New Mars Forums

Somebody contact "Looney Tunes".
    I think we're onto a new story line here!   :laugh:

Hi Dook!
    I don't have a problem with you expressing your opinions about mass, velocity, gravity etc. Relativity is far from intuitive and takes a lot of mental wrangling to get a handle on, if you ask me.
    Personally, I find it useful to express opinions, such as you have done, because it becomes a learning process in itself. The more you discuss something like this, the more you develop your understanding of it - but only with helpful input from others, I think.

    I've never heard of the concept of gravity being an exotic form of EM radiation but I can see how you might get around to thinking that way. Scientists talk of gravity particles, gravitons, speak of detecting gravity waves (see LIGO), and speak of gravity as travelling through space at the speed of light. And, as you rightly point out, gravity and light intensity both diminish as the square of the distance.
    I can see very clearly how a person might decide EM radiation and gravity must be different manifestations of the same phenomenon.

    I don't profess to be an expert on Relativity, by any means, but I think the stumbling block to your hypothesis, at least from the viewpoint of mainstream science, lies in the nature of space-time as it relates to gravity. GCNRevenger and Robert Dyck are trying to explain this to you and I don't pretend to be able to do that better than they have already. But, in the spirit of open discussion, and knowing that the more you chew these things over the more sense it gradually makes, I'll just reiterate a little.
    I think the point is that EM wave/particles are seen as energy which propagates through space-time, while gravity is seen as a distortion of space-time itself.
    So, a photon is like a fish moving through the water, while gravity is like the undulation of the water itself.

    As I understand it, this is what makes the unification of gravity with the other fundamental forces so damnably difficult. Quantum Mechanics is good at describing the behaviour of particles, including the 'force-transfer' particles such as photons and gluons, but is much harder to apply to something like gravity which involves dimensional distortion. This is why we have the two powerful edifices of Quantum Mechanics and Relativity, cornerstones of modern physics, engaged in a kind of cosmic Mexican stand-off!   

    I'm hopeful that eventually Quantum Mechanics will be able to explain gravity, perhaps via the Higgs boson which has been in the news lately. And, given the bizarre nature of this stuff, I wouldn't be surprised if gravity is actually found to be a higher-dimensional manifestation of EM radiation, or some such exotica! Who knows?
    In a round about way, Dook, you may be found to be closer to the truth than even you yourself really think!
    As has been said: "The universe is not just stranger than you imagine, it's stranger than you can imagine."
                                               

Interesting picture of a domed crater on Luna, guys. Thanks. I don't think I've ever seen that one before. I love the striking contrast between the colourless desolation outside the dome and the vibrant colours of water and life inside it.
    At a rough guess, the dome looks about 20 or 30 kilometres across. Past experience of the kinds of theoretical implications of such a vast structure tell me the foundations holding the dome down will have to be colossal. A dome with a diameter of about 1 kilometre, containing a 500 millibar atmosphere, exerts an upward force of about 3.36 million tonnes [See Page 2 of 'Domed Habitats' on Page 3 of the 'Life Support Systems' Topic].
    Assuming that dome on the Moon is 20 kilometres across, the upward force of a 500 millibar atmosphere inside it will be over 1.62 billion tonnes!!
    That's gonna take some seriously massive (or massively strong) foundations - especially when any ballast you use weighs only 1/6th of what it would weigh on Earth! With this in mind, I don't honestly believe that big beautiful lunar dome is possible. Such a shame.
                                       

Hmmm ... I don't know, Cindy.   ???

    Wishing for dust-devils over Spirit and Opportunity might cause a faster build-up of dust on the solar panels and, well .. you know what that would mean .. ?!!
                                             

    On the other hand, I suppose it's feasible that the dust that's already accumulated on the panels may actually be swept away by the high winds in a dust-devil.
    Naaahh!! I don't want to take the risk.
                                                             

Hi Dook.
    I've never been able to work out how bricks could be used in the hostile building environment Mars presents us with. Any habitat we make will be essentially like a potential bomb - threatening to explode outwards at any moment due to the pressure inside. Even a minimal 350 millibar atmosphere inside a habitat will result in over 3 tonnes/sq.m trying to get out!
    Persuading bricks and mortar to hold together under those circumstances seems an impossible task. And how can you mix and apply cement in a freezing virtual vacuum and get it to set properly in the first place?!
                                                  ???

    Some time ago, here at "Life Support Systems", on page 3, we discussed building techniques at some length under the headings of "We need a brainstorming session" and "Domed habitats .. " (especially the latter heading).
    You might care to have a look at the posts there and then give us your views on what can be done(?). My opinion is that we'll need either completely new techniques of construction or we'll need to use old techniques within the protective confines of pressurised spheres etc.
    Any thoughts?
                                                     ???   

Hi REB.
    I think there may well be more than a grain of truth in what you say about differences between Meridiani and Gusev.
    Meridiani is at the shoreline of what was probably the martian Northern Ocean eons ago. The Northern Ocean is purported to have occupied the northern lowlands and may have existed for millions of years. I can imagine that the water in that ocean would have become progressively saltier as minerals were washed into it over time from the higher land to the south - either by runoff from precipitation in the earliest period or by the release of water from aquifers in later periods.

    On the other hand, Gusev crater was almost certainly filled with no doubt fresher runoff water from the vast highland lake system to its south.
    See http://www.nasm.si.edu/ceps/research/ir … s.htm]THIS SITE for images of the lake and drainage system in question.
    Although the eventual catastrophic release of the bulk of the lake system waters probably caused the breach of Gusev's northern wall, thus allowing salty Northern Ocean water to enter the crater, Gusev was probably a fresh water lake for much of its history.
    This may account for the differences in the geology, as you suggest.

    To me, it's only a matter of time before definitive evidence of inundation by water is found at Gusev. When you look at the satellite images of the extensive lake system to its south, the deep and sinuous Ma'adim Vallis leading into it, and the crater itself, it becomes impossible to conceive of a plausible alternative.
    I'm looking forward very much to what Spirit might find in the layers of the Columbia Hills.
                                                 

I've said it before and I'll say it again: You're all a great bunch of people and I'm honoured to know you.
                                     

    Thanks very much for taking the time and trouble to send birthday wishes to 'an old geezer' ( ... thanks a lot, Josh!  :laugh:  ) !!

    At least Cindy managed to resist the temptation to be .. erm, how shall we put this .. impolite .. about my advanced years! At my age, I'm grateful for small mercies.
                                                  :;):

    And yes, Rik, I will try to be careful about which candles I blow out!
                                             

As non-American outsider, I also get the impression that Kerry is 'a man for all seasons'. It looks to me like he probably has an agenda but doesn't feel the need to say anything much about it. Kerry thinks Bush is so unpopular at present that just waffling and looking the part will be enough to get him elected.
    My suspicion, looking at the way he talks about the subject, is that Kerry will place a lesser emphasis on space exploration - particularly manned exploration. Since my main reason for being here at New Mars is my passion for human exploration of the solar system, I don't like the sound of what Kerry is saying.

    Mind you, it is very hard to know what Kerry is thinking just by listening to what he's saying!
                                                         

Interesting shots. It looks a little like 'someone left the cake out in the rain', doesn't it?
    I don't mean rain, literally, but those termite galleries look a bit like the beginnings of stalactites - as though a nearly saturated chemical solution has been dripping down and leaving that characteristic 'curtain' type of deposit you sometimes see in limestone caves here on Earth.

    Can't wait for the press conference. I wonder what they've come up with this time?
                                                        ???

I think it's very civilised we can all agree that politics in the wrong threads is probably going to happen, to at least some extent. But that we can all self-regulate, making a brief relevant political point, perhaps, while resisting the temptation to expound at length on off-topic material, is an indicator of the intelligence and goodwill of most members of New Mars.
    I've always thought that the great majority of people really want the same kinds of things but just disagree over the best way to achieve them - we're all part of the same species, after all. A long-term rational debate, however fruitless it may appear to be in terms of changing people's opinions, is the best way to very gradually work out our differences and achieve genuinely useful compromise.

    This is the only 'chat room' type of site I've ever participated in but, according to others here, I've hit the jackpot!
    Taking them at their word, having no reason to doubt them, I must say I do appreciate the wonderful and good-natured exchange of viewpoints here at New Mars.

    Take a bow, everyone ... you're a pretty good bunch of people!
                                          :up:   

I think Bill is right!
    If we're sending a Hab, a fuel synthesiser, and a nuclear reactor to Mars in advance of the people (a la Mars Direct or similar), an earthmover and maybe a few tonnes of aluminium with an extruder would surely be well worth the extra launch.
    The reactor will be producing a lot of heat as well as electrical power and could be pressed into service to soften aluminium. With various extruder 'profiles' (sorry, don't know the proper terminology), many useful structural members could be fabricated in situ.
    Some kind of reinforced polymer sphere of a suitable size needn't weigh a vast amount and, in deflated form, would be quite compact.

    Nobody here wants a 'flags and footprints' fate to befall Mars exploration. Bill's plan constitutes thinking ahead and makes perfect sense to me.
    Far from "going big and inviting a catastrophe", the more technology the astronauts/colonists have available to them, the less chance there must be of a disaster occurring.

    Just an opinion.     

Hi Cindy!
    You might find http://www.marsbase.net/]THIS SITE useful, once you find your way around the various abbreviations.
    As you probably know already, UTC is just the modern-day term for GMT.