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Thread: Idea for space elevator and ship.

  1. #1 Idea for space elevator and ship. 
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    My idea for a space elevator would be a magnetic rail up into the sky held up by helium blimps high in the sky as close to space as possible. The rail propels the space craft up shortening the fuel needed to blast off into space. The space crafts can be small, like satellite small, if needed this way. The rail itself may be able to throw the space craft into space itself if the craft is a space blimp filled with helium. Maybe there will be enough inertia. Then the ship can move around by fuel and reenter the same way with a heavy gas.


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  3. #2 Space Elevator Impossible 
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    The space elevator is a beautiful concept for space travel. It first was proposed many many years ago.

    Helium close to space is an issue - it needs to float in air and as the air thins there are issues as to its celing height.

    The original concept was for an actual space elevator with a space ship sitting in space, tethered to the ground. But until recently the materials needed to create the tether would have been so heavy the tether would have come to ground under its own weight.

    If you look at the X Prize Foundation - they actually had a prize for people who could propel a wieght up a tether only 10 metres from the ground with no onboard fuel. I don't think anyone won that prize because it was too problematic. Imagine sending something up hundreds of kilometres using microwaves or the like.

    The biggest problem with the space elevator is that the geosynchonous orbit location for Earth is 36,000 kilometres from the Earth's surface. Anything else circling at the speed Earth is turning would come crashing back to Earth because it would be so slow as to not be able to counter Earth's gravity. Now as soon as you add even one kilogram to the space ship at 36000 k's from earth's surface - but back at Earth's surface you will be pulling the space ship back to earth - the extra weight will be adding to Earth's gravitational effect. So the space ship would have to accelerate to counter that and would therefore no longer be in geosynch with earth. So it would have to be located many many more k's from earth. Imagine the tether - say 100,000 k's long - that would be interesting.


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  4. #3 the SpaceShaft a different type of space elevator 
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    The idea is not that crazy, it is just a matter of finding the solutions. What is needed is to find a way to solve the major problem concerning the lack of buoyancy in Space. The other problems are not beyond the limits of our human technology, as is with the length and strength of CNT tether/cable.

    The solution is to generate upthrust beyond the heights where the atmosphere is still dense but without the use of rockets. Let me further explain.

    We know that buoyancy is not the same as upthrust, (yes I know that upthrust should be splitted into two words but I prefer to make use of them as one for the theory I am presenting).

    The difference between buoyancy and upthrust is explained by the fact that one is an effect and the other is a result. Buoyancy is an effect that happens when a body lighter than the medium in which it resides moves in an upwards direction and at some future time a state of equilibrium is reached, i.e. the object will at some point then come to a state of rest. During the ascension time, the forces that propelled the buoy upwards will:

    1) Decrease overtime, mainly due to decrease of the density of the medium, and
    2) are not cumulative, since the object further dissipates the collected energy with the environment with which it interacts, e.g. by friction.

    On the other hand upthrust is a process by which energy is collected overtime. E.g.; a rocket gets charged with the energy it develops during it ascent until all the fuel has been burned. The resultant of the process of burning the fuel is, beside the displacement up to a chosen elevation, the inertial factor by which it will remain aloft, as for a short time, to then maneuver and engage its second stage as to then work in gaining escape velocity tangentially, (i.e.; horizontally and not vertically relative to the planet's surface). Further explaining the flight mechanics of a rocket is here unnecessary, but the point is that of exemplifying the process by which a certain amount of energy was collected and saved during the ascent time and then dispensed for some other task, which is other than the ascension, to initiate the tasks nevesary to stay at an altitude due to the tangential velocity.

    The question that follows is how "to save" the gravitational energy that could be gathered during the ascent of a buoyant object.

    Let us now look at an object that is commonly found within the maritime industry, namely a spar-buoy. A spar-buoy is an elongated buoy which is used among others to indicate the tide level. Such a buoy is anchored to the bottom of the waterway and has approximately half of its body submerged while the other half extends vertically above the water surface. The higher the tide the greater the force the underwater section will collect. Let us now, metaphorically speaking, correlate:

    1) The fluidic environments of a body of water with that of the atmosphere, and
    2) the atmosphere with that of Space.

    If a large structure could be built and made to behave as a spar-buoy, with its extending length equal or larger than the distance equivalent to that which defines the atmosphere as the region in which the laws of aerodynamics are still applicable, we could theoretically have a "super-carrier space elevator" and not just a flimsy cable. Half of the object will be below a waterline elevation while the other will be floating above, (or into Space).

    Furthermore, let us now imagine a hydraulic jack. Such a device will extend upwards due to the gas pressure being concentrated within its internal chamber. Besides the potential energy, the more gas the higher the telescopic system will extend. Let us now marry this description to that of the spar-buoy. If a method could be devised to increase (or decrease) "at will" the system upthrust, from the base of the spar-buoy while slack is given to the anchor-line of the super spar-buoy; the top section will be displaced by any desired measure above the imaginary waterline, i.e. any altitude could be achieved into Space.

    Such a super spar-buoy device goes by the name of a SpaceShaft and it aims to harness the infinite gravitational acceleration that our planet has to provide for the upthrust of a unidirectional elevator system.

    Other points I would like to stress here are:
    * We are aware that for a SpaceShaft to function, other systems such as anchoring and mooring will need to be implemented. However these are by far easier to device than a CNT tether.
    * That the SpaceShaft is not meant to dismiss the qualities of the CNT tether system but to complement it.
    * Another reason that must be taken into account that is to encourage further study of a SpaceShaft is that; if for whatever reason a CNT tether space elevator could not be constructed a SpaceShaft could be our "Plan B".

    For more info visit http://spaceshaft.org

    Bye for now.
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  5. #4  
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    Your ideas are interesting. However, wouldn't the big issue be the speed needed to stay in space for the craft versus the speed that the Earth is turning.

    I acknowledge the concept that there is outward force being applied - however that will involve ongoing energy to be applied which means storing energy for such a force. The idea of the space elevator originally was to employ geosynchronous orbit - hence my earlier observations.

    But it is still worth contemplating.

    I just have issues with its stability as a concept - even if stable for one configuration - tethered - would immediately become unstable as soon as a weight is applied - so the intent of the system is impossible which is a pretty fundamental problem.
    I am a believer in a simple universe governed by simple rules, with only one force influencing all matter. I believe gravity is a result, not a force and I would like to progressively attempt to find alternative explanations for strange events/activities starting with Dark Matter.
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  6. #5  
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    Thank you for your comments.

    Your first question regarding the necessary velocity to keep a satellite aloft in orbit a.k.a. escape velocity is by no means something unusual. Every launched rocket has to use a first stage to bring up other sections to a specific altitude from which the task of achieving escape velocity is to be initiated by means of the 2nd stage. Typically, the 1st stage has a vertical trajectory in which an enormous amount of energy is used not so much as to achieve a final velocity but to provide enough inertia as to keep the remaining sections in a "negative freefall" condition long enough as to maneuver the remaining of vehicle into a suitable orientation and then fire the 2nd stage rocket. The actual velocities a 1st stage rocket is able to achieve is never, i.e. absolutely never, close to match-1, and is most likely to be in the region between 60 to 200 mph. Escape velocity is actually a combination of the actual velocity the 2nd stage can add-up to the "free-ride velocity" that our planet's rotation naturally injects.

    Not any space elevator can produce any propulsion for any vehicle to travel to its final destination that is even if a satellite is brought at whatever altitude, including GEO, it will still require its own propulsion systems to move away from the launching-deck. And such a deck would have to be at GEO for a launching system to exist as to allow the craft to move free and away from the space elevator. So this feature must be part of the CNT Tether SE as it will also be needed for its deployment as it will be discussed later.

    Dreaming that in a near future a CNT Tether SE would be constructed is no solution to our current problems. Consider all the challenges that such a system has:

    * The need of long and reliable CNT strands, without mentioning an actual rope.
    * Then; the relocation of an asteroid or the construction of a station at GEO. Which, even if a cable is to be deployed bidirectionally, and would theoretically make the station redundant, something will still need to be up there as to function as a deployment base for the tether and other tasks including the mating of the new rope sections.
    * Then you have to bring up into Space all the necessary spools. Consider all the financial problems NASA and especially the private sector has to live with. Do you really think that there is any money to be made from Space, such that the private sector will run to invest into the possible business?
    * Then you have all the perils, from debris to atmospheric deterioration of the material. How are we to maintain such a system with the unlikely infrastructure such tasks will require?

    I can go on and on, but it is obvious that a CNT Tether SE is not to happen in the next 10 years as promised neither; 20 or 30. I will acknowledge that work on the materials will bring many spin-offs but all the ideas that are so much cherished by the public already have patented beneficiaries among the games organizers and other 3rd parties. So even if a CNT Tether SE is never built they would have benefited from cheap labor provided by every one that picks up the challenge.

    In a nutshell, which system is truly the most unrealistic? A SpaceShaft will keep the rocket industry in business, while deployment systems will need to be manned and so with maintenance teams. Architects would be needed as also many other professionals therefore generating a viable business. One which may be more expensive than the $100 a ticket being promised but it will be there in a much shorter time if it is really what people want.

    Me too I am a believer of a simple universe but I don't believe in fairy tales, therefore I came up with a more realistic system. I certainly don't have all the answers, since aerospace is not my domain, neither am I a distinguished researcher or writer with great oratory skills, but the figures show that a SpaceShaft is perfectly achievable. If you add to this the expert work of professionals in the field of aerospace, architecture, materials engineers, etc. they all can bring the different solutions needed.
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    Just one other conundrum in relation to the space elevator. Assume we can solve the issue of balance so that either the space elevator doesn't come plummeting to Earth as soon as you put any significant load on it from Earth, and it doesn't pul the core off the surface by its tension if the centrifical force is too great, what happens when the load passes into space?

    In an elevator you simply pass the load out of the elevator. And you walk off on the path or floor in a building, but if you take a load up to say 500kms, the apparent weight of that load is going to be 86% of what it was on Earth less a little bit for the centrifical force of the speed based on Earth's rotation. As soon as the load comes off the elevator it is going to want to come quickly back to Earth, unless you can get it up to about 35,000kms/hr pretty quickly. Now that is going to take some propulsion - not sure where the energy for that is going to come from.

    I still have reservations about the stability of the space elevator concept. It is not just being sceptical, it is based on the relative balance of the system at different distances from Earth. It is just not in balance which leads to instability.

    By the way - the comment about simple universe was in my setuip - I didn't put it as a comment for your topic - but thanks for your comments about it.
    I am a believer in a simple universe governed by simple rules, with only one force influencing all matter. I believe gravity is a result, not a force and I would like to progressively attempt to find alternative explanations for strange events/activities starting with Dark Matter.
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  8. #7  
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    Quote Originally Posted by RichardL
    Just one other conundrum in relation to the space elevator. Assume we can solve the issue of balance so that either the space elevator doesn't come plummeting to Earth as soon as you put any significant load on it from Earth, and it doesn't pul the core off the surface by its tension if the centrifical force is too great...
    The strain that's added to the cable when you add some cargo to be hauled up will be pretty trivial compared to the strain that the cable is already under from its own weight. The center of mass would be slightly past the point of geostationary orbit, which is why the "anchor satellite" wouldn't get pulled down as soon as you add a little more weight (cargo).
    As soon as the load comes off the elevator it is going to want to come quickly back to Earth, unless you can get it up to about 35,000kms/hr pretty quickly. Now that is going to take some propulsion - not sure where the energy for that is going to come from.
    The "top" of the elevator is in a stable geostationary orbit. When you step off the top, you too will be in a stable geostationary orbit. Falling back to Earth would only be a problem if you get off the elevator before reaching the top. The energy needed for the "horizontal" acceleration comes from the Earth's rotation. When you add mass to the cable near the bottom and start to send it up, conservation of momentum causes the cable to begin to lag behind the Earth's rotation. But the end of the cable is attached to the Earth, and the Earth isn't going to slow its rotation (at least, not much!) so the cable is pulled "forward" and back into position as the elevator car rises, which also adds horizontal velocity to the car as it ascends. The physics of the rotating Earth/cable/anchor satellite cause the cable's position to be self-correcting when it drifts out of position. The entire space elevator is basically a machine for stealing some of the Earth's rotational energy and transferring it to your cargo so that your cargo gets up to orbital speed.

    Edit: Also, you'll only be going about 11,000 km/hour. 35,000 km/sec if for a low Earth orbit. The space elevator will put you in a geostationary orbit.
    I still have reservations about the stability of the space elevator concept. It is not just being sceptical, it is based on the relative balance of the system at different distances from Earth. It is just not in balance which leads to instability.
    I don't understand what you mean here. What specifically isn't "in balance"?
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  9. #8  
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    My point is that the top of the elevator is going to have to be at least 100,000km's from Earth to maintain tension on the elevator tether to make up for the weight of the tether itself - and the potential for added weight in thr form of the load applied when something is being elevated. The geosynchronous orbit will only be achieved if the "load" is desptached from the elevator at 36,000 km's but does that mean we are assuming each load will be travelling 36,000 km's on the elevator before leaving. Any other option would mean force would be required to achieve orbit or in fact leaving orbit. That seems a long way to have to send loads before despatch each time - but it could be done I guess.

    My issue with lack of balance is that the weight of the tether and load at Earth's surface is going to be very much the same as any other mass because the Earth's rotation at low altitudes will not provide any more lift than it does sitting on Earth just because it is part of the tether. It is only after 36,000 kms that the Earthbound pull will become zero and after that negative. This means the tensions on the tether and the entire system in fact will be different at different parts of the tether. There is no other conclusion one can come too. Whether this is stable or not is a matter of one's perspective I guess.
    I am a believer in a simple universe governed by simple rules, with only one force influencing all matter. I believe gravity is a result, not a force and I would like to progressively attempt to find alternative explanations for strange events/activities starting with Dark Matter.
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  10. #9  
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    Hello again,

    Have anyone consider what would be Plan B if a space elevator is not feasible?
    No I am not trying to trash the system and all the work done by several of the researchers.

    I have met with several of them and discussed both theirs and my approach. (FYI they consider the SpaceShaft approach as not inline with the rules of the SE games, one of the reasons why my group does not participate at the yearly competitions.)

    And one of the conclusions that many of them have is that even if the SE is never built the research done will still be worthwhile since it would have been at the source of other developments, especially in the field of nanotubes.

    However, again the question is what is Plan B? I.e.: If we really want to have economical access to Space?

    I wanted to give an extended reply to the previous questions but I feel compelled to write this quick comment.

    We humans are very good at building structures, ever since before Stonehenge to the towers of Eiffel to those in Dubai and those to come. A SpaceShaft is nothing but a tower that is being built from the bottom upwards thanks to buoyancy, with guy-cables pretty much like an antennae, it is perhaps slow in achieving orbital altitudes but an internal shuttle will do the trick of fast travel. There are no major problems with debris and security since it does not have to reach GEO and if a catastrophe happens it is a buoyant system that will not fall back to Earth, and as a plus it will be by far easier to reattach. It would encourage developments of not only CNT but other technologies including those of rocketry, etc.

    And I could go on an on.

    The question should perhaps be instead why is this system unattractive?

    http://spaceshaft.org
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  11. #10  
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    Quote Originally Posted by RichardL
    My point is that the top of the elevator is going to have to be at least 100,000km's from Earth to maintain tension on the elevator tether to make up for the weight of the tether itself - and the potential for added weight in thr form of the load applied when something is being elevated.
    No, it won't. You just have to keep the center of mass of the entire system (cable+elevator cargo+anchor satellite) past the point of geostationary orbit. How far the end of the elevator is from the Earth's surface will mainly depend on the mass of the anchor satellite; the more massive it is, the closer to geostationary orbit it can be.
    The geosynchronous orbit will only be achieved if the "load" is desptached from the elevator at 36,000 km's but does that mean we are assuming each load will be travelling 36,000 km's on the elevator before leaving. Any other option would mean force would be required to achieve orbit or in fact leaving orbit. That seems a long way to have to send loads before despatch each time - but it could be done I guess.
    Yes, it is assumed that any load to leave the elevator will be getting off at least 36,000 km up, unless the cargo either has a rocket attached or is planning to fall back to Earth.
    My issue with lack of balance is that the weight of the tether and load at Earth's surface is going to be very much the same as any other mass because the Earth's rotation at low altitudes will not provide any more lift than it does sitting on Earth just because it is part of the tether. It is only after 36,000 kms that the Earthbound pull will become zero and after that negative. This means the tensions on the tether and the entire system in fact will be different at different parts of the tether. There is no other conclusion one can come too. Whether this is stable or not is a matter of one's perspective I guess.
    Yes, the tether will be under increasing strain as you move closer to the the anchor satellite. But then, this is true of any cable hanging under gravity, whether it reaches orbit or not. The cable simply has to be strong enough to not snap, even close to 36000 km where the strain is very very high. I'm not sure why this sounds "unstable" to you.
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  12. #11  
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    Quote Originally Posted by seminone
    Hello again,

    Have anyone consider what would be Plan B if a space elevator is not feasible?
    No I am not trying to trash the system and all the work done by several of the researchers.

    I have met with several of them and discussed both theirs and my approach. (FYI they consider the SpaceShaft approach as not inline with the rules of the SE games, one of the reasons why my group does not participate at the yearly competitions.)

    And one of the conclusions that many of them have is that even if the SE is never built the research done will still be worthwhile since it would have been at the source of other developments, especially in the field of nanotubes.
    Yeah. Nanotubes are pretty impressive. I'm sure the funding has at least a dual purpose. The space elevator concept is probably just a way of capturing peoples' imaginations.



    However, again the question is what is Plan B? I.e.: If we really want to

    We humans are very good at building structures, ever since before Stonehenge to the towers of Eiffel to those in Dubai and those to come. A SpaceShaft is nothing but a tower that is being built from the bottom upwards thanks to buoyancy, with guy-cables pretty much like an antennae, it is perhaps slow in achieving orbital altitudes but an internal shuttle will do the trick of fast travel. There are no major problems with debris and security since it does not have to reach GEO and if a catastrophe happens it is a buoyant system that will not fall back to Earth, and as a plus it will be by far easier to reattach. It would encourage developments of not only CNT but other technologies including those of rocketry, etc.
    You're talking about the OP's concept, right?

    I'm wondering if we could create a yoyo/swinging rope type effect with a nanofiber cable, where a high flying aircraft sort of sling shots objects into space by swinging them on long strands of nano-fiber rope. It wouldn't work for putting humans into space because the accelerations would be too high (and humans can't survive more than about 4 G's), but I wonder if it might work as a means to throw some fuel packets into orbit, that can later be retrieved by a space shuttle or something, and used to extend its range.

    I'm thinking that, if your fuel is already up there, then you don't need to worry about bringing it with you.
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  13. #12  
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    No OP's concept or yoyo/swinging rope. It is a method of constructing something that can be compared to a building of over 60 miles by using the atmospheric pressure of our planet. Although it will require especially strong materials it will not require something like CNT. I don't want to rewrite again stuff that is written somewhere else but I am happy to respond to some other questions like; where would the necessary helium come from? Or how to calculate the upthrust? etc.

    visit http://spaceshaft.org
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  14. #13  
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    Quote Originally Posted by seminone
    No OP's concept or yoyo/swinging rope. It is a method of constructing something that can be compared to a building of over 60 miles by using the atmospheric pressure of our planet. Although it will require especially strong materials it will not require something like CNT. I don't want to rewrite again stuff that is written somewhere else but I am happy to respond to some other questions like; where would the necessary helium come from? Or how to calculate the upthrust? etc.

    visit http://spaceshaft.org
    It looks like the top of it is 100 km high. How does the payload get the rest of the way up, and how does it achieve orbital speeds?
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  15. #14  
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    What mechanism does it use to climb the string? I think a lot depends on the mechanism. If it just winds up a mechanical spool or wheel type device to get to the top, then it won't be able to achieve very high speeds before reaching the top.

    If it uses some kind of magnetic means of accelerating off of the string, then maybe it could get going really fast. (I don't know though.... would the string be magnetically reactive, or magnetically inert?)
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  16. #15  
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    The summit being at 100 km is not the maximum altitude that the hydraulic mechanism could support. I will clarify why this is in a moment but let me first point out that this elevation has been proposed only as a reference for those that may look at atmospheric applications such as; greenhouse gas sequestration or perhaps a system to route space produced energy down to sea-level that could finance the endeavor.

    Let me stress that this system is not a tower but something of a hydraulic system. The calculations that I have shared elsewhere have been done based solely on the atmospheric environment and with specific dimensional characteristics. Namely those of a structure with a central column of a diameter of 100 meters, which will provide an approximate concentrated upthrust of 5000 tonnes at its summit, or if you prefer distributed throughout the non-dense regions of the atmosphere where the structure is under a condition of pure weight.

    There are two solutions to increasing either upthrust or altitude:
    . 1; increase the diameter of the structure
    . 2; start deployment from a lower elevation than the radius of our planet.
    . Which implies deployment of the sectional rings of the structure below a
    . mass of water such as an artificial basin, lake or ocean. This of course will
    . increase the upthrust 1000 fold due to the fact that water is about 1000
    . times denser than air.

    There are other mechanisms to achieve the same result. However, they depart from the original idea so I will not discuss them.

    Another important aspect of why build only up to 100 km is because it could be done with materials widely used in the aeronautical industry and not as imperatively more sophisticated as those used in the space industry. Notably I will point out to the fact that at altitudes of 100 km plastic composites can still be used because temperatures are still within the limiting material specifications. If we were to go further up we will need composites that are ceramic based or metallic because temperatures get above 100 centigrade (or 300 Kelvin or 210 Fahrenheit).

    Regarding the second question, concerning a propulsion system of a shuttle which travels through the flue of the shaft.

    I believe the next explanation is already described in more detail at my website/blog but in a nutshell assume that it will be a combined system involving buoyancy and electromechanical systems. For example: Using a vertically oriented airship capable of reaching altitudes above 30 km, (and hopefully up to 50 km,) providing the upthrust and afterwards solely by the traction of an integrated vertically climbing/crawling mechanism.

    Not discussing in more detail other possibilities is a conscious decision I have made. However, although I may have worked out some systems and the loads they will have to endure I would like to delegate some stuff to others, mainly because the endeavor is at this time still 100% theoretical and I can use some ideas from others. Moreover, without any funding other than my own pocket I cannot get too far. Recall that other endeavors such as those like the ISEC, SpaceX, etc. are made up by many brilliant minds that do attract investors and not just from an apparent loner and dreamer like myself.

    Anyhow I will be posting on my blog some calculations on a PDF format, hopefully in January of next year after the EuroSpaceward conference, until then please forgive me for not doing it right now.
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