New Mars Forums

I can't direct you to a specific source of information, HeloTeacher, but from the old cerebral memory banks (such as they are!) I don't believe atmospheric leakage is a problem.
   I've read heaps of stuff about Mars and terraforming over the years, and the general consensus of expert opinion is that it takes tens of thousands or hundreds of thousands of years to lose a significant amount of atmosphere from a place like Mars.
   Certainly, your brand new atmosphere will immediately start to drift away into space, but it is so gradual (at least from a human perspective) that it will be no problem to keep up with it by importing gases from elsewhere. It's important to remember that humanity will be advancing as each century passes, so our technological ability will be increasing faster than the air is leaking!
   It's difficult to imagine what technological marvels we will take for granted in a thousand years from now, so I think you can safely ignore this problem for the time being. Let's concentrate on MAKING the damned atmosphere first ..... we can worry about losing it later!!   

Phew, gbbaker !! Your Posts add up to quite a tour-de-force on the topic of terraforming!
   In my more sober and pessimistic moments, I get to thinking that the whole terraforming thing is wildly optimistic. But I think it was Sir Arthur C. Clarke who, in examining where luminaries of the past had had trouble in predicting future advances, said that often it boiled down to a failure of nerve. And with the quickening pace of technological improvement, I have to say I'm inclined to agree with gbbaker ... always assuming the existence of the political will and the cash!
   As for the conservationists, rightly concerned about indigenous Martian organisms, I don't think it will be a problem. As I have said elsewhere in New Mars (more than once, I think!), Mars has never been biologically isolated from Earth, due to impact transfer between the two planets of viable bacteria and mould, or their spores. This is now common knowledge but it seems that most people are unable, or unwilling, to assimilate this information into their world-view.
They still cling to the now outmoded idea that life could have arisen independently on Mars and Earth and never interacted. Not so!
   The transfer of life-bearing material must have been two-way; Mars to Earth and Earth to Mars. Yet in all our travels and scientific studies all over Earth, we have never found any life forms based on anything but good old RNA/DNA and the same set of familiar amino acids. What this tells me is that life arose on EITHER Earth or Mars (not both ) and was spread to the other planet by meteoritic impact. (The only other possibility is that life arose independently on each planet but one type completely outcompeted and eliminated the other at some stage in the past ... but I doubt it.)
   So the kind of life we have here is the kind we will find on Mars. And I mean 'WILL FIND ON MARS', because life is enormously tenacious! Ancient life on Mars, whether from there or from here, will have survived into the present without any doubt (and been supplemented periodically with new arrivals from Earth). Maybe not as obviously as the Gaia theorists would have us believe, because the Martian surface conditions are so ferociously hostile, but it is there ... somewhere. Maybe we've been looking right at it, in the form of some of the surface anomalies noted by NASA, but have failed to recognise it for some reason; another failure of nerve, perhaps!
   Anyway, the point is that we won't need to concern ourselves with a philosophical debate over native Martian life-forms, and the morality of killing them. Martian bugs will be the same as Earth bugs and anything we do to make Mars more Earth-like will only be advantageous to those bugs, ... and to us! Is everybody O.K. with that? Excellent. 
   One other thing: Although ecopoiesis may be relatively easy (we hope!), I'm inclined to side with those who believe the apparently poor nitrogen inventory on Mars could end up as the limiting factor in totally transforming the environment. Does anybody know whether any of the asteroids contain large quantities of frozen nitrogen? If they did, of course, there would be the prospect (a la Kim Stanley Robinson) of steering a few into Mars' atmosphere, along with some big watery ones!!
   Any thoughts or rebuttals on any of this ... ? (Incidentally, I prefer Blue to Red!)

This is all great fun to think about but I can't get the nagging feeling out of my mind that it might be a little premature. I know, I know ..... if I can't play nicely with the other kids and only want to spoil the game, then I should go to my room!!
   O.K., I'll be good! ... One question I did think of relates to radiation and U.V. light. I imagine the dome material, whether transparent or opaque, can be made impervious to U.V. or even engineered to allow through a modicum of U.V. if necessary, for plants (do they need it?) or just so you could still get a nice tan by the pool! Incidentally, for what it's worth, I tend to side with those in favour of transparent domes for psychological reasons. In fact I would even suggest making the anchoring structure around the perimeter as inconspicuous as possible to enhance the "open-air" feel of the place.
   But what about particle radiation? How much air, presumably at pressures of 1 bar (is that what we're aiming for?), would be needed to block most of the damaging stuff from space? My point is this: If thicknesses of tens of metres of dense air were to make any difference to radiation flux, and if the "tallest" dome is hemispherical, then the bigger the diameter of the dome the better. If lots of air between you and the dome is a good idea, then make the dome a hemisphere with a kilometre radius; thus giving yourself a thousand metres of lovely gaseous protection above your head! (At least in the middle of the dome.) And, as a bonus, you could build high-rise buildings to conserve space inside the dome for recreational purposes, and get great views out over the rugged Martian topography.
   Now watch while an expert rolls up and blithely informs me that you need way more than a kilometre of air at 1 bar to make any difference to radiation from space!! And after all that hard thinking I did, too!
   Well ... did I play nicely? And does anyone wanna take the ball and run with it?!

Thank you RobS and Bill. It's always gratifying to find that others can see what one perceives to be a problem, and that they concur.
   For so many years now, people have spoken routinely of the lead the Russians have in the study of the long-term effects of microgravity; usually with reference to Mars missions. I have never been able to generate any enthusiasm for these studies because the effects are all bad, the prospects for fixing them are all bad, and the ramifications for a trip to Mars under these conditions are all bad!
   Maybe startling advances in space medicine over the next half-century will produce a pill you take twice a day in space, which will keep you in perfect shape no matter how long you spend in zero-g. But for now we need centripetal force.
   It seems to me that whatever engineering problems may be involved in rotating a manned interplanetary spacecraft, they pale into insignificance next to the plethora of medical problems you face if you don't rotate it!
   I'm looking forward to any further comments or ideas you may have, RobS, Bill, and anyone else interested in this topic. I thoroughly enjoy this Forum and feel encouraged at the obvious depth of talent and knowledge among Mars Society members. It's a privilege to "meet" you for a chat! Thanks again to all of you.

Well, I had a look at "SCHEME" and I didn't like it much. The rigid truss idea is O.K. as far as it goes but I think it just doesn't go far enough.
   The radius of spin (you know what I mean) is only 20 metres, which means you have to have the craft spinning at 4 revs per minute to generate a mere 0.38g. The first problem I have with this is that 4 revs per minute has been shown to be more or less the limit as far as adaptation to the disorientating coriolis effects is concerned. So the astronauts gradually get used to the cockamamie way things fall and the swirling feeling in their heads every time they bend over, and then at Mars you "spin-down" the craft and they have to adjust back. And this at a time when they need to be razor sharp! The second problem, and this seems to be common to all the proposed mission-structures, is that nobody seems to want to provide artificial gravity on the way home! It's the "Don't worry, they're coming home to medical help" mentality. As I've said, after 500 days on Mars at 0.38g and 180 days in space at zero-g, I simply can't imagine them ever adjusting back to Earth gravity; with medical help or not! Ignoring this problem is futile; it ain't gonna go away!!
   Assuming that trusses are always going to be too heavy/bulky to be used in any significant lengths ... and I mean hundreds of metres ... there seems to be no alternative to cables on spools. And I'm not sure what might be used for a counterweight on the way home (is there a practicable modification that could be made to the  Mars Direct mission structure to provide for this?)
   I note the concern about a pressurised access tunnel between the two spinning craft. Am I to understand that it is feasible or desirable to attempt to transfer from one craft to the other while they're spinning? Surely the weight transfer would cause some kind of instability in the system, wouldn't it?
With cables, if you need to get at something in the "ballast" craft, you would simply spin-down, wind in the cable, dock the two craft, and open the hatch. Simple!
   And now I've had time to think about all this spinning-up and spinning-down for course corrections and other purposes, I've decided the perfect thrusters for the job would be those low-thrust ion motors. They're very efficient and don't need too much weighty propellant ... and who cares if it takes a couple of days to do the job when the journey time is measured in months!
   And one more thing: I still think we should be aiming at more than 0.38g, whether outbound or homebound. Doesn't anybody out there agree with me? Imagine your weight suddenly increasing from, say, 180 pounds to 470 pounds! That's what it's going to feel like to those poor astronauts, even if we DO give them 0.38g on the way home!!
   Well?! ....

It seems that almost every article you read about Mars is based on the same premise, that Mars was once warm(er) and wet. The main problem with this hypothesis being that there seems to be no way to model an early Mars with enough atmosphere and enough insolation (solar input) to get the surface temperature above zero.
   You can imagine a 5 bar atmosphere of CO2 soon after accretion of the planet, which would provide a nice cosy greenhouse effect .... IF there were enough heat coming in from the sun for the atmosphere to trap! But then you have to contend with the "dim young sun" problem. (I know, I know ... it sounds like an item on a chinese menu!) This refers to the fact that 3 to 4 billion years ago, the sun was only putting out about 70% of its present heat and light. Even today, with 43% of the insolation Earth gets, Mars is a very cold place. When you factor in the 70% output, early Mars was only getting 30% of the warmth we are basking in today.
   If you suddenly throttled back solar output arriving here on Earth today to just 30% of the norm, we would be plunged into the mother and father of an ice-age from which we would never recover. So, even with that 5 bar CO2 atmosphere we conjured up, it still seems impossible to produce a climate on early Mars which could be deemed anything but freezing cold!
   Exotic solutions have been put forward to try to get around this difficulty, including a dense cabon-dioxide atmosphere with high-altitude clouds of CO2 crystals. According to theoretical models, this would be a very effective "blanket" for Mars which would keep the surface warm enough for liquid water to exist. The only drawback being that Mars would have been continuously overcast for many millions of years.
   It seems to me that making up exotic theoretical models in an attempt to explain the data, probably means that you have the wrong data or that you have the right data but not enough of it!
   Then there's this guy Hoffman from Australia! He thinks Mars was never warm and wet. He maintains that it was always bitterly cold and bone-dry and that its surface features, so reminiscent of water erosion, were caused by floods of liquid CO2 mixed with rock and dust! No water necessary. And he must have developed this idea to a significant degree, too, because at one seminar he apparently had more than half the "watery Mars" advocates doubting themselves.
   But then again, I have a magnificent globe of Mars which I bought on the net from "Sky and Telescope". It is a topographical globe, color-coded to depict the relative height of the terrain, with the high ground in shades of orange and red and the lowlands in green and blue. It is based on the most recent Mars Orbiter Laser Altimeter (MOLA) data and is therefore highly accurate. I would recommend it to anyone with an interest in Mars.
   The point of all this is that when you look at this globe with its valleys, channels, and flood-plains, it just screams "WATER"! Large areas look 'smudged', just like a sand-castle that has been washed over by a wave! Craters in the northern basin have breached walls and highly eroded rims; some appear to be so buried in sediment as to be almost too feint to see. The whole planet gives every indication of having had water on its surface. And I don't mean some paltry amount of water! I mean the whole place must have been awash with it!! Buy,steal, or borrow one of these globes and have a really good look at it; I think you'll have to agree we're talking about millions of cubic kilometres of good old H2O here! Not liquid CO2. If it looks like a duck, waddles like a duck, and quacks like a duck; chances are it is a duck! And when you see this globe, you'll be able to TASTE the water on Mars!
   So where does that get us? Back to square one. I know Mars had to be warm and wet; maybe it even had extensive precipitation for lengthy periods in its history. But how do we explain it? Could Mars' internal heat have somehow contributed to a warmer climate? Could there have been more powerful greenhouse gases in the early Martian atmosphere?
   As to the fate of all that water, I'm afraid much of it has been lost to space. But not all of it. There may still be enough in vast aquifers to create lakes and even small seas if the surface were warmer and the air denser. Stand by for more data from Mars Odyssey which, a few weeks ago, may have found hints of large quantities of water under Vastitas Borealis.
   Can anybody add to this Post and maybe enlighten us all as to this vexed question of water on Mars?

I sense your disgust with NASA over its glacial progress toward a manned Mars mission! I empathise 1000%!!!
   It seems that every time they have another meeting, they come out of it with a longer and longer time-table of less and less ambitious missions. They really do need a fire under their tails to wake them up. I think a lot of the trouble comes down to the same old thing: Risk. Nobody wants to do anything audacious or exciting any more in case it doesn't work and they're left with egg on their faces. It's a symptom of today's world that risk-taking is politically and culturally unpalatable.
   The problem is that virtually nothing can be attempted without at least some risk. And great strides forward can rarely be taken without quite substantial risks. I often think about the Apollo astronauts and the things they did with clunky 1960s technology! That whole program was so far ahead of its time it's hard to believe, in retrospect, that it was ever tried. And the raw courage of those astronauts has been very greatly understated.
   But getting back to the point: You write as though there is actually some possibility of the Mars Society pulling off a major coup by retrieving a piece of Mars ahead of the major space agencies! Are you serious or just making a rhetorical point? I mean, how much would it cost and where would we get the money? And what about a quarantine facility? From what I've read, you need an enormously intricate and expensive building just to process the samples in biological isolation.
   I'm not trying to rain on your parade but I'm having trouble digesting this idea. Surely there is just no way for a small space-advocacy group to really contemplate such a mission? Please somebody .... explain to me why I'm wrong. I'd love to be wrong!!

This Translife experiment is a great idea because I don't think we can subject people to zero-g for 6 months and then expect them to perform well in a new and hostile environment. It seems to me that rotating the spacecraft on the way to Mars will be essential and, therefore, we need to find out as much as we can about the effects of "artificial gravity".
   What is NASA's position on this problem at the moment? Are they investigating the prospects for separating the Mars craft into two sections connected by cable(s) and "spinning it up"?
If so, how difficult would it be? Presumably a spool of kevlar maybe one or two kilometres long wouldn't weigh much, but what about thruster fuel for spinning up and then spinning down for course-corrections? Are these problems likely to be "show-stoppers" or just minor technical difficulties we can solve with a bit of practice in LEO.
   Incidentally, for what it's worth, I think we should try for the longest practicable tether length in order to maximise the g-force with a relatively low rotation speed. This will minimise the coriolis effects. What I think we should aim for is a full 1g of artificial gravity on the outward trip and only 1 revolution per minute. To my mind, this will deliver astronauts in the best possible shape mentally, and especially physically, at Mars. It may be just as critical for the homeward leg of the trip too because, after 500 days on Mars in 0.38g and 180 days in zero-g, it might prove impossible to adjust back to full Earth gravity.
   Any information or criticisms?

There is an interesting article in New Scientist (12 January 2002) which describes the work of Evgeny Podkletnov and Ning Li into a potential new form of propulsion.
   It seems that these two researchers worked independently; Podkletnov in Finland building a gravity-modifying machine, and Ning Li at the University of Alabama in Huntsville developing a theory which may explain how that machine works.
   It seems that the work was sufficiently plausible to attract the attention of Ron Koczor of NASA's Marshall Space Flight Center, who has commissioned Superconductive Components of Columbus, Ohio to build an exact copy of the purportedly gravity-shielding machine. NASA paid $600,000 for the privilege and takes delivery of its new toy this month. Mr Koczor has stated that the series of experiments planned for the device should take no longer than six months to run, by which time we will know if it works or not.
   I don't pretend to understand how this machine works from a theoretical standpoint, though the diagram of its components appears relatively uncomplicated. But a doctorate in theoretical physics is not required in order to grasp what this invention will mean to the world, should it be found to work as advertised! I won't attempt to list all the things we could do if we could control gravity but the implications for space travel will spring readily to mind if you're a Mars Society member, like me!
   The purpose of this Post is really just to make sure that as many people as possible know about this important event; especially motivated and determined people, like us. I don't want this story to sink without trace the way other potentially history-changing developments seem to do. I want this laboratory testing at the Marshall Space Flight Center to be done openly, with appropriate reporting of progress, and with a comprehensive conclusion published at the end. And I want it whether the machine works or not! (If you are an American citizen, footing the bill for this through your taxes, you should be even more adamant than I am.)
   So let's mark off the 6 months on our calendars and, if we've heard nothing by then, let's start asking questions. This is very exciting stuff!!