Lots of talk lately concerning the moon

oscarb44 · Aug 12, 2004

/* off-topic post deleted */

orzek · Aug 12, 2004

That is a great post kadetken. Looks like mental doesn't have a response to it.

orzek · Aug 12, 2004

larper says: The energy required to send 1 kilogram to the Moon is about the same as to send the same kilogram to Mars. Quite correct. I’ll see if I have the stats somewhere, they were posted on the “Lets Design a Mission To Mars thread that was deleted. I would still like the numbers for why it is the same. Though if the trip is one way then yes the fuel requirements go down quite a lot. But the first missions to mars will not be one way. Who knows when the missions will change to just dropping off passengers for colonization.

larper · Aug 12, 2004

I think the main reason that the delta v for Mars is about the same as the Moon is that you can do aerobraking/capture at Mars and not on the Moon. <div class="Discussion_UserSignature"> Vote Libertarian </div>

larper · Aug 12, 2004

My reasons for Moon First are several. Mental_Avenger, wvbraun, and I have stated our positions several times in older threads. I'll state them one more time for the newbies here... The technical issues with Mars First vs Moon First are not really the point, in my opinion. We can argue the tech and the cost and the delta v all we want. The biggest issue, however, is psychological. To have a major Mars/Moon initiative, we have to have general public support. Not minimal public support, but general public support. That means that people will want to be able to realize the benefits of the program, or at least believe that they COULD realize the benefits of the program if they wanted to. (Kind of like the right to own a gun. I don't own a gun, but I know that I could own a gun if I wanted to.) Any way you cut it, a trip to Mars is going to be long, dangerous (or perceived as such), and possibly uncomfortable. Furthermore, if a Mars trip is one way, people are going to be a lot less inclined to go. And if they don't feel like they could ever go, they aren't going to support paying taxes just so other people can go. Even colonists, firmly believing that they are going to Mars to stay, will feel a lot of trepidation about the fact that they can never return "home", nor even ever see "home" again except as a bright star in the morning sky. Now, colonists on the Moon face a completely different psychological situation. They can see home. The trip out is not very dangerous. It is uncomfortable, but they can stand the cramped quarters for 3 days. And even though they have commited to staying on the Moon, the possibility of returning to Earth is much more real. They will feel a lot more at ease with their decision. The folks on Earth, meanwhile, can see the Moon. Most do not know how to find Mars in the sky. Seeing the Moon, they will start to realize that there are people there, living, working, buildin <div class="Discussion_UserSignature"> Vote Libertarian </div>

orzek · Aug 12, 2004

That is true. But the atmosphere around mars is a lot thinner and therefore you need higher precision than is needed to aerobrake with the earth. But yes if you are able to aerobrake reliably then the costs do drop. I wonder if anyone can give figures for the various delta v's concerning mars and the moon.

orzek · Aug 12, 2004

larper said:My reasons for Moon First are several. Mental_Avenger, wvbraun, and I have stated our positions several times in older threads. I'll state them one more time for the newbies here....... Larper, those are pretty much my views why we should go to the moon first but also because of the potential resources that the moon could provide.

mental_avenger · Aug 12, 2004

orzek claims: That is a great post kadetken. Looks like mental doesn't have a response to it. You are wrong, orzek. Again. Note the time, it was 5:30 in the morning here and I had been up all night. I really didn’t have the ambition to respond to what amounts to unsupportable opinions based on guesses, conjecture, and supposition about how the general population “might” react at some undefined point in the future based on conditions that may or may not be relevant at the time. More later. <div class="Discussion_UserSignature"> Our Solar System must be passing through a Non Sequitur area of space. </div>

orzek · Aug 12, 2004

You are wrong, orzek. Again. Note the time, it was 5:30 in the morning here and I had been up all night. I really didn’t have the ambition to respond to what amounts to unsupportable opinions based on guesses, conjecture, and supposition about how the general population “might” react at some undefined point in the future based on conditions that may or may not be relevant at the time. More later. Boy that sounds like sour grapes! In terms of "unsupportable opinions based on guesses, conjecture and supposition" that can easily be applied to most of what YOU have been saying all along! A lot of what kadetken said is quite valid and I don't see why you would have a problem with it.

scottb50 · Aug 13, 2004

"Bentonite, Trona, Coal, Shale, and Shale Oil, Natural Gas, Uranium, Copper, Gold, and Sulfur." Pretty much everything that the Moon doesn't have. If we want to use rocks then the Moon might be a good place to import them from. It would also be great if we could mine the Moon and not tear up the Earth, true, but the composition of the Moon holds few minerals that it would be worthwhile going after, Silca is pretty abundant here. One thing to keep in mind is the average density of the Earth is 5515kg/m3, the Moon is 3350kg/m3 and Mars is 3933/m3. Neither hold out much prospects for commercially valuable material. To consider going to the Moon a way to stop the ravishing of the Earth is also rediculous. More to the point is we have barely scratched the surface of the Earth, the fact we haven't left it better than, or at least as good as we found it is the problem. There is no excuse for destroying the land to get minerals, just as there is no excuse for destroying the land and forests to feed people. Maybe if some of the money went to reforestation and correcting the problems and less went to huge mansions, G-5's and golden parachutes we would be better served. To think we can solve our problems on Earth by plundering another world is no different than the Spanish in the Americas. At least we don't seem to have any natives to subdue. <div class="Discussion_UserSignature"> </div>

mental_avenger · Aug 13, 2004

kadetken, Let me start off by saying, that although I do not agree with everything you say, you do make some good points. I agree that the Moon has more sunlight than Mars. However, unless you limit yourself to the poles, that 14 day blackout can ear your lunch. The disparity between the ideal mining sites and the idea solar sites will cost a great deal in transmission lines. (especially if you have to lift all that wire from Earth to the Moon to start your operations.) From what I have read, attempting to process regolith, while easy to gather, may yield relatively low percentages of the material we would need. The regolith covers so much of the surface of the Moon that there is no way to know what is underneath all that dust. In addition, since concentrated quantities of useful materials are likely the result of a comet or asteroid strike, a great deal of core-drilling survey will need to be done to locate profitable mining sites. IOW, we won’t be able to set down anywhere and begin processing. kadetken says: The purity of the materials processed can be superior to anything we could spend the electricity to produce here on Earth. Modern technological processes require a high degree of purity (I'm just trying to picture the ash that would go into creating carbon for carbon-fiber), and the Moon delivers, especially at the poles. I understand the purity requirements. Could you expand on your comment about the poles “delivering”? kadetken says: As halman noted: "Creating growth in the economy means finding new sources of raw materials, new methods of processing them, and new markets for the finished goods. Although you do not specify, it appears that you are advocating supplying Earth with materials mined on the Moon. I apologize if I mistake your meaning, but, even given all the problems with finding and processing <div class="Discussion_UserSignature"> Our Solar System must be passing through a Non Sequitur area of space. </div>

mental_avenger · Aug 13, 2004

Boy that sounds like sour grapes! How motivated would you be at 5:30am after no sleep? A lot of what kadetken said is quite valid and I don't see why you would have a problem with it. “Valid” in this case is only a matter of opinion, not fact. Since the entire issue is predicated upon what people who are not born yet might or might not do in a situation which we are not qualified to predict, the issue at this point is all conjecture. As we have seen, conditions and popular attitudes change quickly and dramatically, sometimes pivoting on what some would consider trivial events. <div class="Discussion_UserSignature"> Our Solar System must be passing through a Non Sequitur area of space. </div>

mental_avenger · Aug 13, 2004

kadetken: You may be casually indifferent to inflicting that sort of thing on the rest of the world (re: the previous 8000 dia. ball of resources comment), but the rest of the world may or may not be quite so receptive. The local conditions are a result of rather unrestrained mining operations during the last 100 years. Nowadays, a lot more care is taken in preserving the ecology of the region. In some cases, the ecology actually benefits overall from the process. It all (currently) depends more on local politics and power than it does on the law. kadetken: We're actually at a unique point where the environmental movement can be swayed to support space development by virtue of the fact that by moving resource processing off planet Once again it sounds like you believe that we will be able to import raw materials from the Moon. Please show me the figures that would make this viable within the next 200 years. Shoe me the numbers. IMO, that is the pipe dream upon which all other pipe dreams are judged. kadetken: We know what's on our Moon. It's not conjecture or speculation. Not really. As noted earlier, the concentrations of certain materials will probably be from comet and asteroid impact, and are likely to be buried or scattered. The fact is, that we know very little about the actual makeup of the Moon other than the apparent lack of certain necessary elements such as carbon and nitrogen, without which a self-sufficient colony cannot be established. Looking at your list, did you notice a conspicuous lack of the “C” word(carbon )and the “N” word?(nitrogen ) <div class="Discussion_UserSignature"> Our Solar System must be passing through a Non Sequitur area of space. </div>

mental_avenger · Aug 13, 2004

kadetken: Well, the hydrocarbons will hopefully come from the asteroids, I hear that old saw about getting materials from the asteroids so often it is becoming a cliché, but I have yet to hear a single viable and workable plan to do so. Usually, its something like, “we just go out and push one into Earth orbit,” or “Oh, when the time comes we will have the technology”. Reality check. Mining asteroids in place would be prohibitively expensive and time consuming, and attempting to move them towards the Earth will not only be prohibitively difficult, but the governments of Earth would never allow it, regardless of how many assurances were made. Face it, it ain’t gonna happen. kadetken: From my post we have the following elements represented - H, He, C, N, O, F, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Y, Zr, Nb, Ru, Rh, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, Os, Ir, Pt, Pb, Th, & U. Unless I missed something, there was only a miniscule amount of Carbon (tied up in cementite) and no nitrogen in your list. The current estimated makeup of lunar crust is: Oxygen 43% Silicon 21% Aluminium 10% Calcium 9% Iron 9% Magnesium 5% Titanium 2% Nickel 0.6% Sodium 0.3% Chromium 0.2% Potassium 0.1% Manganese 0.1% Sulfur 0.1% Phosphorus 500 ppm Carbon 100 ppm Nitrogen 100 ppm Hydrogen 50 ppm Helium 20 ppm kadetken: Surely not all of these are useless. There's actually enough "bio" elements in a cubic meter of regolith (mostly SWIEs) to make two ham sandwiches, apples, and sodas. Wrong. Without the carbon and nitrogen, you cannot make a ham sandwich, nor can you grow food for you hungry workers, nor can you supply a breathable atmosphere. BTW, the entire fi <div class="Discussion_UserSignature"> Our Solar System must be passing through a Non Sequitur area of space. </div>

mental_avenger · Aug 13, 2004

BTW, I didn’t see He, N, V, Nb, Ru, Rh, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ta, Os, Ir, or Pt represented in your post. Since the abundance of materials was your main point, would you mind pointing out those elements in you post, and their relative amounts? Thanks. <div class="Discussion_UserSignature"> Our Solar System must be passing through a Non Sequitur area of space. </div>

najab · Aug 13, 2004

Importing raw materials from the Moon is very easy. Throw them. Orbital mechanics and the properties of regular bodies entering the atmosphere are both very well understood, impact points can be fairly precisely predicted. Lauch from the Moon with a linear accelerator, three days later collect materials from the hole in the desert.Finished goods might be a little bit trickier....

mrmorris · Aug 13, 2004

"three days later collect materials from the hole in the desert." I've also read articles on the possibility of forming the raw materials into hollow spheres or honeycomb construction which would increase the displacement enough to allow for an ocean impact and recovery.

halman · Aug 14, 2004

RadarRedux, In your post of 08/09, you lament that NASA so far has only revealed plans for a small number of people to be on the Moon for a short period of time. I cannot see how we can expect anything more without a greater financial commitment. The Apollo program received the equivilant of about 4 percent of the federal budget for several years. Even with the proposed increases in spending, NASA funding over the next 15 years is still going to amount to less than 1 percent of the federal budget. If we can not convince Congress to get serious about space exploration, and begin funding it at least at a level of 1 percent of the budget, we are very likely to see no manned missions ANYWHERE! Somehow, we have got to convince people who believe that living and working in space is really science fiction that we can actually do it! Too many congressional representatives think that spaceflight is 'scientific research', which has no immediate usefulness, and will not have any usefullness in the forseeable future. These people believe that Earth is the only place that is real, that people can live and work. Finding arguments which will persuade people to support spaceflight is the single most critical thing which anyone who believes that there is good to come from getting off of this planet can do. I have long believed that spaceflight will provide the solutions to many of our problems, because so many of our problems stem from pretending that there is no other place than Earth. We act like we live in a closed system, but it is closed only because we are still realizing that there is something beyond the atmosphere. The vast majority of people on this planet have no idea that there are other worlds in space. Many Americans have no idea that there are other worlds in space. We must find a way to show everyone that this is not the only place that there is. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

halman · Aug 14, 2004

Mental_Avenger, I apologize if you got the impression that I have advocated importing raw materials from the Moon. I would never consider such lunacy! When I speak of creating new markets, new products, I am speaking in regards to processed materials and finished goods. Mines on the Moon will be of little value unless the materials they yeild can be used in space, or processed in space into goods which cannot be manufactured economically on Earth. This will require factories in orbit, where raw aluminium can be melted, purified, foamed, and annealed. Frame members for spacecraft, airplanes, automobiles, and bicycles are all potential products. When one considers the price of a set of titanium golf clubs, or a titanium bicycle frame, such markets do exist. Another factor is the cost of energy use. Energy is becoming more and more expensive, and the cost of librating energy is getting more and more expensive also. If all steel made on planet Earth had to be produced without environmental impact, steel made in space will probably be competitive, if not cheaper. Environmental costs are a major reason why many American firms have moved operations off-shore. What will happen when there are no more countries willing to sacrfice their environment for rapid economic growth? You say that you are afraid of a world-wide plague caused by an engineered virus. I'll see your plague, and raise you five degrees Celsius worldwide. We don't have to wait for some lovesick teenager with a flair for bio-chemistry to destroy the world, we are already hard at work doing it. Raising the standard of living for everyone on this planet to the one that we enjoy seems like a worthy goal, until we factor in the environmental costs. But it does not have to be that way. The Earth is not a closed system. We can make the things that we want and need elsewhere, and then bring them here. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

orzek · Aug 14, 2004

Thankyou a lot kadetken for those delta-V figures and the reference.

arobie · Aug 14, 2004

And for all the information about mining, materials that would come from it, ways to go about it, and space infrastucture. It is all very fascinating. Thank You.

spacester · Aug 15, 2004

Mp = mass of payload, kg Can be found from Mp = 2 * eta * rho * C * G * H / dV^2 eta = efficiency rho = 1900 kg / m^3 http://fti.neep.wisc.edu/neep602/lecture15.html C = Volume of regolith, m^3 G = 9.81m/s^2 * 0.167 = 1.638 m/s^2 H = Height above ground, meters dV = deltaV to LLO with eta = 0.85 C = 1E4 m^3 H = 20 m dV = 1870 m/s Mp = 2 * 0.85 * 190 * 10000 * 1.638 * 20 / 1870^2 = 340 * 1900* 1.638 / 18.70^2 = kg/m^3 * m^3 * m/s^2 * m / (m^2 / s^2) = kg Mp = mass of payload = 3025 kg 3.33 tons could be lunar orbited using a volume of lunar regolith 50 m x 50 m x 4 m dropping 20 m with 85% efficiency when converting the potential energy to orbital energy. KE = ½ Mp V^2 = ½ * 3025 kg * (1870 m/s)^2 = 5.29E9 N *m = 5.29E9 J Three hours spent in raising the weight = 10800 sec Power = energy / time Power = 5.29E9 J / 10800 sec = 4.898E5 watts = 489 kilowatts (edit: 489 kilowatts = 656 horsepower ) <div class="Discussion_UserSignature"> </div>

orzek · Aug 15, 2004

For mars the delta-v's taken from "Expedition Mars" by Martin J. L. Turner ISBN: 1-85233-735-4 are Using 500 km low earth orbit as starting point Velocity of Circular orbit around earth = 7.62km/s LEO to Earth-Mars Transfer orbit = 3.55km/s Earth-Mars transfer orbit = 2.94km/s Earths orbital velocity = 29.8km/s Using Hohmann Orbit. Near Mars: Mars Orbital velocity = 24.14km/s Spacecraft at aphelion = 21.47km/s To enter Mars orbit at 500 km = 2.52km/s Orbit around Mars velocity = 3.31km/s Landing on Mars = 3.42km/s Total delta-V required by spacecraft to get to Mars= 9.49km/s A Return Journey requires around 19km/s all together. Of Course with aerobraking and aerocapture one can remove quite a lot of velocity though the martian atmosphere is overall thinner but at higher altitudes it is actually denser than the earths atmosphere. Some rocket power will be needed for a more precise landing. Aerocapture is possible but difficult because the 'window' of altitude is only a few kilometres wide.

radarredux · Aug 15, 2004

> In your post of 08/09, you lament that NASA so far has only revealed plans for a small number of people to be on the Moon for a short period of time. I cannot see how we can expect anything more without a greater financial commitment./i> Hi Halman, While NASA’s budget today is smaller as a percentage of the federal budget and GDP than it was during the Apollo program, don’t forget that both the budget and economy have grown faster than inflation during the last 40+ years. Thus, the cost NASA is projecting to put a man on the Moon by 2020 is virtually identical, when adjusted for inflation, to the cost of putting a man on the Moon in 1969. Remember, when Kennedy proposed the goal in 1961 there was virtually no NASA infrastructure – all of this (which exists today) had to be built up during the Apollo era. We had not even put a man in orbit. We had virtually no knowledge, experience, or technology to operate for more than a few minutes in space. America’s manned space exploration program only had the achievements that Burt Rutan has today. Everything had to be invented from scratch. Also during the last 40 years America’s economy has experienced tremendous growth in productivity. Tied to this, and of particular interest to space exploration, is the development of high-speed computers and networks, computer aided design and manufacturing (CAD/CAM), computational fluid dynamics (CFD), and virtual collaborative work environments. Furthermore, there have been great gains in material science, especially with respect to strong but lightweight composite materials. Given today that we have so much infrastructure, we have four decades of gained knowledge, experience, and development of space technology, and we have had productivity gains and other technology developments like computer workstations, why is NASA saying it will cost just as much today to put a man on the Moon as it

orzek · Aug 15, 2004

I have noticed that nearly everything, not just space programs are more expensive than before even with inflation taken in account. It is curious that with todays technology going back to the moon is that expensive, I wonder for how much the russians would be able to do it for?

Lots of talk lately concerning the moon

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