Instead of using a magnetic sensor where you need to go up close to the ground. Could one use a camera that sensed heat waves instead be used? I suppose the mines are metal encased. So just wait for a hot sunny day, even if the mines are buried a few inches under, metal aborbes more heat than soil throughout the day. So during the afternoon, take out your heat sensing camera and you'll see all the hot spots.
Better yet, since this is a world wide concern, maybe our wonderfull Hubble can turn it's focus for a moment from outer space back to our down to earth minefield problems, look at a couple of minefields, spot the hot spots, give out the GPS locations of those troublesome critters.-- wisewhiskers, Nov 29 2003 This idea hinges on the proposition that metal things heat up more quickly than the surrounding soil. I am not sure if this is true. But if it is, you could use the infrared camera to find them, and also could do the same trick at the beach to find washed up doubloons. I am wondering how to go about testing this. But from me, bread for an interesting approach to a serious problem.-- bungston, Nov 30 2003 Hence, Bungston, the proof that it doesn't work that way: if it did, someone would have done it.
This might sort of work if land mines were on the ground instead of under it. Metal underground isn't exposed to sunshine or ambient air; its source of heat is the ground around it. A mine is well insulated from the changing climate and thus can only change temperature as fast as its surroundings. Also note that, while it absorbs heat faster, it also radiates heat faster.
Note that the fact that metal absorbs more heat would tend to make it a cool spot when exposed to direct radiation.
Also, the Hubble is an optical telescope. Also, there's this whole atmosphere thing that gets in the way of telescopes, which is why we put it up in space at great expense to begin with.-- darksasami, Nov 30 2003 I agree wholeheartedly with [darksasami] //Hence, Bungston, the proof that it doesn't work that way: if it did, someone would have done it.// Everything that can be done has already been done.durrrrr. (+)-- neilp, Nov 30 2003 /if it did, someone would have done it/ Anathema!
I am still pondering the idea of using cameras to find mines. Satellite scopes may be a little distant but plane based would not be outrageous. I do agree with [darksalami]'s reasons why infrared/heat based is not the way to go. I wonder about using longer wavelengths - UV or even longer. Perhaps some penetrate deeply enough to show mines? You would have planes fly over taking photos of those wavelengths, then match the images to gps-obtained coordinates.-- bungston, Nov 30 2003 We already know that there are expensive and time consuming ways to detect mines; Armoured vehicles and magnetic sweepers. Our goal is to find an inexpensive way to do it so that third world countries, farmers, and poor country side folks can do it themselves.
It would be great if a soldier had to walk and was caught without minesweeping gear, could simply whip out a digital camera ( with unfiltered lens) and use it to peer the lanscape he was walking and avoid any hot spots that he sees. Why hasn't it been done before? Because digital cameras were not available until recently and it's getting very cheap.
I got this initial idea because two of my digital fuji camera started having similar problems after about a year. They would show other strange colors exuding from the scenary. Looked just like the special effect in the movie "Predator" when they showed how the alien looked at us with his heat sensing eyes. I also see it in cameras placed at Asian airports to detect slightly higher temperatures of passengers for SARS.-- wisewhiskers, Dec 01 2003 random, halfbakery