New Mars Forums

Knowing the way the mind of the average 'person-in-the-street' works, I think Dr. Zubrin's appearance on that show is probably detrimental to our cause.
    It's hard enough, in the face of condescending tongue-in-cheek reporting of space news by scientifically illiterate TV journalists, to get the public to take space exploration seriously. If the Mars Society, however incidentally, becomes associated with people who are perceived to be (or are routinely portrayed as) 'flaky', then we will all be tarred with the same brush!

    I believe this is the reason our own webmaster, Adrian (long may his tenure continue! ), confined talk about extraterrestrial intelligence at New Mars to one section. And it's also the reason he penned an elaborate disclaimer at the beginning of that section, where it enjoys pride of place, pointing out the true agenda of The Mars Society and placing distance between it and the world of the 'flying saucer fraternity'!

    None of us here is likely to confuse the wise words of Dr. Zubrin with the wild rantings of the lunatic fringe. But, unfortunately, the rest of the world can't be relied upon to display the same critical discernment.

    So ... my opinion? Somebody tell Bob to stop doing it!
                                       

Hello Wayland321.
    First of all, welcome to New Mars! The more members the merrier!!

    Mars has enough gravity to hold onto a very substantial atmosphere for a very long time. By 'a very long time', I mean long by human standards. For example, if we were successful in terraforming Mars to the extent that we created an atmosphere of 500 millibars of CO2, it would take hundreds of thousands (or maybe millions) of years before a noticeable drop in pressure occurred due to leakage into space.
    Our 500 millibar CO2 atmosphere would probably have super-greenhouse-gases mixed into it and Mars would be much warmer than it is today. If so, we could have large bodies of water - vast lakes or even oceans - in the low lying regions. This could be problematic with a CO2 atmosphere due to a weathering process whereby the CO2 dissolves in the water and becomes incorporated, permanently, into carbonate rocks.
    I have no figures to back this up, and maybe microorganisms are necessary to really move this reaction along (using dissolved CO2 in the water for shell formation), but I suspect weathering at the bottom of the atmosphere  may remove CO2 quicker than leakage from the top!
    Ultimately, an atmosphere of nitrogen and oxygen would be our goal, though creating that may be considerably more difficult than the CO2 version. (This may not be the case but, with the present state of knowledge, it seems likely.) We would have less trouble with a nitrogen/oxygen atmosphere dissolving into our new seas, but would trade that problem for the more difficult task of keeping Mars warm without all that CO2!! There's always a catch!  :;):

    The features of the Martian topography which look like they were produced by water, probably were produced by water! Geologists who understand the different kinds of erosion - wind, water, ice-shattering etc. - have concluded that wind, sand, and ice are unlikely in the extreme to have been responsible for all the features we see. Most of the valleys, channels, and obvious sedimentary features could realistically only result from water erosion.
    Logically, if water erosion over periods of AT LEAST tens of thousands of years has occurred, then atmospheric conditions must necessarily have been clement enough to allow this. And apparently there is evidence to suggest that such clement episodes may have occurred periodically throughout most of Martian history, possibly even into geologically recent times.

    Waddya think, Wayland321?! Are you convinced?
                                   

You're right again, Dickbill!
    I suspect your politics and mine are quite different but I applaud your objectivity in this.
    Auqakah's article smells very badly of B.S. if you ask me!! (No offence intended towards him, by the way.) I believe it epitomises attempts by certain politically motivated organisations to play on the good nature of ordinary people who genuinely abhor inhumanity.
    I am simultaneously encouraged at the decency of such ordinary people (who want nothing but peace) and, at the same time, appalled at how easily they are deceived and manipulated by the scum of these far-left-wing organisations, who will sink to any depths to further their agenda.
    Those who know me well from these pages will remember I love a good conspiracy theory, but I do recognise melodramatic crap when I see it!!
                                       :laugh:

You're right, Dickbill.
    The remnant crustal magnetic fields on Mars are stronger and more extensive in the higher, cratered southern regions than in the northern lowlands or in Hellas.
    This makes it impossible, as you mentioned, to take advantage of both magnetic and atmospheric shielding at the same time.   

    For an interesting article (not new, but still good reading! ), try this site.
    It seems there are at least some places on Mars where there's complete shielding from the solar wind. But it doesn't look like this will be helpful for exploration or settlement, since we can hardly confine ourselves to these small areas simply to avoid charged particles from the Sun. If we're going to be that worried about radiation, our best bet is to just stay home!!
    Apparently, though, there are places between the strips of magnetised crust where the solar wind is channeled straight down onto the surface! My assumption is that these particular zones would have a higher than average flux of charged particles from the Sun and would be places for explorers to avoid.

    The consensus of opinion among those who ought to know, e.g. Dr Zubrin, is that radiation exposure can be minimised by keeping Earth-Mars transit times short and using regolith or natural caves for shielding down on the surface. Air-shielding under large domes or in tented valleys will be helpful in the medium/long term, while eventually a planetwide thicker atmosphere would be ideal.

    I haven't been able to find projections for the rems/year new Martians can expect to receive after we establish an atmosphere of, say, 500 millibars of CO2. (If that's possible.)
    That information will give us a much better idea of how colonists will ultimately fare in the new world.
                                     ???

I like your independence of thought, Gennaro!
    It seems you and I are in agreement about this. More research would certainly appear to be warranted. And I haven't seen NuclearSpace say anything unreasonable about this so far. All he wants is a fair hearing for the concept - and is prepared to scrap it as and when the evidence shows it to be non-viable from an environmental viewpoint.
    I can't see a problem with this attitude. It's called science!!
                                           

As some of you know (to your cost! ), I've often preached about Earth and Mars swapping bits of themselves due to impacts. Dr. Paul Davies agrees with me (! ), or should I say I agree with him(!!! )  , that this phenomenon will almost certainly lead to Earth-like organisms being found alive on Mars when we get there. I've even championed the notion that Dr. Gilbert Levin's Labeled Release experiments aboard the Viking landers detected that very same life in 1977. But I digress.

    In a recent informal discussion, Freeman Dyson talked with Bruce Murray and Louis Friedman, of The Planetary Society, about interstellar travel. The discussion was recorded in the latest edition of TPS's magazine, "The Planetary Report".
    They covered the usual stuff about sending unmanned probes first, using powerful lasers or microwaves powered by our Sun to propel giant dish-shaped craft at speeds up to maybe 0.5c (half light speed). Then they moved on to the idea of manned craft - theoretically possible, but not until we've got about another 500 years of technological development under our belts!

    What really interested me, though, was Freeman Dyson's reference to an astronomer called Jack Baggaley in New Zealand, who works with a project called AMOR - the Advanced Meteor Orbit Radar. According to Dr. Dyson: "He actually sees stuff arriving here on Earth from Beta Pictoris, which I find very delightful. So we're already getting interstellar stuff, and it's being measured and observed."
    Later in the same article, he went on to say: "The fact that we're getting stuff from Beta Pictoris also changes one's view of panspermia - the idea of life moving from place to place in space. If there are creatures living around Beta Pictoris, then they're probably already here. If an organism is already adapted to living in a vacuum, interstellar travel is not all that big a problem."

    This was a stunning revelation to me! I had no idea that an ongoing interstellar transfer of material had been established scientifically. It certainly does add weight to the concept of panspermia in general, though perhaps not in this particular case.
    Apparently Beta Pictoris is a blue-white main sequence star, 50 light years distant, roughly 1.75 times the mass of the Sun and about 8 times as luminous. Not a show-stopper for life so far .... but there is a hitch! It is estimated to be only about 200 million years old. Probably not old enough for any circling planets (and there are some) to have yet given birth to life.
    That's not to say that Beta Pictoris couldn't have acted as a gravitational 'relay-runner', whisking dormant life forms in the interstellar dust onwards toward us from somewhere even further away!
    The possibilities are endless!

    And it makes the transfer of viable spores between Earth and Mars look positively pedestrian!! - And all the more likely to have happened very frequently throughout the history of the solar system.
    What a wonderful universe!!!   

Yes, Robert.
    The scenarios you describe are, of course, all feasible. Even the 172 millibar O2 atmosphere, with CO2 reduced to 1 millibar for human consumption purposes, is marginally acceptable as far as temperature maintenance is concerned. I put these figures into Martyn Fogg's Terraforming Simulator, with CH4 set at 5 microbars, NH3 at 50 microbars, and CFC at 2 microbars. (I understand that CFCs are NOT desirable for the reasons you mentioned - but ignoring that for the sake of argument). With the above atmosphere, and making no alteration to albedo or insolation, the projected temperature figures came out:-
          Mean global          +4.5 deg.C
          Polar                   -35.1 deg.C
          Maximum tropical   +32.2 deg.C
    The planet would be above freezing at latitudes up to 37.7 degrees. Using this as the theoretical boundary for settlement (an arbitrary boundary), this makes 61.2% of the surface habitable.

    But, as has been pointed out, producing such an almost totally O2 atmosphere - even if that were the desired outcome - may not be achievable in the short term. It seems more likely, at least with our present understanding of the volatile inventory, that a chiefly CO2 atmosphere might be easier to create.
    Using the same simulator, a 400 millibar CO2 atmosphere, with the same partial pressures of greenhouse gases quoted above, would be considerably warmer:-
           Mean global          +13.6 deg.C
           Polar                    -11 deg.C
           Maximum tropical   +42.2 deg.C
    Producing a surface above freezing up to latitudes of 59 degrees and making (arbitrarily again) 85.7% of the surface habitable.
    As Dr. Zubrin explains, although we would need domes over our settlements with such a poisonous atmosphere, they could be made very large since there would be little pressure difference between inside and outside and massive foundations would be unnecessary. The atmosphere inside could be 50% oxygen and 50% nitrogen, producing a very Earth-like O2 partial pressure of 200 millibars.

    I still think a soletta will probably be necessary to prevent freezing of any large bodies of water in the northern lowlands. Such freezing would produce large areas of ice with a corresponding increase in albedo and greater reflection of sunlight. A runaway refrigeration effect would follow.

    [P.S. I think BGD might be confusing millibars with microbars. 1200 millibars of NH3 would probably raise the average global temperature on Mars above the boiling point of water!]

I just love all this conjecture about how things would look and behave on a terraformed Mars!!

    Being an Aussie, I love surf beaches (something which bugs me at the moment because we currently live in the 'shelter' of the Great Barrier Reef - no surf!!    ), so my mind keeps coming back to the shores of Oceanus Borealis.
    I try my hardest to imagine walking on the sand as a brisk cool north wind brings in the breakers from the Utopia Sea. But the waves, though taller, fall slower and softer and with less of a 'crash' than they do on Earth. And the sound is gentler and more muted in the attenuated air. And then there's the beautiful Martian sunlight - bright and clear, but without the harsh glare of Earthly sunshine - like wearing medium-tint sunglasses without having to wear sunglasses!

Cindy:-

    You said it, sister!!!  I'm ready to go!   

Awww, shucks Ma'am ... you know I'm just a fool for compliment from a young lady!!

There seems to be contradictory information flying around already. Cindy mentioned a US senator accusing Bush of not listening to the people. But just yesterday, a Washington Post poll showed 71% of the American people now support the war. (The figure for Britain was quoted at 50%.)

    I know there are "lies, damned lies, and then there are statistics", but my impression is that the Washington Post has a reputation for leaning a little more to the left than the right - is that actually so? At the very least, I thought it was regarded as one of the top newspapers in the country.

    The legality or otherwise of the war in Iraq will be of no consequence when it's all over. Historically, whoever wins a war was right, whoever loses was wrong. America will win and any question of right or wrong will be moot.
    That's how it's always been in history and that's probably how it always will be in all future wars.

    So far, because of the British Empire and, now, the military ascendancy of the US, the English-speaking peoples of the world have been lucky. We haven't been on the losing end of a major war for centuries. (Putting aside small differences of opinion like the American war of independence and glossing over embarrassments like Vietnam, I mean!)
    And, as I've said, if you always win, you're always right. Even if you're wrong, you're right - or, at least, you are never called to account for what you've done - unlike the losers.

    It's a good and noble thing for protesters to decry the crimes of nations like America, Britain, or Australia (though Australia has less clout so we cop less bagging - the jealousy factor is less intense against us.)
    But we mustn't forget how lucky we are. If some country like the former Soviet Union were the only superpower left standing, instead of America, there would be no question of consulting the UN about anything. There would be no question of airing your opinions or grievances in the streets either.

    So far, the 'right' countries are, by and large, winning. However much you may love to hate them (and there are doubtless very valid reasons to do so), you really don't want to contemplate the alternative. It's still a very brutal world out there.

Please excuse my ignorance in these things but I noticed Ad Astra mentioned an Atlas V with "three common booster cores in parallel".
   
    If three booster cores can be used in parallel, in my mind's eye I can imagine four more being attached - for a total of seven booster cores all together!
    First of all, is such a thing possible or practicable? And, secondly, if it were to be built, what kind of mass could it place in LEO?
                                          ???

Cindy, this thread of yours really is largely a labour of love, isn't it?!
    You put such a lot of effort into reproducing lengthy excerpts from the writings of various prominent people of the 18th century, while getting only occasional responses from interested parties!

    I myself confess to being guilty of neglecting this thread much of the time, though I do 'drop in' now and then for the  refreshing taste of a more gracious era (at least for some). I do admire the way language was used in those days. It looks so quaint by comparison with our utilitarian use of words today but has a peculiar beauty about it which I find still  influencing my way of thinking for some hours after I've read it. And not just influencing my mental use of words. I actually find it has quite a calming effect in general - almost as though the slower pace of life of the 18th century is conveyed through time by the words.
    Call me slightly wacky if you will!   
    I just love the way Charles Dickens uses language, too!