New Mars Forums

Everyone seems to be worried about the possibility that carbon nanotubes etc. might cause respiratory problems.
    Well one of my pet hates is diesel fumes and Australia appears to be using some of the dirtiest diesel fuel available in the world at the moment. Following buses, trucks and diesel utility vehicles here is a nightmare, with truly disgusting clouds of dark smoke belching from their tail pipes .. especially when they're going uphill.
    I read a statistic a year or two back which stated that 10,000 Americans die each year from lung disease directly attributable to diesel particulate pollution. And that's in a country where Australia's grade of diesel fuel would be illegal because it's too dirty!!   

    God knows what percentage of Aussies succumb to lung cancer every year from the appalling levels of diesel pollution we're subjected to here! Many European diesel-powered cars cannot be sold here in unmodified form because the fuel is too dirty for the engines to function properly. And nobody seems to care much about it. The last I heard, there were vague plans to raise our standards as regards diesel fuel some time in 2006. In the meantime, it's impossible to drive most places in downtown Cairns with your car windows open without gagging on the smoke. I have the air-conditioning on recirculate ... permanently!

    I suspect that carbon nanotubes could hardly be any worse from a health standpoint than the microscopic carbon particles lodging in our lungs every day from diesel-powered vehicle emissions!
                                          :angry:

    [When I attain absolute power, the people here in otherwise beautiful Australia who have been responsible for this disgraceful state of affairs will be hung, drawn, and quartered and their heads stuck on pikes on Sydney Opera House, while their entrails are fed to the sharks at the local aquarium for the amusement of the crowds!
    ... Sometimes I get quite annoyed about things.] 

How very ingenious and inventive of you, Cindy! 

I hear you, Dickbill.   

    Who knows? ... Maybe the pulverising force of the Hellas event somehow stopped the core rotating and the magnetic field stopped with it .. forever.
                                             

    Such a pity.

And thanks to you, too, Cindy!
    Good stuff ... especially the blind pilot one.
                                       

I wish I'd seen that program, Dickbill. It sounds interesting.
    However, I still haven't heard a hypothesis that ties up all the loose ends of Martian geological history.
    I know the Hellas and Argyre events appear to have taken place after the demise of the global magnetic field, since the floors of these two impact basins lack any 'fossil' magnetic imprint. But to attribute the shutting down of the global field to the swift cooling of the Martian interior, doesn't make sense. There are regions of Mars' surface which carry unmistakable evidence of absolutely enormous outflows of lava in geologically recent times - outflows similar to the eruptions which formed the Siberian and Deccan Traps here on Earth. In addition, it is recognised that the Tharsis volcanoes must have been producing lava well into recent times too, since they are very largely crater free on much of their surfaces.

    I don't think the interior of Mars is cold. I think we'll find that Mars is still volcanically very much alive and I have a hunch Dr. J. Marvin Herndon may well be right about giant natural fission reactors in the cores of planets.

    If Mars did indeed lose its global field 4 billion years ago, I don't think it could have been due to cooling of its interior, a notion which just doesn't fit the facts.
    I think the whole mystery says more about our lack of understanding of how planetary magnetic fields are formed and maintained than it does about Mars' internal heat.
                                                ???

My two cents worth:-
    I agree with just about everyone in this thread ... except Free Spirit.   

    Saying space is "not a place where we belong" could have been applied to all sorts of situations throughout human history. There's almost nowhere on this planet that hasn't been invaded and occupied many times over the millenia and almost every ethnic group has had a go at it.
    It's been mentioned already that early humans left Africa, so current wisdom has it, and spread out all over the world. If Free Spirit's way of thinking had held sway, we'd all still be on the African savannah wondering what the rest of our own planet looked like!
    Even the North American indians are thought to have 'invaded' North America from Asia some 15,000 years ago (I believe), via a land bridge now submerged. Did they have to annihilate any humans who had found that continent earlier? So far we don't think so but it wouldn't surprise me a bit to find out that was the case. Either way, using Free Spirit's logic, you could say that they they took over a place where 'they didn't belong'.
    Today's polynesian islanders have only been on their idyllic tropical islands for a few thousand years, having spent many weeks in open boats to get there from places in Asia. Often the journey would have been an act of faith since the Pacific Ocean at the time was more unknown and therefore more dangerous than interplanetary space is to us at present. Again, those people were taking risks and suffering hardships in order to go where 'they didn't belong'. These days everyone is perfectly happy to call them South Sea islanders and nobody disputes their right to be where they are.

    I may be wrong, but I suspect Free Spirit is harbouring more than a little disgust for his own species, perhaps for reasons Cindy has pointed out. But, as she rightly says, brooding in bitterness and guilt for perceived past crimes is a negative, self-destructive, and entirely useless activity.
    For my money, I think Free Spirit would do well to shake off such feelings and look at the good things humanity has done and is capable of.
    Space is our next frontier. It's a place of hope for the future and should be seen that way.
                                         

It doesn't matter much about introducing terrestrial micro-organisms into the Martian soil if Nozomi crashes onto Mars.
    The Russians beat the Japanese to it about 40 years ago when they were crashing completely unsterilised probes onto the Red Planet in a hurried effort to outdo the Americans.

    Rxke's comment about terraforming taking place "a bit earlier than envisioned...", might be quite an understatement!!
                                                       

Mad Grad Student:-

    That got my curiosity aroused and I did a bit of googling to see just how much material there actually is in the asteroid belt.
    It turns out there's about 2.3*10^21 kg of material in the belt, compared to our Moon's mass of 7.35*10^22 kg, which is roughly 30 times as much.
    Assuming a rough parity in density, I calculated that all the present day asteroid material, if gathered into one body (and ignoring the effects of gravitational compression), would form a planetoid with a diameter of about 1100 kms.
    Its surface gravity would be about 0.05g

    This is a rather more substantial body than I'd imagined it to be, judging by the references to it that I've read over the years. And it does sound easily big enough to constitute a respectable moon for Mars in your imaginary scenario, Mad Grad. In fact, it's about half the diameter of Pluto!
    Indeed, if you take into consideration the likelihood that a sizeable portion of that moon would have been lost in the process of disintegrating, which means the asteroid belt today might represent only half of the total original material, then your hypothetical 'Martian Luna' could well have been even bigger.

    I'm not sure, though, how you would explain all that material from the destroyed moon leaving Mars all together and forming a ring of debris in solar orbit. And you have to explain also why that debris chose just the right distance from the Sun to comply with Bode's Law - assuming Bode's Law has any significance other than coincidental, of course!

    As to the timetable for exploration if Mars had been found to have a dense atmosphere and seas, I would guess we'd have sent people there by the 1970s.
                                                     

And again ... from Downunder !!
                                                      

I may owe the Americans here an apology.
    When President Bush was addressing the Australian parliament a week or two back, he was heckled badly by two Greens Party senators.
    First of all, I'd like to say I was appalled at the unforgivable bad manners of those two hateful individuals. There is no excuse for such behaviour towards an invited guest of the Australian people, no matter what you might think of his/her politics. Some Aussie politicians wrote letters of protest against the Iraq war and presented them to Bush at the end of the speech. That, in my view, is a legitimate and dignified means of expressing dissent and I defend their right to do so, but draw the line where it impinges on the natural right of others to say their piece. The Greens attempted to deny your President that right.
    Second, I apologise in case it was the outburst here in the Australian Parliament that encouraged the presidential minders to establish their exclusion zone around your Chief Executive!
                                             

    If it's true that Clinton and Gore restricted access to anti-abortion activists and got away with it, how is the Republican attempt at doing the same with anti-war activists any different?
    Or is it a dual standard of reporting based on whether you are perceived as more liberal, i.e. Democrat, or less liberal, i.e. Republican?
    Do left-leaning journalists tend to 'look the other way' if a Democrat oversteps the mark a little bit, while raising hell at similar Republican behaviour? I think we may need to be a bit more even-handed and consistent, if that's the case.
    Just a thought.
                                        ???   

Cindy:-

    This is very true!
    Having been fascinated with the concept of vast tracts of time since childhood - I originally wanted to be a paleontologist - I've developed a perspective on things which is 'bigger' than most of the people I've spoken to about such matters. It's a mixed blessing, too, because it can do one of two things: First, it can make you wonder what the significance of human life really is, considering we're so small and our tenure here so brief; and secondly, it can make you appreciate how special we are in this enormous ancient universe, with our ability to contemplate the workings of the very cosmos which gave birth to us.

    But Cindy's recognition here of the fragility of the conditions in our stellar neighbourhood, which allow us to continue living and even allow our solar system to continue existing(! ), has a bearing on our approach to things like terraforming Mars - or at least, I believe it has.
    This is a violent and very changeable universe. Our existence is not guaranteed any more than our solar system's existence is guaranteed. Just because things look so stable and quiet in our region of the galaxy right now, doesn't mean they won't be chaotic and deadly next year.

    It may be that sentient life appears rarely and, perhaps, briefly and sporadically in this universe. Maybe it's unusual for a planetary system to remain relatively undisturbed for long periods, as ours seems to have done, whereby life can take hold and survive over geological time spans.
    My view is that time may be short; shorter than we think. We need to live for the moment, 'seize the day', and take advantage of any good prospect for advancement that comes our way.
    I see Mars as a golden opportunity to make mankind a multi-planet species, to expand our range and our technology to a point where our survival as a species is more likely. Ultimately it will lead to us spreading out across the galaxy, establishing new civilisations hundreds of light years away. All of this will be an insurance policy against the snuffing out of our kind of life by some sort of cosmic catastrophe, such as a 'local' supernova like the one BGD mentions.

    I think we need to be less 'conservationist' about places like Mars, where life holds on by its fingernails (if it holds on at all! ), and should take the present chance we have to improve its ability to nurture life. If there is indeed a wholly alien form of life there somewhere, then by all means go softly, but we shouldn't 'conserve' ourselves into oblivion in an attempt to save Mars in its present state, just to have a nearby supernova sterilise our whole solar system a few years later anyway!
    Mars is a gift. It's an astonishingly Earth-like planet right next-door which we can cause to blossom and sustain life on its surface. If we don't take advantage of this golden opportunity, given to us by providence in an unusual display of cosmic beneficence, then we're all fools and deserve whatever disaster comes our way.
    Such chances are rare. Let's grab this one with both hands!
                                                     

Just adding my two cents worth, in agreement with Byron, it is good to have new members and I add my welcome to you all!