Talk:Why Moderate Sized Rockets Are Better

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Revision as of 17:09, 12 May 2009 by Farred (talk | contribs) (touch up)
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I have referred to my concept of Lunar development as "reasonable" in the article, and as "rational" in other places. This means little without the basis for deciding what is reasonable. I take profitability as my basis for deciding. By investment standards profit from Luna is so risky and removed into the future as to make money spent on development no investment at all. The same standards can be used to evaluate development decisions regardless. One merely imagines a very low rate of return for an investment that does not mature for a very long time and is very risky, and then does the best possible within those limitations. One plans for various contingencies. Every thing I know about lunar development indicates to me that if people follow through persistently the environvent of lunar investments will change in the distant (perhaps fifty years) future. There will be a high rate of return and secure knowledge of performance. Making decissions based on profitability leaves some chance of failure; but the Apollo on steroids strategy leaves little chance for success unless your goal is leaving a few footprints on Mars and proving once and for all time that space exploration is just too expensive to have any practical benefits.--Farred 17:31, 26 March 2009 (UTC)

  • Why did I call investment on Luna "risky" if everything I know points to future high returns on investment? Does not long time to maturity cover the entire set of adverse conditions? It is not what I know that indicates risk in lunar investments. It is my ignorance. The total of human knowledge about Luna is much greater than my own, but the total of human ignorance about Luna, as a fraction of my own ignorance, approaches unity. So there is a vast area out of which the risk of failure arises. Also, there is no guarantee that the individual person, corporation or nation that invests in lunar development will reap the profit. There is no guarantee that others will follow through with investments made today to the point that a profit is ever achieved.
  • Those who care for nothing but the amount left in their retirement accounts at death, those who feel faint at the thought of risk and those who think humanity utterly incapable of sustained efforts of more than twenty years should have nothing to do with lunar investment. Those who think that the spark that caused man to irrigate the Babylonian empire and build cathedrals is still operating and still admirable should consider the effort of lunar development worthy of itself whether they can live to taste the fruit or not.--Farred 15:29, 28 March 2009 (UTC)

I had a feeling an article like this would be created at one point. I won't comment on the "launcher size argument", but I have a problem with asking for the cancellation of the Ares V. The Ares program has it's own problems, most not attributable to launcher size. Ares I has become a big problem, not Ares V. Constellation might just cancel itself- it certainly does not need a bunch of space advocates to worry about it. Also, one must not regard NASA as our only path back to the Moon...

T.Neo 18:33, 30 March 2009 (UTC)

  • Who should invest in lunar development? Individuals, organizations, corporations, and governments who have resources that they can afford to loose and who want to help create a prosperous and secure future for humanity. It is not yet time to get shares in development corporations that might in the future be worth enormous sums to your heirs. Governments will get around to laying the international legal groundwork for such corporations eventually. Perhaps without any delay to development work caused by waiting for such legal groundwork. More knowledge is needed about just how lunar development might proceed so negotiators know something about what they are negotiating. Governments will also want to assure the ability to inspect lunar developments to insure that they are militarily harmless.
  • Why should we invest in lunar development? It has been mentioned elsewhere that lunar materials could be used for space based solar power and orbiting space ports. Besides this a space based civilization could possibly avoid disaster by climate change of the run away greenhouse or run away ice age types that have been suggested by various sources. (Which of these catastrophes Earth's chaotic climate will throw at us is still in doubt, and may depend upon what we do on Earth.) Just as industrial capabilities of some nations on Earth have doubled and doubled again within the last couple of millennia, capabilities of a space based civilization would be expected to double repeatedly, with a much higher upper limit to the possible capabilities to be attained. Shading Earth from the sun as it starts to enter its red giant phase and even moving Earth farther from the sun are well within the capabilities that could be attained. Man will never attain any of the grand capabilities without taking the first step of industrializing either Luna or Mars. The second step will get us the pair.
  • Unfortunately avoiding the possibility of military self destruction will not be available for quite some time (not until people build colony ships to send to other stars). As people gain more space based capabilities, we will realize new and more powerful ways to kill ourselves. We will simply need to continue to talk to each other and convince ourselves not to kill each other.--Farred 16:11, 4 April 2009 (UTC)
  • What sort of efforts should be made to develop the resources of Luna, Mars and Ceres? Here are several points to consider.
  • First we must recognize that the chief economic advantage of these places is the potential for cheap transportation of either raw materials or processed products into orbit.
  • From Luna only about 0.4 kilowatt-hours of energy must be transferred to a kilogram payload to put it into orbit. If the over-all power efficiency of an electric launching system is 40% then it would use one kilowatt hour per kilogram of cargo launched into orbit. At current earthly rates for electrical power that would be less than a nickel a pound. What the cost of a kilowatt of power on Luna will be is subject to change, but the potential for low cost shipment of cargo to orbit is there if a large scale market is developed. Allowances for interest on the capital investment and maintenance also are less per pound if there is a large scale market for launch services. The situation is considerably different from that on Earth where the savings from increasing the size of the market are limited from the inefficiencies of scale that hinder the launch market on Earth, such as the increasing cost of liquid oxygen and land area for launching pads as these items become more expensive when demand goes beyond a certain amount.
  • Mars also has large unused resources which could be pressed into service to launch cargo to orbit. Luna could benefit from receiving hydrogen, nitrogen, carbon, and argon from Mars and pay for it with money from the sale of raw and processed materials to orbiting factories. A single stage to orbit fully reusable space craft is much easier to design for Mars than for earth.
  • From Ceres about a fortieth of a kilowatt-hour is sufficient to launch a kilogram of cargo to orbit. Launch system efficiencies should be high because a simple merry-go-round could accept cargo near the center without stopping and drop it into orbit at the rim. Two cargoes launched tangentially to the surface at escape velocity in opposite directions to balance the launcher would end up going in almost the same direction. They could rendezvous with each other with a reasonable amount of maneuvering fuel. If it is preferred to have a station in synchronous orbit about Ceres as a depot, cargo could go up and down a 426 kilometer long cable between the depot and Ceres. The cable could continue to 663 kilometers above the equator of Ceres where it is possible to simply drop cargo into an escape from Ceres trajectory. This would be a possible place to anchor the tensile load of the cable with the lower end anchored on Ceres. The depot at 426 kilometers would remain attached to the cable but have very nearly zero net force transferred between the depot and the cable. Cargo containers could be gathered at the depot and loaded on an interplanetary tug which could dock weightlessly at the depot. Such a tug might use partially ionized oxygen gas as reaction mass of a VASIMR rocket.
  • Second, any human presence will require a massive industrial establishment to support it from local materials. Having many people to operate such a system would be counter productive, because then it would be necessary to have more machinery to support these workers. Automatically functioning redundant machinery for life support is therefore necessary for economic use of these places. The priority in developing a space based economy is not having people in orbit supported by Earth based supply but developing automatic machinery that can operate by remote control.
  • Third, Luna is the closest source of materials that could potentially be launched into orbit at a cost of less than a dollar a pound. It has a round trip communications delay of less than three seconds, which is suitable for some sorts of remote control that are not practical for Mars.
  • Fourth, there are many special conditions at Luna, at Mars, and at Ceres that provide a special advantage or require special efforts to accommodate. For example, the low light intensity a Ceres could be countered by ultra light weight mirrors bent into a parabolic trough shape in weightlessness to concentrate light either on solar cells or on the hot end of a heat engine.
  • From all of these considerations it seems that the most important thing to be done now for developing a space faring civilization is learning all the details which determine how much it costs to start taking advantage of the opportunities offered by places like Luna, Mars and Ceres. Various plans for using these resources in complimenting each other should be considered and evaluated in light of the details of the physical condition of these resources. When the best plans that will actually turn a profit are discovered, the legal framework for investing in earnest should be available.
  • Of all the robot spacecraft, rovers and automatic experiment packages that could be launched to learn what we need to know to develop a space based economy, none needs to be launched on a Saturn V class launcher. Since it is necessary to develop remote controlled industry including remote controlled manipulators to get a space based economy started, any large platform needed in space should be assembled from pieces that can be launched on moderate sized launchers, which are cheaper per pound than the Saturn V class launchers. Assembling large platforms from smaller pieces is practice for the automated and remote controlled work that will be necessary for economic development of extraterrestrial resources.
  • A fully completed International Space Station (ISS) may not be the most economical resource possible for doing experiments in space, but we are committed to supporting it for a while. Research done at the fully completed ISS to support automated space manufacturing could be helpful. When the time for which we are committed to supporting the ISS is expired, there should be a hiatus in the manned space flight program. This should continue until the unmanned efforts have developed resources to the point that people can be supported cheaply enough on local resources and there are sufficient resources in space for people to do things that make economic sense.
  • The hundreds of times reductions in the cost of lifting stuff to orbit that NASA has sought will not happen before there is development of infrastructure in space, because all schemes for reducing the cost of lifting stuff to orbit by such a factor are dependent upon a high volume of traffic that can not be sustained without the development of the infrastructure necessary to make it profitable. Do the exploration and development work with light weight long endurance robots first and high volume reductions in the cost of getting to orbit will follow. The long reign of NASA's wishful thinking based launch system development plans should be at an end.--Farred 03:52, 11 May 2009 (UTC)