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Thread: Sleepy Cartography Inspiration and GAY help to confirm it!

  1. #1 Sleepy Cartography Inspiration and GAY help to confirm it! 
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    I often think I'm seriously lacking in inspiration and creativity, but this story proves that I'm not so bad when I'm asleep!

    The only background I have in cartography was gained through high school geography (which I finished 16 years ago) and through still depending on maps regularly to make sure I don't get lost in the African wilds, so take this question from where it comes!

    About ten years ago when I woke up one morning, the moment I opened my eyes I realised that I was dreaming about a projection method which would solve a certain cartography problem that my high school teacher couldn't solve!

    The basic problem, as you all know, is that any map becomes distorted towards the sides and corners, because the map is a flat (2 dimensional) representation of a round (3 dimensional) object. Two objects that are in reality exactly 1 kilometer away from each other and which appears on the side of a map (especially a map with a large scale) will seem further away from each other than two other objects that are also exactly 1 kilometer away from each other in the centre of the map.This can easily be visualised by imagining that you are hovering in a helicopter above the earth and what you see when you look down should be exactly what you see on a map of the same area. The problem is that the things you can see towards the horizon is much further away from you than anything right beneath you and there will therefore be a distortion in the percieved distance between objects when you draw (project) the picture of what you see beneath you on a flat piece of paper (a map).

    The revelation I had in my inspirational dream was that the only place you could "hover" the hypothetical helicopter without experiencing this problem would be the centre of the earth! From there every point on the surface would be roughly the same distance from you and if you project a map from there you wouldn't have the same problems with distortion! After thinking about this revelation of mine I realised that a map that was projected from the centre of the earth onto a flat piece of paper would still necessarily have some sort of distortion (maybe an evenly spread distortion that is not more pronounced towards the sides than in the middle) because the map is still a flat representation of the round earth.

    I therefore filed that dream into the "useless mental breakthroughs folder" in my brain, where it remained untill the following incident happened about six years ago.

    I was on a inter-continental flight from South Africa to Brazil when something went wrong with the in-flight entertainment system and, to cut a long story short, I helped the obviously gay flight attendant who was all flustered and in a flat spin to sort out his problem. Back then I was still a professional athlete and in great shape, so the combination of my help and my muscles really caused this guy to take a big liking in me! He almost pleaded with me to tell him what he could do for me in return. I'm not quite sure if he had some kind of mile high club thing in mind (ouch!), but I asked him if he could organise a visit to the cockpit for me. This was still a year or so before 9/11, so the security wasn't that tight and he quickly hauled me off and into the cockpit.

    I had a nice long chat with the pilot and co-pilot and they later offered me a seat next to the Navigation Officer. During our conversation he told me (completely out of his own) that the maps they used on those long flights were (from quite soon before that time) projected from the centre of the earth to minimise distortion! I was thrilled to hear that my dream actually had some merit to it and that the idea that came to me in my sleep completely independantly from any other source was actually used in international aviation!

    To get to my actual questions. Firstly, nobody I've spoken to since then could confirm anything about what that Navigational Officer told me. Secondly, with the accuracy of modern GPS, would a projection method from the centre of the earth still have any relevance or application in aviation or navigation?


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  3. #2 Okay.... 
    Forum Professor leohopkins's Avatar
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    Okay....

    First of all; congratulations ! You were VERY brave to ask that flight attendant if you could see the COCKpit. I would have favoured "flight dEck" in that situation to avoid any embarrassing mis-comunication : - )

    Secondly; you are not alone, I too sometimes have inspirational thoughts and sometimes dreams which later turn out to be correct.

    Thirdly all GPS does is give your position over the sphere; it could be a great big ball of snot for all the GPS is concerned. Terrain mapping etc, thats still done, yes. And yes you are right it is "projected" from the centre of the earth. (not literally of course) but mathematically. Infact, go out and buy a normal globe; as the information on this would have been printed using the same methods.

    Now what I would be very interested to find out is; would it be possible to have an sphere of glass, possible an LCD "globe" (which you plug into your computer) and it will run a complete weather model of data retrieved from the internet, so you can see current flows, tides, winds, thermals, volcanic activity and clouds cover. That would be an interesting thing to have. Even more so if when you disconnected it from its data souce it would "remember" patterns of weather behaviour and take a shot at predicting the weather, then you plug it back into the computer to download real world weather for it to re-calibrate its-self and give you a reading of by how much the predition was "off" the truth.


    The hand of time rested on the half-hour mark, and all along that old front line of the English there came a whistling and a crying. The men of the first wave climbed up the parapets, in tumult, darkness, and the presence of death, and having done with all pleasant things, advanced across No Man's Land to begin the Battle of the Somme. - Poet John Masefield.

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  4. #3  
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    Yeah, you're right about the COCKpit thing, I'm lucky to have come out of that one unscathed!

    The LCD globe thing you're talking about would be a great toy! I'm sure it wouldn't be impossible to do, bacause the international weather bureau's certainly already use live global weather charts and use it to make their weather forecasts! The problems I foresee with the globe toy is firstly that there must probably be a HUGE ammount of calculations and memory needed to run the thing (depending on the "resolution" you want) and you would basically need a super computer to handle it. On the other hand, if you were happy with only major weather systems being shown it would probably not take that much calculation. Also, just showing what is actually happening would be much easier on your computer than predicting what will happen in the future!

    Secondly, I'm not sure if the "picture" you want to be shown on the sphere can easily be done.

    That you're idea would be a very nice toy and that whoever can make it a reality will probably make LOTS of money is clear to me! Maybe you should give it a go? Al you need is a live feed from the National Weather Bureau and a way of projecting their maps onto a glass sphere and you're a millionaire!
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    I would buy the 'weather globe' if it's not too expensive, it's a great idea :wink:

    About the map projection, I don't really see how a projection from the center of the earth would work. Map distortions arise because you start with a globe (the earth), which you then want to project on a flat surface (the map). Try cutting a football to pieces and laying them out as a map, you'll have to stretch the parts to make them fit together (especially at the 'poles'). That's exactly what a cartographer does. In the end you'll either have to stretch all parts a little bit (sacrificing either continental shapes, distances between places or directions between places), or settle for a map that consists of loose pieces that don't fit together.

    Wikipedia has a good article on map projections.
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  6. #5  
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    Thanks Pendragon.

    As I said in my initial post, I realised that it doesn't matter from where you project, you'll always have the same problem if your final map is on a flat piece of paper. That is why I filed the idea in my Useless Mental Breakthroughs folder!

    I was actually mainly intrugued about this because of what the Navigational Officer said to me. He specifically mentioned the fact that they project from the middle of the earth, so there must be something to the whole idear.
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