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Quantum_Conundrum
This thread is being started to discus an age old topic of moving human civilization beyond the earth as our (descendents) food and energy needs become greater than what can be obtained here on earth.

This section is not intended to introduce new concepts, but rather just a brief synopsis of ideas presented in various works of both science fiction and realistic proposals made by forward thinking individual.

Dyson Sphere

The reader can search the wikipedia page for a brief overview of Dyson Spheres.

The holy grail of space colonization would be the Dyson Shell, if it is at all possible to construct such a thing. In any case, a true Dyson Shell would require hundreds of millenia to construct to completion. The advantages of a Dyson Shell is that it would allow a civilization with population in the trillions, possibly even quadrillions, to harness the entire power output of a dwarf or main sequence star to power that civilizations technologies and its biosphere. The people literally live in the megastructure, and the solar radiation is absorbed through heat and through solar panels and even the solar wind is captured and used.

Even though similar megastructures have been proposed as early as the 1930's, to this day we still do not have materials capable of construction of a true Dyson Shell. Completion of a Dyson Shell, or a total net power usage equivalent to this, would constitute a civilization being classified as Kardashev Civilization Type 2(see wikipedia). Currently, all of humanity combined does not yet even rank as a true Type 1 on this index, but has been classified as approximately Type "0.72", as far as current knowledge of potential energy sources on earth are concerned.

Just as some points of reference, the "Galactic Empire" in Star Wars is approximately on the lower end of a Type 2.x Civilization, though they do not have a Dyson Sphere, they do have a total power output greater than one star's worth of power. The Borg in Star Trek are most likely on the low to mid level of Type 2.x civilization.

In order to construct a Dyson Sphere and its respective biospheres where people would live, effectively the civilization must mine out all of Mercury and Venus, as well as the gas giant planets and asteriod belts and the moons and dwarf planets for the materials that would be needed. Additionally, most of the helium and some of the hydrogen from all these planets would need to be fused to make heavier materials and oxygen to support life. This will all be discussed in detail later.


A Dyson Ring encircling the Sun at 1AU and having a width of 2 earth radii would have a surface area of 93,819.72 times greater than the cross sectional disk of the earth, thus receiving that many times as much total solar power as the earth! Because the cross sectional area of the earth is only 1/4 the surface area, this is actually enough energy to support 375,278.88 earth biospheres(assuming full Type 1 civilization of Earth), for eons and eons, and it is still only a tiny fraction of the total power output of the Sun!

Ok, so a true Dyson Shell or even a true Dyson ring are currently far, far beyond both our means and our needs as a race. Thus there is little point in thinking about the specifics of such a megastructure any time soon, other than to realize that at "some point" in the distant future such structures will become far more efficient than terraforming planets or the other options I am about to discuss.


I take a pause here
Cusa
The resources necessary to take the first step to put a station on the moon is too much to be practical.

Space colonization is not a way to population sustainability.

It needs to be pointed out that it is not. People haven't really given it much thought if they think it is anywhere near realistic.

Mitch Raemsch
Quantum_Conundrum
Cusa:

Hear me out, friend, because there are variables you have not yet considered. There are vast, vast resources avaible "hidden" in the solar system, we must simply be willing to do what is necessary to obtain these resources.
Cusa
Getting those resources is still too impractical.

Mitch Raemsch; Falling light in gravity changes colour
FGG
QUOTE (Cusa+Dec 10 2008, 10:12 PM)
Mitch Raemsch; Falling light in gravity changes colour

Time for the meds?

FGG
Cusa
You should take yours. You will see the gravitational rainbow.
Quantum_Conundrum
Europa: The Key to colonizing Mars, Neptune and Uranus.


According to NASA, the Jupiter's Moon Europa is believed to be covered in about 100km layer of liquid water and water ice. I have taken the liberty of calculating the volume of this much water.

2.901*10^9 km^3 of water!
or
2.901*10^21 liters (or kilograms) of water

or

1.6117*10^23 Mol of Water

or the equivalent of

1.6117*10^23 Mol of H2 gas plus 8.053*10^22 Mol of O2 gas.





In fact, according to my calculations, there is more than enough water on Europa to use for terraforming Mars, as well as providing all the liquid water needed for the biospheres I will shortly discuss for Neptune and Uranus (several millenia from now). Some of this water can also be used to create rocket fuel and also for Nuclear fusion. The oxygen will be used in the biosphere on mars and eventually both Neptune and Uranus.

From Wikipedia Fusion article
QUOTE
Fusion power commonly proposes the use of deuterium, an isotope of hydrogen, as fuel and in many current designs also use lithium. Assuming a fusion energy output equal to the 1995 global output of about 100 EJ/yr (= 1 x 1020 J/yr) and that this does not increase in the future, then the known current lithium reserves would last 3000 years, lithium from sea water would last 60 million years, and a more complicated fusion process using only deuterium from sea water would have fuel for 150 billion years




Actually Terraforming Mars (Sort of).

Earth's moon does not make a good candidate for terraforming nor long term living, because its surface gravity is far too low to be of long term habitation. Additionally, there simply aren't any available "human needs" resources on the Moon as far as we know from current knowledge.

Notice, all "buildings" and "transportation mechanisms" discussed here are designed in a way that they are "air tight", unless otherwise specified. WE don't want to waste any energy, and the atmosphere of mars is mostly CO2, which we will eventually harvest for usage in our biodomes (archologies) to feed to plants in the artificial biosphere.

Essentially, we are encasing the entire surface of the planet in a shell of metals, glasses and polycarbonates. Most of the materials for this project come from the planet itself and the asteroids and minor moons. This is done so that our precious oxygen cannot escape, and because the way I have imagined to do this, it becomes a natural consequence of the most efficient construction process and civilization development anyway.

Because the surface gravities and escape velocities of Mars, Europa, and the various minor moons and dwarf planets are so low, this means we can very, very easily move enormous payloads from planet to planet or moon to moon (except in the case of earth). In fact, based on my estimates, launching a spacecraft from the surface of Europa requires only about 2.43% as much total energy as launching the exact same spacecraft from the surface of the earth. In other words, a rocket system with the same total energy of the existing space shuttle could launch a ship and payload 41.15 times as massive from the surface of Europa using the same amount of fuel.

Launching the same craft (with different, but equal mass payload) from the surface of mars requires approximately 16.9% as much energy as launching it from earth.

This means that it would be possible to construct massively efficient transport mechanisms between Mars and Europa. The scientists now tell us that Mars has some usable water trapped in its poles which could be used for drinking and also for fusion. however, this is a really small scale operation by comparison of what I am going to suggest.

Europa has about enough water to completely cover the entire surface of Mars to a depth of about 12.5km! We do not need ANYWHERE near that much water on mars. We don't need oceans that support 10,000,000 species of obscure creatures. We don't need, or even want, obscenely deep ocean trenches. We want manageable artificial oceans, whether freshwater or salted, which can be farmed as needed and complement a stable biosphere. These "artificial oceans" are contained in air tight arcology structures, and the primary energy source which powers this biosphere is nuclear fusion, with solar radiation coming in a distant second.

We need man made oceans in biodomes and archologies which support algaes, plankton, and the fish that feed on these, as well as edible "bottom feeders" such as oysters, etc. Along with the land based crops grown in biodomes during the early epochs of the martian colonies, these man made oceans would serve our needs well, coverting CO2 and other less useful materials efficiently into food supplies and oxygen for us. Electricity from Fusion powers lamps which provide the energy for these oceans, in addition to pumping in the water carrying "waste heat" from the fusion reactions. Thus maintaining survivable temperatures for the entire artificial ecosystem. Eventually the artificial oceans fill up the entire basement level and several other levels of the megastructure. This is one possibility anyway. The power from the sun is converted to electricity and ambient heat through solar cells or other process. The power from fusion however, is the primary source of energy which powers this artificial biosphere.

Because Mars is so far away, it recieves only about 43% as much sunlight per square meter as the earth does. This is the second to last planet that receives enough sunlight to even be worth mentioning, with Jupiter receiving about 1/27 as much sunlight per square meter as the earth. Now, this means that the sun alone cannot provide enough energy to sustain "normal" earth-like life on Mars. This is not really a problem, however. With all that hydrogen from Europa, we can use fusion to provide ambient heat, light, and electricity to our civilization, and indeed, the entire biosphere. Hydrogen fusion eventually leads to the production of carbon, nitrogen, oxygen, and even iron. These are all good things as they are used to feed the biosphere or to build structures.

In the special case of Mars, because it is a terrestrial planet, we will build a ring on the surface of the planet starting at the poles and wrapping around perpendicular to the equator. (we need to blast away any mountain ranges in the way, and fill in any valleys. But since we need billions of tons of metals and agregates anyway from the construction of this megastructure, we would need to do that anyway.

The reason we want to build the polar ring first on mars is because the water appears to be most concentrated on the poles. With this ring filled with pipes and with all the living quarters, we can mass transport materials, namely water, hydrogen, oxygen, nitrogen, carbon dioxide and other liquids and gases through sorted piping networks with almost no net energy cost. With forward thinking, a series of valves and T's are installed in the most likely places ahead of time(i.e. where each ring intersects another right, as well as equidistantly along those rings, say every kilometer or ten), so that future projects already have their infrastructure laid out for them. (Unlike the U.S. government, anyone embarking on this project would actually give a damn about future generations.)

Because we need not be concerned with established "traditional" city, suburb, urban structure (or lack thereof) as on earth, we can start with an "ideal" organized layout of transport mechanisms for the surface of Mars. The second ring is installed on the same plane as the martian equator, perpendicular to the first, and the third ring is another polar ring perpendicular to both rings one and two.

The equatorial ring is designed such that its transport mechanisms pass over the top of the other two. Each ring will use some sort of mass transport such as monorails or maglev as follows. There are about 2/3 of the tracks in the center of this massive transport mechanism, used for transporting solid goods and people(as stated, liquids and gases are simply piped around the planet as needed). One third of the total tracks on the equatorial ring move only to the east. The other 1/3 move only to the west. The remaining 1/3 of the tracks have the ability to turn onto the polar rings tracks going north or south, eventually reaching the junctions at the poles and turning back. Essentially, trains only move in one direction, because they either circle the entire globe, or else circle one half of one quadrant of the globe. Further, we could add two more smaller rings parrallel to the equator, but roughly half way to the poles, but behaving the same way as the one at the equator.

A computer knows where each compartment of a train/maglev/whatever needs to stop, thus moving the train (preferabily some sort of planetary scale magnetic ring shapped sled) only as needed. In this way materials at the equator are transported with almost no net energy cost. The computer program would know based on a human entering in the cargo start point and its destination when and where to stop the rotation for each destination. This is technology similar to what Amazon.com currently uses in its warehouses, only this would be on a global "megastructure" scale.

Homes, farms, factories, and other businesses and industries are built in Archology structures, along with farms and artificial oceans. Most jobs in this civilization, especially during the first several centuries, would be related to farming or construction of the polar and equatorial rings. Once these structures are in place, population of the planet in archologies built along and outward from this rings, filling in the 8 major zones between them, would be incredibly easy and efficient. The top floor of all buildings covered in solar panels.

Due to the low surface gravity of Mars, it would be possible to construct buildings as much as 3-5km tall or more, which can eventually house hundreds and hundreds of thousands of people per square kilometer of land area. It is much more cost effective and energy efficient to build structures that are more cubicle as opposed to flat or sky scrapers, particularly when everything should be absolutely "air tight". Thus we might consider a building which is 3km*3km*3km in size, having a footprint of 9km^2 and a volume of 27km^3. These would be constructed in a modular fashion along the rings as human needs demand, with further individual modular transport mechanisms which tie into the primary ring structures. Eventually the entire surface of mars would be covered in these.

Thus we "terraform" mars, but not in the science fiction manner, but rather in a realistic manner. When we need oxygen, simply suck the CO2 out of the atmosphere and feed it to plants and algae, trapping the Oxygen INSIDE the megastructure, which coats the entire surface of mars (eventually). Most of the building materials for this structure come from Mars itself, or else from teh martian moons and the asteroids.

Between Earth, Mars, Europa, and the asteroids, dwarf planets, and minor moons, this stage of civilization could support theoretically upwards of 25-50 billion human beings. About 12 billion on earth, and about another 12-25 billion or more on mars, easily (see below).

The reason mars could possibly support more life than earth, even given our current technologies, is because of the lower gravity. Mar's gravity is high enough to actually be "human friendly," but low enough for the constructure of truly mega mega structures. Everything, organic and non-organic, would work far more efficiently, and you could just build bigger, better, safer more efficient structures. One advantage Mars has over the Earth's moon is the fact that it already has a huge amount of oxygen, water, and other organic compounds and elements on the planet in one form or another.

A 3km high building might have 600 - 1000 floors. A 1km high building might have 200-333 floors. Imagine if the entire surface of the planet were covered in these modularly over centuries or millenia (essentially 200-1000 concentric spheres). Though it may not actually be possible to establish a stable artificial ecosystem that massive, nevertheless, the human population that could potentially live here even with existing technologies, in equilibrium wiht a biosphere of plants and animals populated from earth, (plus fusion,) is certainly in the tens of billions.


Remember, there is literally about a couple hundred times as much water as this civilization will ever need sitting in Europa.

Techniques and technologies developed during this phase of human civilization would come in quite useful during the next phase.


If only I could draw a diagram of what I have in mind for Mars, but I don't know of any CAD software that supports and adequate scale, and there is nothing I know of other than video game development software that supports drawing the 3d the way I'd need to do anyway.
Quantum_Conundrum
Cusa:

Getting resources is only "Impractical" if you view economics in terms of strictly "what benefits Earth".

However, in the greater scheme of things, "What benefits humanity's survival".

It is true that during the first several decades, or perhaps even first several centuries, earth would have very little direct benefit from colonizing space. However, as human population swells and understanding of physics and technologies increase, this may go up. Certainly, in the long term, the Earth humans benefit simply by communication and sharing of technological advances.



Titan, Europa, and the inter-Planetary Fuel Highway

Here I will consider the mining of fuels and water from several of the planets and their moons during the "early years" of space colonization.


As previously discussed, Europa is a motherload of all the water humanity will need for a total population eclipsing perhaps several hundred billion many millenia from now!

This water is relatively easily accessible since it is right on the surface of the planet in ice and liquid form (under the ice,) and because of the planet's low surface gravity.

Saturn's moon Titan is known to have "Hydrocarbon lakes" at its poles, as well as a methane atmosphere. This makes Titan a perfect source of fuels to complement the hydrogen and oxygen mined from Europa. However, it may or may not be needed, depending on what other resources are available on Mars and the other moons and asteriods.

Based on some rough estimates, the total amount of energy needed to escape Titan's gravity is only about 3.29% that of earth. (surface gravity 1.352m/s2, escape velocity 2.639km/s). This means that our existing space shuttle could basicly burp the engines and escape from the surface of Titan! The space shuttle is not at all well suited for this mission, I'm just making the comparison.

As previously mentioned, the total energy needed to escape Europa is incredibly tiny compared to earth, just 2.43% of earth.

This means it should be possible to harvest fuel, water, and oxygen from Titan and Europa with a significant net gain and bring it to Mars. Later on, perhaps a few centuries in the future when a fully functioning industrial system is established on Mars, Europa, and Titan (refining and so on are done "on site" whenever possible, to save on mass that must be transport.) Once this is obtained, over time "excess" fuel can be shipped to earth in enormous capsules manufactured on Mars or the Moon or asteroid fields. Basicly, these would float down with Gigantic Parachutes. If Earth is using hydrogen fusion by then, Water could even be brought in from Europa to replace the water that is being fused, in which case capsules wouldn't even be needed, just drop a big chunk of water-ice in the middle of the atlantic or pacific from space. As long as the cargo ship doesn't actually land on Earth, most of the fuel costs of "lift off" from earth are avoided.

Eventually, ships would only launch from Earth to bring colonists to other planets, by the thousands per ship eventually, as people are willing!



How it works:

Water, hydrogen, and oxygen is harvested from Europa and brought to Mars and Titan, or even earth(drop it from space over the ocean).

Methane and other hydrocarbons are harvested from Titan and brought to Europa and Mars as needed for rocket fuel.

When a ship is flying on a course from anywhere to Titan, it uses only enough fuel to coast to Titan plus enough for minor course corrections.

When a ship leaves Titan to anywhere, it brings a full cargo hold and fuel tank full of the hydrocarbon fuel. (plus personel if people are leaving Titan.)

When a ship leaves Europa to anywhere it brings a full cargo full of water, plus enough fuel to get back to Titan. Early on, Ships leaving Europa for Mars do not even need to land on mars, unless they need supplies from Mars. Just as on earth, simply drop the shipment of water in a safe zone, and turn around and fly back, once again, avoiding most of the "lift off" costs. The block of water-ice is then cut up and loaded on trucks or whatever, and hauled to the processing plants as needed.

Food grown on Mars is shipped to the work colonies on Europa, Titan, and other places (which also have their own artificial biospheres, but much smaller, being primarily mining operations.)

Now, as stated, the Space Shuttle is by no means suitable for this operation as it is designed to enter earth's thick atmosphere, among other things, which these transport vessels I am discussing will mostly not need to do. However, just using the example of the Space shuttle and it's relatively pathetic size cargo bay, we can get an idea of how much water a future system might be able to transport from Europa on a single trip.

From Wikipedia regarding the space shuttle:
These numbers assume earth gravity and earth atmosphere conditions, but we shall play along with this.

Gross liftoff weight: 109,000 kg (240,000 lb)
Maximum payload (by mass): 25,061 kilograms (thus it could lift 25 cubic meters of water from Earth to orbit.)

Now, let us consider this. We lift off from Europa. All the propellant we burn falls gradually back to the planet, mostly as Nitrogen, Carbon Dioxide, and Water(which we then harvest again)! (At first, this appears to have done nothing, but this will be explained later.) The water payload we are carrying to Mars represents. 1388889 Mol of Water. Or 2777778Mol of Hydrogen, representing as much as 4.7173E18Joules just from the H+H reactions (more than ten times the energy the earth receives from the Sun in one year). Plus we gained (22,222Kg) 694, 444 Mol of Oxygen(O2) on Mars. But remember, since the gravity of these planets and moons are so low, the SPACE SHUTTLE could actually ship far more water than this per trip in its cargo hold (the stats for max cargo capacity are given by mass, and assume a launch from earth. If you were launching from Europa, you could simply fill the entire cargo bay with water-ice).

A vessel specifically designed to do this could land on Europa, get fueled with liquid oxygen and liquid hydrogen, or some combination of rocket fuels produced from the stuff from Titan, (I'll let the rocket scientists figure that out.) Next, lift off with a huge payload of perhaps hundreds or thousands of cubic meters of water. Next, fly to mars, or Earth or some other planet or space colony eventually, and drop this in a "safe" zone, then turn around and fly back.

Thus, fusion reactions provide all the heat, electricity and mechanical energy humanity would ever need for eons and eons. Europa and other moons and comets provide all the water needed to support the biology, chemistry, and fusion for all humanity. No matter how ineficient any rocketry processes may be, you always end up gaining water and free Oxygen (and carbon from Titan) to Mars or any other destination planet or space station through this process. Thus 25000kg of water is enough to power an entire Mars biosphere with human population in the billions for well over a decade ( actually, millenia or even centuries early on when population is only a few thousands to less than 1 billion humans), and the only "waste" products are heat and pure oxygen, both of which you need and want anyway.

Whatever costs there are in terms of Chemical energy to move the water from Europa to the Earth and Mars and the other planets where you want it is really insignificant compared to the energy produced by the hydrogen and later helium based fusion reactions. The total amount of energies represented by the rocket fuels is insignificant and easily recoverable through various processes, particularly since the propellants mostly just fall back down to the surface of the planets and moons, eventually, where they can just be harvested again.


This economy(for lack of a better word) assumes Hydrogen Fusion is doable.

On earth, much of the energy of Nuclear reactors is considered "lost" because much of it ends up being "wasted" due to various things. Generators and their turbines are less than 100% efficient, etc. Here, "waste heat" is considered a pollutant because it damages rivers and so on.

However, even though earth already has enough hydrogen and lithium and other possible reagents for fusion, reportedly about 150 billion years worth, eventually earth would need to start "importing" water, especially hydrogen, from Europa and other outter solar system planets and moons, or risk destroying its own biosphere(electrolysing all the water).

On Mars, Europa, and Titan, Hydrogen Fusion would effectively be 99.9% efficient.

Why? Because there, even the majority of the "waste heat," is doing something useful: Providing heating throughout the colonies.

When you think about it, with fusion, Europa and Titan would basicly become almost a "bottomless wallet" in terms of total energy potential for at least the next several millenia. In fact, for at least several millenia, More carbon and water from these moons would eventually be needed to sustain the physical growth of the biomass of the civilization itself, rather than to produce the heat and electricity energy the entire human civilization needs!

That number listed above, i.e. hydrogen from 25m^3 worth of water providing energy equal to ten times that recieved by the earth from the sun in a year, well, this means that Europa can provide all the water, oxygen, heat, and electricity for a civilization spanning all the planets and moons, eventually numbering perhaps even in the trillions for countless millenia! Surely, by then, if anything resembling a Dyson Sphere, Ring, or Swarm is at all possible, humanity would discover how to build it!
Quantum_Conundrum
A re-examination of the Earth's Moon(a.k.a. "Luna") as an actual permanent civilization.


Earlier, I largely dismissed "Luna" as a primary colony of residence on the grounds that there are few known resources available. This does not necessarily mean that Luna isn't more favourable than other planets in the Solar System, its just a bit more tricky for the reason I am about to list.



Pros: (these are mostly double edged swords, however)

-"The Moon" averages the same distance to the sun as Earth, which means it receives the same amount of solar energy per square meter as the earth. In fact, when you consider there is no atmosphere to deflect sunlight, the Moon actually receives more Solar Energy per square meter than the earth. Consequently, covering the surface of the moon in Solar Panels Can produce a significant amount of energy for the base and civilization here.

- Very low gravity, making it efficient for launching spacecraft to other planets and moons (assuming there are any resources on the Moon worth mining to send elsewhere).


Cons:
- Radiation.
Because of Luna's proximity to the Sun, and because it has almost no atmosphere, and not much of anything else to protect it from solar flares and storms and other radiation, this becomes a major hinderance to any moon base or moon colony. Effectively meaning that any attempt to colonize Luna requires is very rapid mobilization to build a habitat(initially under ground) to maximize the protection from radiation.

-Gravity.
The gravity on the moon is so low, it may not be healthy for human's muscles and bones. Admittedly, Mars is only slightly more than 1/3 that of earth, and Europa and Titan actually have less gravity than Luna, so this may not even be a real issue.

- No Atmosphere.
Luna has almost no appreciable atmosphere, which as previously mentioned is very dangerous. Even a dust sized meteor could be deadly to any colony structure on the surface of the moon. While Europa and Titan largely have this same problem, the difference is they are far less massive and less likely to attract a meteor, and additionally, they have a larger "return" for their investment, as far as the known resources available on them. Additionally, there are "tricks" I have throught of for using Mars' atmosphere to our advantage in terms of either disipating heat waste, and/or feeding it to plants (Oxygen + food for humans). Luna simply does not have this option, as far as we currently know, so colonizing Luna involves literally "importing" not only water, but CO2 (for carbon for plants.)



Taking all of these things into consideration, colonizing Mars literally is easier than colonizing Luna, in spite of the increased distance from the Sun and the Earth.
Quantum_Conundrum
What does "Earth" gain from all of this?



Of course, this is the big question any naysayer, including myself, has regarding all of this.


Well, this question really just depends.

What did the U.K. gain out of colonizing America? Well, initially much raw materials. Of course, they tried to control everything and make the colonies around the world into their slave states, which ultimately led to revolution. Hopefully "Earth" in the future learns from these mistakes, otherwise we could end up facing a true "War of the Worlds," and earth may inevitably lose!

But what does Earth gain?

-Knowledge.
Increased total human population increases the probability of discovering new technologies which can benefit earth throughout the millenia, even if there never is a net "material" benefit. But there will be a net material benefit, as I will discuss.

-Water and hydrogen.
Eventually, barring some world war or mega-disaster, human civilization on earth will grow beyond the capacity of the earth's biosphere to support merely on the power of the sun and fossil fuels. The power of fusion has the potential to change all of this. However, over ages and ages and ages, fusion of water will deplete rivers and eventually even oceans. With access to Europa, Ganymede, Pluto, and eventually the gas giants, this loss of hydrogen is offset, and, at least theoretically, for ages upon ages to come.

-Reassurance of the survival of humanity and other species.
Of course we are all programmed with the need to procreate. So why not spread to other planets to minimize the risk to our species as a whole? Populating multiple planets and moons decreases the probability that humanity would be wiped out entirely, or set back to the stone age by a single mega-disaster.
Quantum_Conundrum
A Brief Synopsis of Mining operations on Europa

Everything here is techically and theoretically "doable" right now, with the exception of the Fusion reactor.

The biggest problem on Europa is the cryogenic surface temperature. Initially, the problem is not so much in keeping people warm once you have a sealed environment. No, the problem is that most metals become brittle at these ultra low temperatures. i.e. ~50 - 125 Kelvin. By comparison, Mars is 186-268 Kelvin, which makes Mars a cake walk. This isn't a problem, because mining operations on Europa would not reallly be needed for perhaps several centuries after a Mars colony is founded (depending on exactly how much water and oxygen are available on Mars.)

For Europa, in theory, once you have a nuclear reactor running (whether fission or fusion), you can generate quite easily enough heat to pump through the substructure of the buildings to prevent the metals from becoming brittle. Simply pump heated water directly through the foundation and walls of the structure, keeping the metals at human friendly temperatures. To prevent most heat from escaping (except when you want/need heat to escape,) the surface of all the external metalic foundations, walls, and ceilings are covered inside and out with insulating tiles. Thus metals for strength and durability, insulating tiles to protect the metals.

Components for all the structures: reactors and processing plants, living quarters, farms, waste management, etc, and the mining facilities are constructed on Mars and/or Luna from materials mined from Mars and/or Luna, and transported to the site on Europa. Thus, the first few weeks through the first few years of the initial operations on Europa would be incredibly difficult by comparison to most things we are familliar with, but by then humanity will likely have discovered the best metals and meta-materials to use for all of this. Essentially, everything, including the nuclear reactors, needs to be pre-fabricated on Mars or Luna, and then set down on the surface of Europa in the largest possible sections, then quickly assembled. Heat is provided initially by hydrogen fuel cells.

A small Fission reactor is installed initially for the primary purpose of jump starting the Fusion reactor, and providing all the power the colony needs in and of itself for perhaps even the first few years or decades. After the fusion reactor is online and stable, the Fission reactor can basicly be set to its minimal power output unless it is needed again for some reason.

A meltdown of the Fission reactor is of little consequence, because the worst case scenario is that it simply melts through the crust of the moon and lands on the bottom of the ocean, 100km below, where it would be out of sight and out of mind for many, many millenia. By the time our decendants mined that far down so that it would be a concern, they would surely have discovered means to deal with it.

Use of giant ROVs (Remote Operated Vehicles) will be crucial to positon each section of the colony's structures where they need to be, especially up until the colony is fully self sustaining. The ROVs are constructed in much the same manner: Metal and perhaps polymer indostructure coated in insulators, kept warm by electrical and fluid heating mechanisms (from burning H2 + O2, and eventually from the fission and fusion reactors). These function much like an electric weed eater, with large power line running directly to the Fission power plant, and later, directly to the Fusion power plant. Most of the operations will be taking place within a kilometer or so of the core of the colony, so direct electrical cable is far more efficient when possible as compared to fuel cells. The cables must also be contained in an insulated pipe which has warm air pumped through it to avoid cryogenic breaking.

Europa is gravitationally locked to Jupiter, nevertheless, at least in theory, the dead poles of the moon should be the safest, most stable place to build the mining colonies. Eventually, they would want six mining colonies on Europa: one at each pole, and 4 equidistantly around the equator. This way the water-ice is mined approximately equally from all directions on the surface. This minimizes the risk of artificially caused ice quakes as time goes on.

Each colony is designed modularly in such a way that they mostly propagate out radially from the center, except with openings where mining vehicles need to come in and out for maintenance, with airlocks between each module.

In the event of a fire in any module on Europa it is handled like so: Humans evacuate the module if necessary. Next, the air locks are sealed, and a combination of compressed helium and CO2 is sprayed into the room. The Helium is much lighter than oxygen and is totally inert, thus it floats to the ceiling and extinguishes any fires that are trying to burn across the ceiling. The CO2 is much heavier than O2, and so sinks to the floor, extinguishing any fires that are trying to burn across the floor. Once the fire is extinguished, air compressors simply suck the gases back up and store them in compressed form again. This same system can be used even more effectively on Mars, where CO2 in the atmosphere is abundant and can be compressed just as easily as any air compressor on earth. Because of the way the modules are designed, nothing more than superficial damage could ever be done by a fire anyway. It may burn things like clothing, furniture, carpet, or blankets, but not much of anything else, and certainly not with this system in place.
Cusa
I don't think having many people in space is practical. The best shot is the moon but even that looks incredibly impractical to me.
Quantum_Conundrum
QUOTE (Cusa+Dec 14 2008, 05:49 PM)
I don't think having many people in space is practical. The best shot is the moon but even that looks incredibly impractical to me.

Sailing around the world in a wooden boat was impractical in 1492.
Cusa
It's just my opinion. NASA's record should tell you how dangerous what you're posing is. Maybe in a million years but what problem will it solve?

Certainly not overpopulation.

Mitch Raemsch
Quantum_Conundrum
QUOTE (Cusa+Dec 14 2008, 06:56 PM)
It's just my opinion. NASA's record should tell you how dangerous what you're posing is. Maybe in a million years but what problem will it solve?

Certainly not overpopulation.

Mitch Raemsch

It doesn't solve overpopulation, this I admit.

Unless we had fusion power as a means to achieve the energy necessary to recycle chemicals for rocket fuel, and literally shipped half the earth population to outter space, and even that would only decrease "overpopulation" by about 72 years worth of growth...



Ok, so it doesn't solve overpopulation.


But what it DOES solve is this problem:

"Gee wiz! Look at that big space rock headed to us. Looks like our entire species is going the way of the dinsoaur!" or the Dodo, take your pick.
Cusa
Probes to watch for asteroids and comets throughout the solar system would do the job; something like Star Wars would take them out.

Mitch Raemsch
philip347

I am for the allowance of building spaceports right away.
I am also for the allowance of building more advanced spaceships, than we are currently allowed to build now.

The reasons for my prompting this move, is both the ice age that the Pentagon said that we're in and a certain level of evolution that comes along with these ice ages.

To be exact, the predicament that we're in is so dangerous, that this would be similar to having a girlfriend of a wife who could turn into a werewolf.

The only thing is, that her ability to morph into a dangerous animal, is not based on lunar pull cycles, but per chance happenstance.

This would be like one second she was normal, then the next trying to claw and get at you.

sources, movie media The Day After Tomorrow, as this is a true and accurate source, of how drastic the climate and weather can change overnight.
Capracus
QUOTE (Quantum_Conundrum+Dec 11 2008, 06:38 AM)
Europa: The Key to colonizing Mars, Neptune and Uranus.


Cusa
We just got off the launch pad. Space travel can weight. It should if it is to be done right. Look at NASA.

I wonder what science will be like in a million years.

Mitch Raemsch
Capracus
QUOTE (Quantum_Conundrum+Dec 13 2008, 03:43 AM)
But what does Earth gain?

-Knowledge.
Increased total human population increases the probability of discovering new technologies which can benefit earth throughout the millenia, even if there never is a net "material" benefit. But there will be a net material benefit, as I will discuss.
If you're going to depend on human intelligence for technical innovation, then you need to maximize human potential. This can be done conservatively through selective breeding and strict social engineering, or more intensively through genetic and technological modification of the human form. Simply cranking out greater numbers in the hope of hitting an occasional intellectual jackpot is an unproductive gamble.

As far as the interplanetary engineering, it makes more sense to adapt humanity to survive and cope with the challenges of extra terrestrial environments, than to change those environments to suit a functionally limited human form.

QUOTE
-Water and hydrogen.
Eventually, barring some world war or mega-disaster, human civilization on earth will grow beyond the capacity of the earth's biosphere to support merely on the power of the sun and fossil fuels. The power of fusion has the potential to change all of this. However, over ages and ages and ages, fusion of water will deplete rivers and eventually even oceans. With access to Europa, Ganymede, Pluto, and eventually the gas giants, this loss of hydrogen is offset, and, at least theoretically, for ages upon ages to come.
There is no reason that the Earth need be consumed or environmentally spoiled by the excesses of humanity. Humans in their present form can adopt a lifestyle that is more compatible with the needs of the natural systems of the planet, and still reach their limited intellectual and technological potential. The task of space exploration should be left to their more advanced progeny.

QUOTE (->
QUOTE
-Water and hydrogen.
Eventually, barring some world war or mega-disaster, human civilization on earth will grow beyond the capacity of the earth's biosphere to support merely on the power of the sun and fossil fuels. The power of fusion has the potential to change all of this. However, over ages and ages and ages, fusion of water will deplete rivers and eventually even oceans. With access to Europa, Ganymede, Pluto, and eventually the gas giants, this loss of hydrogen is offset, and, at least theoretically, for ages upon ages to come.
There is no reason that the Earth need be consumed or environmentally spoiled by the excesses of humanity. Humans in their present form can adopt a lifestyle that is more compatible with the needs of the natural systems of the planet, and still reach their limited intellectual and technological potential. The task of space exploration should be left to their more advanced progeny.

-Reassurance of the survival of humanity and other species.
Of course we are all programmed with the need to procreate. So why not spread to other planets to minimize the risk to our species as a whole? Populating multiple planets and moons decreases the probability that humanity would be wiped out entirely, or set back to the stone age by a single mega-disaster.
The present inhabitants of the Earth would be better served by a planetary environment that maintains an equatable balance of natural diversity and human development. This means that humanity would have to limit its population to optimal numbers. With our more advanced progeny inhabiting the environs of space, their superior insight and technology would be insurance against disaster from within or without. They essentially become our caretakers, our gods.
IAMoraes
(QC, I have immensely enjoyed this thread.

I have been unable to write a worthy comment yet, but it is an incredible thread!) wink.gif
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