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There are some big problems with your design. Two of them are that your balloon is going to poduce less lift and thrust as you get higher and without lots of extra fuel will produce no thrust and regardless of fuel no lift. You have to make quite a high speed to acheive the hights your talking about and your spacecraft will produce thrust only for the first few miles in addition your ballon's mass to drag ratio will be enormus. Starting higher (as a baloon lets you) decreases the possible thrust of an air breathing system by allowing it less time in thicker air unless the lift is high and allows it to gain a lot of speed from it. In short it will need a lot of kinks worked out and a lot of redisign (I can think of a lot of other problems) but some vaugly similar design may one day fly, although I doubt to space but at least in the atmosphere. If you think you can make it work, persue it.
I think the best way for mars and space exploration in general to be pushed in the united states is a rally in the capitol demanding funding for missions now. This shows politicians how many people REALLY care about a cause and are willing to seriously support it and put tons of effort into it. I am not talking small isolated marches by space advocacy organizations, those make the cause look weak. We need one huge rally with people from any and all space organizations in the U.S. The Planetary Society, The Mars Society, The NSS, and others will need to start a massive recruitment and publicity campaign inlist the support of the media and of celebrities. The groups need to unite all their manpower and a lot of their resources to support pro space candidates and gain political support and visibility. Then, during a presidential campain, hold a massive support program for the space supporting candidate. Do the utmost to get the candidate elected (as well as congressional candidates). Regardless of the outcome (up to a point) hold a massive rally and public sace fair in washington during the budget deliberations and get a lot of money and commitment pumped into a long term space exploration and colinization program. Money will not likely be a problem because the aerospace industry stands to make a fortune if the program succedes and could be induced to support it rather easily with financial contributions. If more celebrities and media personalities can be made to support space exploration it could inlist huge pulic support. Lance Bass' possible flight could begin a trend that should be taken advantage of. If enough active as well as passive support can be raised then we can make it work, it will require 10s or even 100s of thousands of active supporters and millions of passive ones. If space activists settle their differences and move together it can probobly be done.
I don't favor american emperialism over any other method myself. I would not be in favor of restricting immigration to americans even in such a case as an american empire. I am for space colonies however they come however. Waiting for an international group to do it when the U.S. could do it faster is not my cup of tea. I think all methods should be persued and the one giving the most progress for the shortest time, assuming we could get funding, should be chosen. American, and other nations, imperialism could be the quickest way to space as it inspires copetition and government funding. China's upcoming manned launch might spawn the american (that is my) government into space big time, it will almost certainly result in some funding increase. It could also get europe to create a manned launch program uping the number of nations or groups of nations capable of putting a man in space with things built only within those nations to four. The Russian Federation, The United States, and hopefully within the next decade The Peoples Republic of China, and Europe (I beleive the european space agency is not affiliated with the european union.)
I agree that the air breathing engine as a first stage is great idea. There is actually no statement as to whether this configuration will take off horizontally or on a runway. The horizontal option improves preformance dramatically. Versitility of launch site is not so important at this point, and there will be plenty of options even for a horizontal take-off vehichle. This method and I beleive all the methods make the landing site very versitile, this is a bit more important as far as safety and flexibility than the launch site being flexible. It is said somewhere on the Space Launch Initiative homepage that designs for horizontal and verticle takeoff craft are in the works. I wouldn't rule out a craft that can be launched either horizontally or vertically interchangeably. This would allow for maximum versitility for small payloads and resque/crew delivery missions while allowing for the sheer lifting power needed for large payloads.
I agree. Such a study is planned by the mars society. They plan to put a satilite creating artificial gravity through centrifigal force with mice on it in orbit. The mice will then be returned after a significant stay at mars g. I beleive that they are considering flying this mission either independantly or aboard the ISS. A stay in orbitwould be about forty days. Some mice would be born and grow to udulthood at mars g. This should provide much needed data. If aboard the space station I beleive that the centrifuge could be reused allowing several generations of mice or several different studies perhaps involving other levels of force (such as lunar) or other animals such as reptiles or even fish and anphibians. Quite a scientifically worth while experiment.
six months each way is more fuel effecient. Actually I beleive it is the most fuel effecient route to mars (and back) in a reasonable time frame. Thus it would be cheapest to use a six month time period.
How will low gravity affect people visiting lower surface gravity planets, such as on an extended mission to mars (1-2 1/2 earth years), people born on earth but living for a long time on a lower gravity planet, and people born on a low gravity planet. Microgravity is known to cause muscles and bones to weaken significantly thus rendering astronauts having spent months in space temporary invalids upon there return to earth. I beleive it takes at least few days for them to recover much significant mobility and possibly weeks or more. There are apparently some long term affects as well including permanently reduced bone density. The bodies natural healing methods are detrimentally affected by microgravity. A cut dosn't heal in space. How would martian or lunar gravity affect the bodies regeneration and immune systems. Would a Martian or lunar born person be able to take a visit to earth. I think it would be very difficult and likely dangerous for a martian and and life threatning for a lunar person.
This topic was suggested by Adrian in the topic Mars Mission. Step 1. There is some extensive discussion of it there. Anyone who posted about this elsewhere feel free to copy your arguments/comments over here.
I would like it if I could have the chance ot only to go to mars but see people living there and participate in that process. When I am getting old I want to see maturing colonies off of earth not brand new ones. The mars society is trying to jump some of the cheaper and more time consuming technological burdens now so that a future mission will take less time to develop. Sad that so few are doing much of anything. Perhaps China's entrance onto the manned space seen will spur space development in other countries (espeially the U.S.) including a mars mission. It is expected that China will launch the first flight of its relativly ambitios space program next year. They plan to put up a space station and send manned missions to the moon and (eventually) mars.
It would have to extend a good deal furthur than the larange point because the centrifigal force exerted by the rotation of the cable needs to balance the total pull of the moons gravity on it. At the larange point a satilite would be gravitationally balanced however only a small part of the cable will actually be at the balance point the rest is sunk deeper and deeper in the moons gravity well. An attached cable thus needs to be very long, however an unattached cable in relative motion to the lunar surface could actually be quite a bit shorter reducing the amount of materials needed to build it. Also it has the benifit of allowing a circle around the moon access to the cable rather than just one settlement. The only reason a similar idea wouldn't work on earth or mars is that the cable would be moving faster than the atmosphere and friction with it would slow it down. A huge quantity of thrust of some type would be needed to hold the cable up, this kind of defies the whole purpose of the thing.
It is hard to feed a rocket powder however many liquid fuels are used as hydrogen substitutes. Also you don't need to convert the fuel to hydrogen, you just find one which reacts completely with the oxidizer and use that, it is more efficient. However if you meant making the powder into hydrogen and feeding the hydrogen into the engine this requires a lot of extra weight. There is no reason you couldn't dissolve the fuel in water at as much fuel to water as possibe and feed that into the engine letting it react with the oxidizer.
Also flourine is a much better oxidizer than oxygen in terms of preformance and the fact it is non cryogenic (you don't have to super cool it to make it liquid). The problem with flourine is it is toxic when in pure elemental form, while the rocket exaust wouldn't necisarily be toxic if the rocket exploded or crashed it could spread a toxic gas, not good. (flourine is the most reactive element)
Another thing you want is a light fuel (better preformance, lower weight) at least in general. So using lithium or another light element in place of sodium is more effecient. I think you are on the right track thinking about new fuels and propulsion methods. As far as chemical rockets go I favor flourine hydrogen or a similar high preformance fuel. Flourine and methane or kerosine will also work I beleive. Kerosine would allow greater fuel density and all the fuels involed would be liquid at room temperature simplifying things greatly in many ways.
I think this would take a long time and not provide much extra thrust. However I beleive it is basically the same as a gravitational assist which allows you somewhat more bang for your propellant buck. Gravitational assists work better when coming from outside the planets gravitational domain and when the planet is larger (like Jupiter). A gravitational assist with jupiter was used on all the outer planet probes I believe (the voyagers and the pioneers). It is also worth more if you are going a longer distance as a slight increase in velocity subtracts more time from a longer trip then a shorter one.
The Mars Society is sending up a satilite which will test this very affect on mice sent into space. They will use a centrifuge to simulate martian gravity, in this case it will have almost exactly the same affect force wise as actually being on mars. Mice will be sent up and mice will develope and be born on the satilite. I beleive it will be in orbit for 40 days or so. The animals will then be brough back to earth for further study. This should resolve exactly what variations in gravity will do to natives of other planets. There is a report on it a little ways down the front page of The Mars Society website.
I don't think there is any dispute that you would at least need to be excellent physical shape to do anything on earth when coming from mars because you you will have to exert more energy to walk around etc. due to you increased weight. It is an interesting topic.
I totally agree. I think the most important source of contamination we have to worry about on such missions is earth microbes getting to mars or into our sample. Earth bacteria (if they somehow survived) could compete with martian life some looooooooooong way down the road and hurt the natural enviornment. That seems about as likely as the earth being contaminated by martian microbes. The biggest reason to carefully handle a sample return mission is to prevent our samples getting contaminated by earth microbes. Contamination would greatly reduce the sample' s scientific value.
Actually I said that you should use an earth based microwave transmitter for atmospheric ascent (taking a few minutes) and once in space deploy solar panels for power.
A mission isn't possible within the current world production having to use chemical power for all power the entire time. You would literally need millions of tons of fuel. You have to use solar or nuclear (fusion or fission) power somewhere along the line or you have to carry chemical fuel for heating/cooling, other life support, cooking, communication, lighting. You name it it uses power. Not only that but you must launch shield and store the fuel increasing the amount of fuel needed. The mission blows way out of proportion.
Also currently no viable electric power generation system exists based on fusion (other than using fusion produced sunlight). However fission reactors work quite well and would be perfect for a mars mission.
A lunar elevator attached to the moons surface would have to be very long due to the extremely slow rotation of the moon. Interference form earths gravity in addition to the hugely greater cost of such a long cable probobly makes it infeasable. However there is talk of a cable which orbits the moon with the cable bottom close to its surface so that a veihicle could latch on to the bottom of it and climb up. This would move relativly quickly over the lunar surface but is more feasible than an ultra long cable. There is some pretty good discussion of the various ideas in entering space (for instance a carousel type arrangement). There is no reason a non attached elevator can't work, it would require heavy supervision and often need slight adjustments but would likely work quite well.
Note as Shaun said your body will be used to mars or lunar gravity if you are born there (possibly even if you live there for a while). Your muscles and bones won't be strong enough to support your weight on earth if you were born on mars or the moon. If you never work out you can't just go pick up 1 or 2 times your own weight. If you are from the moon you would have to carry six times your normal weight. I weigh about 150 pounds in normal earth gravity. If gravity were to multiply by the same amount for me as it would for someone visiting earth from the moon I would weigh 900 pounds. I would be not to happy and it would be a health risk. The Earth exerts 6 times as much gravity on its surface as the moon exerts on its surface and 2.5 times as much as mars on its surface. Mars to earth might be safe, maybe, moon to earth would be a major health hazard. This dosn't even mention the additional force exerted when taking off from earth. At three lunar Gs I would weigh 18 times my normal weight. Humans in centrifuges have endured this for short periods of time but the average person might not be able to take the immense force.
A rotating hub with a fusion engine which is smaller and produces less thrust allowing for less fuel and a longer trip might work. You don't have to use the max speed of your propulsion system, it is often more effecient if you don't, double the payload and halve the speed for any given acceleration device.
In most cases refusal to publish is the sign of a deluded crank. They are many in number, many of them are destroyed by revealing the basic method of their system. I read one apparently well designed website made by someone who truly believes that hydrogen will split and become monoatomic in the presence of a catalyst releasing gobs of energy. Basic knowledge of chemistry shows that this isn't possible. It would be nice if one of these people with extravagent claims were right but all told most of them are just crazies.
Plasma rockets are fuel efficient, however you must add to the wieght of every bit of fuel they use (such as xenon) the weight of the chemical fuel needed to accelerate it. Fuel cells produce energy maybe a bit more effeciently than a rocket engine but power is also lost in moving it around. Anyway it is certainly better to beam power via mirowaves to an ascending plasma rocket rather than degrade its preformance with heavy chemical fuels. I beleive that there has actually been a satilite power beaming system emplaced at some point, power via satilite from alaska to africa or something. It is inefficient for power transmission on earths surface it is cheaper to just build a straight power line or move the fuel, it is very effecient for a rocket however because of the immense cost of lugging fuel. Once in space a plasma rocket could be solar powered thus eliminating the need for chemical fuel. If your going to build a plasma rocket chemical power generating fuel on a large scale is not worth your while, as it removes one of the best feature of the system, the low fuel requirement.
Actually many different outlines have been suggested and are widely known. I recommend going to your local library or book store and picking up and reading the case for mars by robert zubrin. This is a fin and informative book and if we can get familliar with what is in it allows us to debate the questions it poses and think of new things rather than rehashing the same stuff over and over. That is not a good way to make progress. It would be nice if doctor Zubrin would post his book on theinternet for all to read, It would probobly up the readership dramatically and increase support for missions. Unfortunately this would probobly cause him to lose a good deal of money, maybe he could think of it as a contribution to the cause. Anyway most people recommend sending a series of missions culminating in an outpost manned for 2 years out of every two and a half years. From there a permanently manned outpost could be established and transition into a colony as well as allow colonies to develope on other areas of the planet. We need to know a good deal more about mars and have some more practical experience with utilizing its resources before we go on to full fledged colony. However I beleive that if NASA or some other organization or group of organizations buckles down to it now we could have a colony established by 2030 if not sooner. Unfortunately no one with significant resources seems to be really ready to commit to men on mars. Till then those of us who dream of mars must do what we can and press slowly on toward men on mars.
By the way I think that the size of a genetically self sufficient colony needs to be about 300 unrelated individuals and that is the bare minimum. However they would likely start a colony small with few people (ten or so maybe more or less) and fill it up with new immigrants at an ever increasing rate. This allows for experience to be gained with risk to fewer people and for an infrastructure to be developed so that many esentials such as habitats don't have to be brought from earth. This dramatically decreases the cost of getting more people and increases the number that can be sent over by allowing them to bring less. There is also tak of sending sperm and eggs over and using them for artificial insemination to increase the genetic diversity of the group. Sperm and eggs getting sent over is much less costly then sending over additional people and while the children produced must be carried and raised you can bring several hundred times the genes with the same weight as a person. Some people even talk about an all female colony which would allow the maximum child carrying and thus grwth ability for the colony with the least weight. This seems a little drastic but is an interesting idea.
A chemical power supply is capable of producing more output per wieght over a very short period of time than a nuclear poerplant. However you have to run a plasma rocket for the whole trip not just the beggining. Chemical power is not a good method of powering a plasma rocket, you will get more power using a cemical rocket engine. The most effecient chemical power options currently in use are hydrogen oxygen fuel cells, beleive me a hydrogen oxygen rocket engine is going to produce a #### of a lot more thrust than running a plasma engine off of fuel cell power.
A solar thermal rocket is a viable alternative to nuclear, chemical, or plasma engines. Basicaly it uses large reflectors to heat a fuel and spew it out the back. It could use any number of liquid or gaseous fuels the best being hydrogen. It could also be refueled with carbon dioxide ( or any other available liquid or gas) which you can pull right out of the martian air. The biggest problems would be folding and unfolding the reflectors (if you want maximum efficiency) and getting all that carbon dioxide to the viehicle (you would need a larger return rocket to get the fuel to the ship)
Solar sails also show much promise as a propulsion metod. (again much of the problem is in getting it unfolded without ripping the huge sail)
Exactly. If they could get some pop culture figures interested in mars and space exploration in general that could start quite a popular space movement. Perhaps if Lance Bass (n-sync guy) gets the fall soyuz seat to the ISS it will get such a movement started. It will be really great if he gats a lot of publicity and tells his fans how much space exploration means to him etc. I don't enjoy pop culture very much but by definition it gets people wild about things, people are voters, and politicans are gonna do what the voters want. Also with popular support it would be much easier to drum up money for private space exploration.
When I said survivor style, I meant a reality TV series. Obviously it is completely ridiculous to vote people off part way through. I intended to show a way such a mission could be made into entertainment rather than just news. It would have to be piched right but there is no reason I can see that people wouldn't watch a half hour of the highlights of a mars crew's day every day. If it was pitched right and properly made it could be as popular as many TV shows that draw consistent viewing for years.
I imagine coverage of a mars mission in a Survivor like fashion could produce a good deal of money, two and a half years of non stop usually interesting programming. I don't like the idea of a corporate mars mission (seems like prostitution) and the government would not sell rights to it. The US government dosn't sell exclusive ad rights to fund its projects. A private venture capitol style corporation along with the use of exclusive ad rights and the offer of a substantial prize could get people to mars much more effectivly (in my opinion). You could also use company specific talents to help support your mission. Food companies could use their developement departments to provide food for the mission, a car company could develope the rover for the mission. This could be carried all the way from their seats and beds to their medical supplies etc. Could save a load of money.
The current space station design was actually chosen specifically to utilize the space shuttle. (According to Entering Space by Robert Zubrin) The space station was originally an American project and was later expanded to become multi national. The way it works now is you assemble it in space from pieces. However it is much cheaper to design a heavy lift booster and boost a station into orbit all in one piece. The reason they chose not to do this was to increase the number of space shuttle launches, which would decrease the cost of the shuttle per launch to about the same price as a standard non reusable rocket. They chose to stick with this design when the US station project became the international space station to allow each nation to build a part and to preserve the origonal design. The main purpose of this design (substantially increased space shuttle use) however was gone. It would have been more economical to launch the ISS in one or two pieces on a russian enirgia booster or two. Building the whole structure on the ground internationally is cheaper than assembling peices in space. At least according to Dr. Zubrin. It makes a good deal of sense. I suggest that you buy or take a look at Entering Space, it is very well done and informative. (Especially the first two thirds or so.)