New Mars Forums

Thanks Karov.
    I haven't really considered the M2P2 in any great detail before and your link was very informative. It's quite a concept, when you think about it, sounding like the ultimate 'bootstrapping' technique - with the plasma conducting the current, which makes the magnetic field, which in turn constrains the plasma! 
    It really is a remarkably elegant idea, if it can be made to work in practice.

    But I don't see how it could be used to shield a planet. The M2P2 thruster is actually enveloped by the plasma cloud it produces; i.e. the magnet/plasma generator sits in the centre of the cloud, except of course when the solar wind acts upon the cloud and causes it to 'billow out' to some extent, away from the Sun.
    Ideally, I suppose, you'd position your planetary M2P2 thruster (or shield, in this case) at Mars' core, but this is impracticable. If you position it at some point in space, presumably sunward of Mars in the expectation the cloud will billow out toward and around the planet, how do you propose to prevent it shifting? Even if you place it at the Sun-Mars L1 point, won't its vast plasma cloud tend to move it away from the stable point? Perhaps you know of a modified L1 point where the gravitational fields of Mars and the Sun, and the lateral force of the solar wind on the plasma cloud, are all in equilibrium?  And wouldn't the Martian ionosphere interfere with the inflation of the plasma cloud anyway, as it expanded to engulf the planet? ???
    I just don't see how you plan to make it work.

    As for the Mars-girdling superconducting cable, if its creating a magnetic field through and around the rotating planet, this will create eddy currents in the planet's interior, and thus secondary magnetic fields opposing the planet's rotation. Of course, these eddy currents and secondary magnetic fields will have a completely negligible effect on the planet's rotation rate because Mars is such a massive body, but they must necessarily cause energy loss to the system by creating heat which is ultimately dissipated through convection and radiation. (Please correct me if I'm wrong.)
    Since there's no such thing as a free lunch, I think you'd have to pump energy into your cable to maintain the current, even if the cable is superconducting - which it would have to be in any case to maintain such a massive current over a distance of 21,000 kms. Any appreciable resistance would surely become problematic over distances far less than that.
    And we're assuming we'll have materials which superconduct at average temperatures of maybe 290K on a terraformed Mars, of course. Presumably not a problem in the future we speak of.

    Oh, and unfortunately I have no idea how to go about "re-exciting natural mag-fields". All I'm hoping is that Mars will automatically re-start its global field as and when the fission products 'poisoning' its nuclear reactor core float out of the core and allow the chain reaction to once again heat the interior of the planet and create the convection currents necessary for that field to exist.
    But all this depends on the vindication of Dr. Herndon and his controversial hypothesis. 

Yes, Karov.
    I do understand the basic principle of using a vast loop of current to create a planetary magnetic field. In fact, if I remember my physics correctly, the existence of an iron core inside a planet would serve to enhance the efficiency of such a field(?).
    And I do realize that, given sufficient energy, engineering prowess, and human willpower, there's no fundamental reason we cannot undertake such a task.
    And, what's more, I do admire your vision when it comes to planetary-scale engineering and your obvious enthusiasm for such projects. I also look forward to the time when such amazing feats of technology will be achieved - and I admit they may be closer than I imagine. Perhaps I'm too timid. Perhaps I'm forgetting what Sir Arthur C. Clarke has taught us, that most failures of prediction stem from a failure of nerve - technology almost always advances farther and faster than most of us foresee. So you may well be right to pursue this line of reasoning so vigorously. 

    One or two particular thoughts I'd like to air, by the way, while I'm on the subject .. I always imagine that any loop of superconducting material around Mars' equator will need to be able to carry such an enormous density of current that it's construction will be untenable for a long time. Also, I wonder whether the localized fields generated by the massive current will have detrimental effects on the environment in the immediate vicinity of the equator.
    There are questions being asked here on Earth about the potential (pun unintentional .. sorry! ) for power lines near residential communities to cause cancer - and the electric current in these cases is negligible compared to the current we'll need for our Martian project.  If so, will it be necessary to fence off large swathes of equatorial real estate to establish a safety buffer zone either side of the cable?  ???
    Admittedly, even if such a buffer zone were necessary, we may decide that it's a fair exchange - to lose so many millions of hectares of habitable area at the equator in order to allow unfettered colonization of immense areas of radiation-shielded land to the north and south. Who knows?

    Personally, my hope would be to create an atmosphere dense enough to shield the surface from harmful radiation, even in the absence of a global magnetic field. I feel that this is probably a more attainable goal in the short term. Such an atmosphere, it's been established, will last for millions of years, despite the ravages of constant 'sputtering' by the solar wind and the blasts of Coronal Mass Ejections (thank you Cindy for alerting me, and perhaps others here, to the surprising power and frequency of such events.  :up:  )

    Just touching on a 'pet theory' dear to my heart. I still have hopes that Mars is much more volcanically alive than it's been given credit for and that it may still generate a substantial global magnetic field at intervals. This pet theory, as I've often mentioned, depends to a large extent on the as yet unconfirmed ideas of Dr. J. Marvin Herndon about natural fission reactors in planetary cores.
    Earth's magnetic poles reverse every so often, with the North Pole taking up residence in Antarctica and the South Pole moving to the Arctic Ocean. Have a look at http://www.gi.alaska.edu/ScienceForum/A … .html]THIS ARTICLE, called "When The Poles Flip" by Larry Gedney. :-

    If Mars is still geologically active, it seems reasonable to assume that its poles reverse periodically too - perhaps more sluggishly than Earth's since its smaller volume means it's probably losing energy to space faster.
   It follows that it must also have intervals during which there is no global field, just as Earth does. In the case of Earth, these intervals may be years long or thousands of years long - no one knows for sure - and any such intervals on Mars may be correspondingly longer.
    My view is we could conceivably have arrived at Mars, just by chance, during one of these pole reversals. We could be pleasantly surprised, in the millenia to come, to find our Martian colonies protected by a brand new natural magnetic field, without having to create it ourselves using mega-engineering.

    On that 'Pollyanna-style' note of fairy tale optimism, I'll sign off.   :laugh:
    (Thanks for your patience.  :;):  )

Hi Karov!
    I don't know if your cable around Mars will work to create a planetwide magnetic field or not. Perhaps it will and I hope it does some day. 

    As for the CO2 turning into sedimentary rock, all we have to do is ensure that the pH of the Northern Ocean and various seas is kept sufficiently acidic. Not acidic in the sense that it would be dangerously corrosive to humans enjoying a day at the beach, but just acidic enough to preclude the formation of carbonate rock.

    Apparently, this can be achieved as long as the pH is kept less than 6.2, as described in this Abstract of a paper called "Inhibition of carbonate synthesis in acidic oceans on early Mars", by Fairen AG, Fernandez-Remolar D, Dohm JM, Baker VR, Amils R. :-

    The absence of significant carbonate deposits on Mars is very encouraging to us serious terraformers as it tends to remove the concern that any early Martian CO2 atmosphere has been lost irrevocably to dissolution and sedimentation as carbonate rock.
    This would seem to indicate that the remnant atmosphere, which escaped blasting into space by meteoritic bombardment in the earliest epochs, has probably been adsorbed onto the regolith, as suggested by many authorities including Dr. Zubrin. This adds credence to the notion that warming the Martian surface could indeed release maybe 800 millibars of CO2 and maintain an efficient greenhouse effect.
                                                                  :up:   

Extremely interesting thoughts as usual, CM.  :up:
    I see your point about a possibly unstable salty crust. I did a little speculating myself, earlier in this thread, about possible salty mud being the culprit responsible for Oppy's plight, but your 'dry crust' explanation may be more realistic.
    As Cindy rightly suggests, shouldn't we be analyzing the soil more closely with the Rover's cameras?  ???

I guess the answer, in the long term, will be cars with electronic I.D. If, once identified by police as involved in something reckless or illegal, it's impossible to hide a car, chases will be unnecessary - they'll get you later in the supermarket carpark or your own driveway.
    I suppose tagging all vehicles electronically is one more incursion of 'Big Brother' into our lives, though.  ???

Nice work, Reddragon!
    For me, the 'piece-de-resistance' was this verse:-

Where else shall our explorers go today,
With nowhere left on Earth to wander far,
And each frontier a cellphone's call away?
Again we go where yet no people are.

    Sums it up well, in my view.   :up:   

[P.S. How on Earth did Bill manage to drag the Rep/Dem tribal war into this thread, too?!! 
       And shame on you, CC, for encouraging him in his barely sub-clinical obsession.    ]

It's a tricky problem.
    Iran will soon have nuclear weapons and it already has a very capable missile delivery system. One of its stated national objectives is the total destruction of Israel, which is a nuclear power itself. We can only hope that the religious nuts running Iran will understand the futility of an actual nuclear exchange and never attempt to use their arsenal.

    Socially, it appears from media reports (can we believe them?) that most of the Iranian population wants a secular government, or at least a watered-down version of the present theocracratic arrangement. The maturation of a democratic government in neighbouring Iraq will probably do much to nudge Iran along that road, without any external interference.

    The Syrian and Iranian regimes will go on covertly attacking the people and the infrastructure of Iraq because they know a successful democracy in that country will necessarily undermine their dictatorships.
    For this reason, a steady death-toll of maybe 5000 Iraqis per annum, with bomb damage to buildings and roads, will go on indefinitely. This will continue regardless of the presence or otherwise of Coalition troops, since it is essential to the continued rule of the despots in Syria and Iran.

    It's a grim account to keep but we have to compare the situation before and after the liberation of Iraq. Many more people were slaughtered on a regular basis by Saddam before the liberation than are dying now at the hands of Syrian/Iranian/Baathist murderers.
    And today, the Iraqis have their own future in their own hands - a gift of inestimable value after all they've had to endure.

    Every day, for the sake of the brave Iraqi people, and for the sake of the Coalition troops who've done such a great job, (as well as a hope that theocracies and totalitarian regimes will be weakened by it) I look for news of success in Iraq. Not easy to find, with world media so biased against America and her allies and doing whatever they can to present the worst side of the situation.

    Never mind! Time will tell. 

Hi Weave, and welcome to New Mars! 
    It looks like you browse through the MER microscopic images, as I do, checking for anything which might be a fossil.
    I have to admit, I find this picture intriguing, too, and I'm glad you've drawn our attention to it.

    I suppose this is the kind of terrestrial lichen you think this Martian object looks like(?) :-

    I remember reading something by Dr. Carl Sagan (I think) which asked how an explorer on an alien planet might recognize life if she saw it - considering that the life forms there could take on exotic shapes and forms unlike anything seen on Earth.
    He suggested that the astronaut could look for a shape which is ordinarily unstable in a gravitational field. The terrestrial analogy given was a tree. An oak tree is an essentially unstable structure, which no inanimate matter is likely to emulate. Entropy would work against such a structure forming unless it were a living thing using energy to cause a localized reduction in entropy.
    For this reason, if you saw something similarly unstable on another world, it would be worth investigating, even if it didn't look like any living thing you'd ever seen before.

    It seems to me your Martian lichen looks unstable. It appears unlikely a leaf-shaped piece of .. whatever it is .. could have fallen onto that rock and be sitting there in what looks like such a precarious position:-

    But , if you ask me, there's a problem.
    Why, out of hundreds of microscopic images, would there be just one tiny 'leaf' of lichen on one tiny rock? ... Just one, all by itself?  ???
    If there were many of them protruding at all angles from several rocks, as in a colony, it would be much more impressive. The fact that it's only one makes it very much more probable it's just an unusual mineral formation.

    At the moment, and lacking any further data, I don't see how we can see it as any more than that - just a peculiar non-living  oddity.
    Does anyone else have an alternative argument? I'd like to be proven wrong. 

Ah, I hadn't seen this more recent news. Very disappointing.
    Never mind, Bill; keep your chin up! There's always tomorrow. 

Thanks, GregM.
    This is the kind of discussion I was trying to elicit. I note your opinion that the MPL's rocket exhaust, even though widely spread in the near vacuum of Mar's atmosphere, would still have no trouble at all disturbing dust on the surface from 40 metres up.
    I confess, though, I'm still having trouble visualizing that scenario because the darkened surface patch in the image (whether it's actually that dark or not) seems so tightly constrained to the immediate vicinity of the crashed probe itself.
    But, then, what do I know about the behaviour of rocket exhaust in such circumstances? All I can do is express an opinion.
                                                             
    Any other opinions on this?

Rik:-

    I didn't know much about the characteristics of rocket plumes in a vacuum until I read the scientific refutation of the "Apollo Moon Hoax" nonsense. One of the points made by the conspiracy theorists was that the Descent Module rocket didn't produce a crater and didn't really leave a very prominent blast mark either. (Naturally, these fools deduced that this helped to prove the lunar landings never took place.    )
    Anyhow, the explanation of the lack of significant scarring of the surface by the LM's descent-stage rocket included information I think is useful in evaluating the effect of the MPL's retro-rocket.
    I found http://www.badastronomy.com/bad/tv/foxapollo.html]THIS SITE, which includes the following about the LM's landing rocket:-

    This is what led me to think the MPL's rocket, if it cut out at 40 metres altitude, in what is effectively almost a vacuum, wouldn't have left such a prominent dark marking on the Martian surface.
    It looks to me as though the rocket kept firing all the way down.
    Does anyone agree ... or have I erred somewhere in my logic on this?  ???   

Cindy:-

    Hmmm, yes. I wonder what the 'Great Attractor' really is?

    Maybe it's a super-mega-hypergigamongous black hole, eleventyseventeen-tera-squillion times the mass of the Sun ... drawing us all faster and faster to our grisly doom in its gaping maw?!!
    Sheesh. Where's Captain Kirk when you need him?