keep one face to the Sun at all times, it is actually in a 2/3:1 synchronization. This is due to the High eccentricity of its orbit.

There also can be more than one body “locked” to each other. Lets take a look at the moon Io. Io is very nearly the same size as the Earth’s moon. It is approximately 1.04 times the size of the moon. There is a resonance between Io, Ganymede, and Europa. Io completes four revolutions for every one of Ganymede and two of Europa. This is due to a Laplace Resonance phenomenon. A Laplace Resonance is when more than two bodies are forced into a minimum energy configuration.

2) What is the Moon made of?

From here http://lunar.arc.nasa.gov/science/geochem.htm

“Primary elements: The lunar crust is composed of a variety of primary elements, including uranium, thorium, potassium, oxygen, silicon, magnesium, iron, titanium, calcium, aluminum and hydrogen. When bombarded by cosmic rays, each element bounces back into space its own radiation, in the form of gamma rays. Some elements, such as uranium, thorium and potassium, are radioactive and emit gamma rays on their own. However, regardless of what causes them, gamma rays for each element are all different from one another -- each produces a unique spectral "signature," detectable by an instrument called a spectrometer. A complete global mapping of the Moon for the abundance of these elements has never been performed.

Hydrogen and helium: Because its surface is not protected by an atmosphere, the Moon is constantly exposed to the solar wind, which carries both hydrogen and helium -- each potentially very valuable resources. One natural variant of helium, [3]helium, is the ideal material to fuel fusion reactions. When scientists develop a more thorough understanding of fusion, and can practically implement such reactions, the Moon will be a priceless resource, since it is by far the best source of [3]helium anywhere in the Solar System.”

This pretty much answers the question; are there valuable materials up there?

3) What is the distance to the Moon?

The mean distance to the Moon is approximately 238,800 miles. From past experience, we can design spacecraft to get there in about three days. This is far shorter than the months the early voyages took to the new world.

Final thoughts on the Moon.

So here we have this tremendous resource at our fingertips. Unfortunately (not unlike the early explorers), the initial cost is staggering. However, in the long run it would end up being an invaluable resource for both material and scientific study. One of the big advantages is that the Moon keeps one side facing the Earth. This minimizes communication problems between the two bodies. Also since the backside of the Moon is shielded from the Earth, it would be an ideal spot to place a radio telescope array.

What about the rest of the solar system? Can we travel from one planet to another with out requiring non-existent technology such as antigravity? The short answer is yes.

Basically, to get from one planet to the other, a Hohmann transfer orbit can be used. In simple terms (for planetary missions) this is an orbit around the Sun that intersects the two planets in question. First you launch you vehicle into a stable orbit around the planet you are leaving. Then you accomplish a delta-V to insert the spacecraft into the transfer orbit. At you destination you accomplish another delta-V to place the spacecraft into orbit around the final planet. This type of transfer minimizes the acceleration required at both ends of the orbit to match speed with the planets involved.

If for some reason there is not enough energy to produce a direct transfer orbit, another planet may be used (gravity-assist) to add the energy required to accomplish the mission. The Galileo was sent to Jupiter using this method. (After the Challenger disaster, an IUS was substituted for a Centaur reducing the total energy, which subsequently forced a redesign in the mission profile to use Venus as a gravity-assist).

One of the disadvantages of a Hohmann transfer orbit is it is quite slow, especially for the outer planets. So a series of gravity-assists can be used. Not only does the vehicle get to the destination in a shorter time, you can "explore" the planets you are gravity assisting from in the process. Voyager did this very thing as it left the solar system.

Since we are talking now about colonizing the Solar System, we should take a moment and talk about the Lagrange Points.

There are five Lagrange Points in the Earth Moon system. The one that is most talked about it the L5 point. In fact there was a society called the L5 society named after that point. The L4 and L5 points are stable. Meaning there would not have to be periodic Delta-Vs for repositioning. The L5 was chosen since it trailed the Moon and it is thought that the Moon would “sweep” up any debris that may be a hazard to the station.

”Whew!!!!!!!!!!!!!!!!!!!! Part 2 Tomorrow”