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Benford on Space Exploration
gid-goo writes "Gregory Benford looks at what we should do in the aftermath of the Columbia accident. Is the shuttle, or the International Space Station for that matter, useful? Or just payola to aerospace interests and a means for keeping Russian rocket scientists employed?" Benford's comments about the necessity of a closed biosphere and of some way for astronauts to stop muscle and bone loss are far more insightful than the usual discussions about where our space exploration priorities should lie.
http://www.ananova.com/news/story/sm_246696.html Scientists say they've discovered that cats purr to help them get better when they're injured. The researchers at the Fauna Communications Research Institute in North Carolina call the purr a natural healing mechanism. They say the purr helps their bones and organs to heal and grow. It works in a similar way to ultrasound on humans. Exposure to similar sound frequencies are known to improve bone density. Dr Elizabeth von Muggenthaler, the president of the institute, said: "Old wives' tales usually have a grain of truth behind them and cats do heal very quickly. The healing power of purring seems to explain their 'nine lives'." She told The Sunday Telegraph: "We are starting to solve a 3,000-year-old mystery as to why cats purr. The next phase will be to explain the mechanics of the process." Story filed: 15:49 Sunday 18th March 2001
That reminds me of an old Popular Mechanics I found asking the question "should we be going to the moon?" There were lots of "fix things on earth before going to space" arguments...but, what if we tried that? Would things be better on earth? Don't we all benifit from the technology developed during the space race? There will always be homeless...there will always be poor. If we wait to fix every problem we will never make progress.
It's tragic to watch the current fallout of the Columbia disaster. Certainly NASA, relevant manufacturers, and the United States Government will be asked to answer for any negligence which may have caused the loss of the shuttle and her seven crew. But I would implore anyone reading this not to conclude that the loss of the Columbia should mean the end of human spaceflight.
If anything, our commitment to space should be radically expanded. The current problems in the space program are the result of all power and authority over the development of space exploration being held in a single decision-making body. NASA, which is a marvelous organization and which certainly provided the basis for the early successes in space, is simply not equipped to move space exploration ahead. It is a government entity, unbound by market considerations, and weighed down by bureaucratic inefficiencies which make radical changes - such as the introduction of new technologies in a cost-effective manner - impossible.
The question, however, must be posed whether space exploration in itself is valuable enough to transfer to the private sector. This question is analogous to the gradual shift in the control of earthbound exploration schemes from sovereign control to chartered corporations. To answer the question, however, without respect to the analogy, no, space exploration in itself is not particularly valuable. It is another medium, another vehicle for transporting humans and their commerce, as well as seeing what's out there. I doubt any private venture at this point would find this to be a profitable scheme without, to be circular, some way to make profits from it.
Thus the analogy: space travel is valuable only insofar as it brings benefit to the people of this planet, or, more specifically, to the shareholders of any corporations which undertake it. In near space, the profits are easy to identify. The GPS system which allows boaters to find their way to fishing spots provided the "spiritual" basis for private venture such as XM Radio. Government-financed spy satellites showed private corporations that money could be made selling space-based imagery of the planet.
But none of these requires human space flight. In order for there to be profit in the human expansion into space, there must be some market for the products which can be produced exclusively or most efficiently in space, whether directly in the case of manufactured goods or indirectly in the case of products developed using experimental data acquired in space. As one discussion group poster noted in response to a question on the necessity of humans to supervise space-based experiments, "It's hard to count ants from 140 miles down."
The International Space Station is a fiasco, and so is the space shuttle. Given the radical developments in materials sciences and knowledge of the effects of space on human bodies, it is as unlikely that the shuttles would have remained in private service for twenty years as to consider that Boeing might continue to build aircraft using the processes and materials perfected during the development of, say, the now-obsolete 727. Even a plane that has had a 30-year lifespan such as the 737 is today not the same plane except in the most superficial way as the first model that flew out of Everett Field.
My plan for space would include the following broad steps. First, ground the shuttle fleet only as long as is necessary to conduct materials review of the launch equipment (fuel tank and rockets), the cooling tile system, and any particularly vulnerable areas of the shuttle's structure (particularly any structural elements on the bottom of the spacecraft). Second, apply any changes rapidly - within no more than two years - with a national commitment to redeploy the shuttle as a stopgap measure in the interests of national security and commerce (as well as prestige). Third, set a hard deadline to retire the shuttles by 2014 at the absolute latest - perhaps 2012 to coincide with the 50th anniversary of American spaceflight. Fourth, provide incentives to corporations to begin manned space flight outside the scope of NASA oversight. Fifth, turn NASA into a regulatory agency for the purposes of establishing safety guidelines; and a science agency which would fund and oversee pure science activities in space. Sixth, provide ongoing incentives for the next two or three decades to promote human exploitation of space by private corporations.
The money for such incentives could probably be found in the monies freed up by the unfortunate loss of Columbia. I would name two incentive packages: the Challenger Fund for the rapid commercialization of space exploration, and the Columbia Fund for the ongoing support of pure science exploration by government or commercial entities. A third package, the Apollo Fund - deriving its name from America's other fatal space mission, Apollo I - would subsidize development of safety mechanisms and alternative propulsion schemes for space exploration.
Our planet is small. Our resources are limited. Only a hundred miles above our heads is the gateway to, literally, a universe of options. There are planets packed with natural resources and room for human habitation. There are asteroids which at once pose a direct threat to our planet and could be a staggeringly rich source of raw materials for the improvement of human civilization. And, as always in a new realm, there is a near infinite space which will provide further insights into this incredible and complex universe in which we are such small but special players.
Now is not the time to draw back from our commitment to space. If anything, we should conclude that the loss of Columbia means that we have reached the limits - after 40 years of remarkable successes - of government monopoly over rich space exploration.
I suspect that the crew of Columbia and their families would agree. After all, they were drawn to the space program because of the opportunity to do something revolutionary, brave, and necessary for our world, not because they wanted to get rich. They would - I hope - support any initiative which would have given them more opportunity to do the work they loved. If we could demonstrate that private control of the space program would, in fact, radically expand that space program - in the same way that private corporations increased and improved the reach of the automobile, the airplane, telecommunications networks, and the Internet - I believe that those astronauts and the astronauts who remain would support us.
Don't give up on space. It is not only our future, but also our present. Make it better, do not declare it dead with those men and women who have died in their ongoing quest to expand the reach and the value of our lives.
the space shuttle IS over-rated.
and personally i hope to see a space-elevator someday. a much cheaper and perhaps a much more environmentally friendly way to escape this gravity well
Logic, macros, and more
Tonight on Studio2, a 3-member panel debated the virtues of the manned space program from a cost-benefit stance, from the human-wonder-fulfillment stance and the most interesting, from the "all of humanity's eggs in one basket stance".
SciFi author Robert J. Sawyer [link] explained that the space program is more than just about vanity, or the desire to prove worth. If it weren't for curiosity, none of us would have left Africa some 6-7 million years ago.
I believe the space program is necessary, because it allows us to test new technologies to their limits. Like pens that can write upside down...
I would also like to point out that NASA seems to be ignoring the first A. That's a great error in my eyes. Atmospheric transportation will always be more common than interstellar imo.
The final thing I have to add, is the fact that humanity will reach a population impasse. Even if (hopefully when) all of the world develops, and rates of population increase drop, consumption of natural resources will eventually deplete reserves. I believe space exploration is but one link in the chain that will lead us away from Earth, and towards a new home. Maybe one with track lighting?
Just out of curiosity, but if we send people to Mars, how in the hell are they supposed to get back? I mean, are they going to set up a launch pad themselves, or will they send a space limo over to pick them up? Is the atmosphere of Mars similar to Earth's?
I have never really heard a good explanation, why we need the ISS and Shuttle, and how exactly are they supposed to help us achieve bigger goals like spreading life elsewhere in the Universe or making spaceflight commercially viable.
Going to the Moon was a good example of the opposite - we picked a real high target, of which we weren't really sure how to achieve it, and set it as a clear goal. And when working toward the goal, we made tremendous advances in science, creating many new practical technologies and materials.
ISS, on the other hand, has never been a grand target, we have always played it safe, always known how it is would be achieved, so basically it is just an expensive toy, there is nothing fundamentally new to be discovered by building it.
If we concentrated our efforts on something bigger, like flying to Mars or creating a Moon base then we might not get immediate gratification. But working towards these tough but clear goals would create a motivation for making all kinds of smaller advances that would all support the main goal, just like they did in the sixties. For example, we could solve the closed ecosphere problem, the technologies from this advance alone would have the potential to significantly improve everyday life.
But instead no one is willing to take risks any more, and we are stuck with doing the same stuff over and over again, putting all sorts of junk in low Earth orbit, something that we have known how to do for ages, and trying to convince ourselves that we are making great progress while actually being stuck in an Escher house.
When men used to be men
The space station provides an excellent oppertunity to inspire and motivate others into science fields. So even if it costs billions of dollars or even trillions, if it means that some kid is motivated into science so that they perhaps discover something like a way to stop ageing or a new metal type, it would be worth it. Plus there is the moral issue, if we can put a man on the moon, and launch people into space and have them live there, doesn't it just show how much we have progressed? I mean if it means more girls end up like the ones at Digital Teenz then perhaps it is worth the risk and expense. But judge for yourself, and remember its your tax dollars at work!
I think that this is an excellent point. Having grown up in the 1980s and 90s, I watched NASA's budget drastically shrink relative to the GDP and I watched NASA stumble along at a terribly slow pace with minimal public support. One can't help but think how great it must have been in the 60s and early 70s when the public was jazzed and scientists were having fun. But this is a frightening point...
Can it really get worse? I personally feel there might be something to this: what happens when a large part of the population suddenly retires, the nation goes broke? Can interest shift further away from space exploration? Is this our last chance to get people interested in NASA before we see an even greater decline in public support?
What do you think?
Die Menschen verhoehnen was sie nicht verstehen. -- Goethe.
Benford apparently isn't aware that centrifuge experiments *have* been conducted on the space shuttle. Or that Columbia was carrying a physiology experiment that would have done a lot for revealing just why exposure to zero-G causes orthostatic intolerance [inability to stand or remain standing].
Specifically, the 1998 STS-90 mission [Neurolab], among other things, studied how humans perceived centrifugal motion in the absence of an existing 1G gravity vector. This mission was designed to study the vestibular system, but others have looked at cardiovascular effects.
The long and the short is that it helps some, but the inertial problem is still sticky. Worse, it tends to make the astronauts sick. Losing track of your vertical tends to make your body do bad things.
A simple review of Pubmed/Medline would have showed all of this. But then, Benford's strength always was was fiction, wasn't it?
Actually, I've read his work. I don't think fiction's really a strong-point, either.
One thing I have noticed on looking at information about the space programs for various country's
I have asked many people lately who was the first woman in space. Invariably the answer is either "I don't know" or "Sally Ride". This is such a pity
The world is amazingly ignorant of the history of space exploration. This is saddening. Considering the absolute minor number of injuries and deaths involved in space exploration compared to what has actually been happening, it is all rather amazing.
The problem at the moment is that space is too expensive; even the Russians charge thousands of dollars per pound, and they've got the cheapest launchers going.
The reason for the high cost? We don't launch enough. The point is that if you look at the technologies out there, this one might save you 20%, that one 10% etc. But each doubling of the number of launches typically saves you 15%; and it's a gift that carries on giving. The minimum cost for launching into space appears to be very low; comparable to the cost of a Concorde flight, the amount of fuel used per person is somewhat comparable.
Therefore we need a purpose for space that requires launching a lot. Space Tourism is likely to meet that niche.
Reliability is of course the second question after price. However, take the Shuttle; it's extremely likely that both crashes are caused by design flaws in the Shuttle; and that the number of flaws that remain undiscovered will decrease over time. Therefore the reliability of the Shuttle should increase, and there's no known limit to how reliable launch vehicles can be.
It seems from surveys that many people would like to go into space, so the interest is certainly there. If the low cost vehicles are available, then it permits travel to low earth orbit. Mars, the moon, the asteroids would then be possible, and it seems that LEO is more than halfway to these places.
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"I say we should turn the asteroid Eros into a space colony. Drill into one end and hollow out a burrow. Add an airlock. Power it with power sats. Then you have a space station. Over time you can build a larger alcove to house hundreds of people. Spin it up to one G. Strap some nuke drive on it and you have a real spaceship.
It's a good point that perhaps we are focusing perhaps too intently on the life lost in the Columbia accident compared to other deathes around the world, but I disagree in part to the idea our expenditures in space are ill-placed.
If we want to develop tomorrow's cures for AIDS or other diseases that grab our attention in horrific ways or otherwise improve our quality of life, we have to expand our knowledge -- in some ways only experimentation in space can. Granted, it's not a panacea for every social ill, but Tower of Babel I think is going too far. The rewards we reap in applications for healthcare, engineering, and otherwise could be used for the greater good or to become a nationalistic bully. However, that's a rather short-term effect.
Instead, if we invest everything now in our close-to-home problems, we might solve those problems. What about the future? We won't be prepared if we don't look ahead.
Be very, very careful what you put into that head, because you will never, ever get it out. -Thomas Cardinal Wolsey
A good point! Here's something that has stumped me for years: Why in bejeepers is everyone gung ho about mars? We've got a perfectly good stepping stone that's 9/10's of the way to anywhere in our solar system parked about 300k kms from us! Not only that, should the need arise, it's conceivable in time of need those stationed there could be evacuated. Perhaps I've just read too much Robert Heinlein (Methusalah's Children, for one. )
If someone wouldn't mind elucidating why the moon is such a poor choice, I'd appreciate it. Please, don't let it be merely that the moon is less interesting politically.
This is so lame...
What is the point of NASA and the Space Administration;
1. Military space support
2. Space-based business
3. Learning about the nature and evolution of the universe.
4. Getting a significant number of human beings off the planet before the sun get's too toasty to support life on the third rock.
The first three items need a cheap and reliable facility for getting hardware up as often as possible. The shuttle was never designed for this duty. The next generation human transport won't be either. There has to be two tracks for getting stuff up there. One track for hardware, flown by wire and robots, managed with a minimum risk to human life.
The next track needs to be a safe, effective, relatively inexpensive way to get large numbers of people off the planet and back again safely. By separating the tasks intelligently we should be able to cut costs and design time, and build optomized systems for the appropriate tasks at hand.
Next we need to stop pissing billions away on pointless millitary spending designed to blast little brown people into giving us their natural resources. There're plenty of resources circling the sun, and the first ones to begin mining them are going to get filthy rich (that includes enough hydrocarbons to float the Iraqi's in an ocean of oil.) We need to stop playing footsies with our neighbors and get the heck off the planet. If we diverted 25% of the millitary budget to space exploration, development, and utilization, we'd be visiting substantial cities at L5, the Moon, and on Mars within all our lifetimes. Things on the big happy checklist of skills to develop include;
1. Protecting people from hard/solar radiation outside the earths magnetosphere.
2. Creating a sustainable, portable biosphere (3 feet of water surrounding a living enclosure would stop virtually all of the hard radiation, as well as insure sufficient water for living in sustained trips into space, and providing a barrier to high velocity microparticles.)
3. Providing artificial gravity, the problems of bone loss are the tip of the iceberg for long term exposure to zero-G. We are optomized for 1 G living and less will causes serious long term problems. We already have the research to indicate the long list of problems associated with zero and low G living. We may even need to build rotating structures on mars and the moon to provide suitable gravity (building structures on rotating arms like a centrifuge, to provide additional artificial gravity.
4. Isolating or biology from their biology. Until we actually begin the serious process of teraforming a planet... we need to make sure their bug don't infect us, and our bugs don't infect them. This is going to be a solid gold bitch. We don't even have a clue how to do this (bacterial sporse can survive vacuum, high temp, hard radiation, and deep cold. In short, we don't even know how to sterilize our tools and ourselves to the degree necessary to indure the saftey of our people and any rare ecologies we may contact.
5. We have to improve our ability to move through space... we have to move so much faster. Chemical rockets are just not going to feed the bulldog, we need to do so much better.
6 We need to come up with a sane means to explore space, in such a way that the entire world receives a share of all the benefits, while those who put up the big wagers, receive a fair portion of the rewards. As it stands, international law, UN conventions, and a variety of treatise, make truly rewarding exploration of space virtually impossible.
7. We need to have a 5, 20, 20, and 50 year plan that suggests we haven't somehow lost our Father's testicles somewhere in the haze of Lunar exploration. Our parents and their parents, had more testicular fortitude in their little fingers that the entire damn nation has in it's 50 states. What kinds of stories of hardship did the persevere through to get to this country and to succeed here, ultimately planting human foot step on the moon. How many of them died striving for something better for themselves and the children's children. We run out of steamed milk for our lattes and life ends are we know it...
I feel for the men and women that died so bravely. I especially feel for their families... now suck it up, don;t make their sacrafice a popcorn fart in the wind, and let's get on with the business of advancing the entire species.
The answers my darlings are out their waving at us...
Genda B.
P.S. If it comes out that this was another avoidable tragedy resulting frmo the cutting of cost and cutting corners by greedy contractors... I suggest the next shuttle be tiled with high level managers from both the guilty corporation and NASA as an indication that we are not amused.
Disclaimer: I haven't read the article. This is about a newspaper article I read yesterday, that I think fits in this discussion.
In the Dutch paper "Volkskrant", there was an opinion piece by a biologist yesterday. He explained that currently, the experiments done in the Shuttle are nowhere near worth their money. The experiments done (like what's the effect of zero-gravity on species x) test no important hypotheses and the outcome is usually not published in high profile magazines.
Once in a while, every scientist working in a field that could possibly have something to do with zero gravity research gets a request for ideas for experiments. They're basically begging for things to add to shuttle science missions. He doesn't really take these things seriously, since these experiments never test anything important. The important stuff (what's the effect of long term zero grav on humans) has been pretty much covered by now.
Also, a Shuttle flight costs $500 million. You can run his institute on that for a hundred years.
So his proposal is to give the $500M to the scientific community instead, to be used for pure science, and see if the scientists themselves spend it on experiments in Shuttles. "Of course they wouldn't".
I believe posters are recognized by their sig. So I made one.
The problem with saying "Let's get everything fixed up here, first" is this: It can't be done. Solving the problems mentioned, and the untold many in tow behind them, would require lifting most of the species to a standard of living comparable to or equal to that of the United States. We do not have the resources to do that, especially if that standard of living includes environmental integrity as well. Where are those resources? In space: Cheap energy, vast mineral resources, no ecosphere to assault.
The evidence is extremely poor that humanity would indeed focus on solving its ills. Most likely, without some driving idea, without a frontier, we will see an increasing self-absorption and a general numbing of our best impulses. As they say, change is inevitable but growth is not... and the only hope lies in growth, in reaching beyond, not back.
The Mongrel Dogs Who Teach
Maybe it would work for bones. I doubt it, but maybe.
OTOH, I can already guarantee it won't do anything for muscle. The only way (yes, the ONLY) way to cause muscle to increase in mass (or to even retain mass) is to force it to work against resistance. That's why people wishing to increase strength lift weights.
Obviously, that's not an option in space. A decent weight set will weigh 400-500 pounds all told, when you have to lift it and pay the weight penalty, and then won't weigh anything at all in orbit. A 275-lb barbell is enough resistance at Earth-surface gravity that I won't try to bench it without a spotter. That same barbell would make for a pretty poor workout when it has inertia, but no actual weight.
Maybe this calls for one of the rubber band contraptions. Bowflex, SoloFlex, and the like are not that great-the best thing to do with them is to call them pop-art coat racks. However, in the absence of gravity they might be the only real option.
Which brings up another question: Has NASA ever put returning astronauts on anabolic androgens? (What the uninformed call 'steroids?') The one legal use they have in humans in the US is to speed recovery from injury, and they might play a part in recovering from long orbits and the resulting bone and strength loss.
Honorable Representative,
The good men and women of the lost shuttle Columbia must be honored. There can be no better way to honor these heroes than by honoring the dreams that led them through the many trials of becoming astronauts. These accomplished men and women dreamed of space exploration with the truest American pioneering spirit. This dream must be honored. The dream must be enacted into reality. It is a most American dream.
We honor the dreams of the astronauts of the Columbia by supporting an aggressive and visionary policy of manned space exploration beyond earth's orbit. No statue or monument can do better justice to our fallen heroes, for a statue or plaque would represent little other than the failure of our American dream; and would commemorate merely the mediocrity of the American spirit. Dream big. No excuses. We must go to Mars.
We must go to Mars. Not for profit, though profit will come by it in the end. We must explore Mars. Not for the glory of America, though glory will come of it. We must embrace Mars as the first step in the destiny of Mankind. That is, outward.
America. She is not Great by Her name alone, but by mighty deeds and kindest embraces we may show the Sadaam's of the world that their cruel hands lead not to greatness, just to mediocrity of human potential. We may make them fearful of our weapons, but weapons will not inspire their dreams of what can be.
Come let us pay tribute to the crew of the Columbia
A Good Troll is better than a Bad Human.
The real tragedy of the space shuttle is that, as Benford says, they were up there doing trivial stuff that we likely could have had machines doing at this point.
His article is spot on. He calls for an era of space exploration akin to that of the late 60's. People died. We had a GOAL. They were heroes. Yet we kept going and we made that goal.
Not only does he call for a return to space exploration, but he points the way - centrifugal gravity and long term stand alone bio-support, aka a biosphere.
So what does it take to overcome this tragedy? I dunno, would a million people sending copies of Benford's article to @whitehouse.gov addresses be a start?
Are we just going to putter around for years and turn this into a double tragedy?
Please let's not.
Operator, give me the number for 911!
Charity vehicles are stolen (by both sides) for use as soldier transports in some parts of Africa. Which do they need most: food and shelter, or another war?
And yes, heterosexuality (or for that matter lesbianism) doesn't spread AIDS anywhere near as fast as male homosexual practice, but the only real blocker is the kind of social arrangement practiced by Christianity or Judiasm. Horrors! We'd much rather die slowly and painfully, taking others with us, than learn from the bigots!
Jews survived the black plague singularly well because they adhered to the `silly' rules in the books of Deuteronomy and Numbers, while their Catholic neighbours didn't. Those rules have reasons behind them. There's a lot that the ancients knew well, but we refuse to learn. At our cost.
Common sense isn't, is it?
Got time? Spend some of it coding or testing
Most likely, without some driving idea, without a frontier, we will see an increasing self-absorption and a general numbing of our best impulses. As they say, change is inevitable but growth is not... and the only hope lies in growth, in reaching beyond, not back.
AMEN.
I think it is time that humanity needs to reach for new frontiers again. The Moon is one place humans should return to, given that we know the Moon has a large supply of strategically important metallic elements, all of which can be used to build space colonies between the Earth and the Moon and also to eventually build spacecraft that will take Man well beyond Mars.
>The problem with saying "Let's get everything fixed up here, first" is this: It can't be done.
Well, it technically can, but that's not the point, I agree.
A few years back, there was a debate with Clarence Page (then-Chicago Tribune) and some right-winger: Does Racism Still Exist? The other guy pulled out his haymaker: If you could only solve one problem in the black community, racism or teen pregnancy, which would you choose?
He makes a good point, but Clarence Page didn't take the bait. His response: why do I have to choose? Are blacks somehow less deserving that we can only work on one problem at a time?
And if you don't think space exploration solves society's ills (okay, works on them), you need to look at the Columbia manifest. Try science.nasa.gov, for starters. It's not an objective, 3rd-party source, of course, but it's still informative.
The moon is a day or two away by chemical rocket. Mars is somewhere between a few weeks (if we build something really futuristic like an Orion drive) and eight months (if we do a minimum-energy Hohmann orbit) away. Mars has an atmosphere, so you can do aerobraking and make propellant out of it, neither of which you can do on the Moon. Mars has a nice diurnal cycle, the Moon doesn't. The temperatures are totally different. The science you want to do on each place is totally different.
If you want a less challenging target for your initial mission, try a near-Earth asteroid. Much more science return - and learning more about NEOs might give us the chance to figure out how best to deflect them.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
Tethers ( 1, 2, 3 ) attached to counterweights can be used to transfer spacecraft from one orbit to another. The first tether has an orbit that skims the atmosphere, where a craft catches and connects to the end of the tether. The craft is lifted into low earth orbit and subsequent tethers help it to reach escape velocity. Using the tethers takes energy out of the orbits of the counterweights, some of which can be put back by using the tethers for descent as well as launch.
J. Storrs-Hall (once moderator of sci.nanotech) envisioned a space dock, a linear motor suspended 100 km above the ground that accelerates spacecraft to an elliptical orbit. He computes an amortized cost of reaching low earth orbit of 42 cents per kilogram. From the elliptical orbit, it's a relatively small safe step to escape velocity.
A space elevator ( 1, 2 ) is an excellent long-term solution. A cable is hung from a weight in geosynchronous orbit, reaching down to the Earth's surface. The elevator climbs the cable, carrying a craft. When it reaches GEO, the craft detaches and spends only a little fuel getting to escape velocity.
Tethers and the space elevator require novel materials for strong cables, probably using carbon nanotubes. The frame to hold up the space dock is in compression, and something we could build with little or no advance in material science. Any of these alternatives would be vastly cheaper and vastly safer than putting human lives on the noses of fuel tanks subjected to unreasonable speeds and stresses.
WWJD for a Klondike Bar?
Firstly while the thicker the atmosphere the better, Mars has only around 1% of our sea level pressure. Although its further removed from Sol, radiation on the surface will still be a significant problem even under tents.
Ambient energy sources from light and thermal gradients are stronger on the moon, and it is cheaper to get heavy things, like mining and plant equipment and nuclear reactors to the Moon than to Mars.
There is probably more ice water on the Moon than we can currently detect, and anyway lunar rock is typically about 30% by weight hydrogen and oxygen, you just have to cook the rock to release it. The 10cm thick glass for (underground) greenhouses can be made on location.
Because the journey there is short, keeping humans healthy and happy enough in transit is almost a no-brainer. Missions can be shorter, cheaper and escape back to Earth is similarly easier.
For the forseeable future, human habitation of other spheres will primarily occur underground; its easy to make a mine airtight and it affords natural protection from solar radiation, not to mention tailings to process for useful things like air and steel. You just need a "space mole", energy to run it, a few airlocks, a suitable sealant, atmosphere, and you soon have as big a habitat as you want, from lifting the minimum weight out of Earth's gravity. This dovetails neatly with the automated mining that will be the primary economic motivation for space development in the mid to long term. Also the lower gravity and greater availability of energy is a boon for mining, making it much cheaper to return the products either to Earth or just to a lagrangian collection point - where a suitably massive Mars colony ship might be built.
Sure lunar gravity is not healthy, but because the moon is closer and cheaper to get to, some of the money saved could be used for underground centrifugally complemented living quarters.
I'm not advocating lunar bases as a population solution, but I think it is a natural stepping stone to start developing before people even set foot on Mars.