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Using Google Earth to Find Ancient Cities
An anonymous reader writes "A story in the online site of the Aussie science mag Cosmos discusses how archaeologists are using sophisticated satellite images to find previously undiscovered cities. What 's really cool is how some are simply using Google Earth — and discovering all sorts of previously unknown sites!"
Here goes:
http://www.cosmosmagazine.com.nyud.net/node/1764
Water absorbs electromagnetic waves very quickly, making radar useless for detecting underwater objects. Accoustic waves are propagated very well though, which makes sonar an excellent choice for underwater surveying. The only thing satellites can image is the ocean surface. If the objects of interest are in very shallow water and visible from the surface then satellite images may be useful. Anything deeper than a few feet won't be detectable without side scan sonar.
The weirdest thing about those satellite images is that they are NOT satellite images.
Many people are under the mistaken impression that Google Earth ONLY uses satellite images. That's simply untrue, and anyone who reads the GE FAQ would know this.
Those photos are aerial mapping photos produced by an airplane flying "tracks" across the city. They are then stitched together to form a mosaic, and since this was done with public funds the images are available to google earth for a modest fee. Seattle has similar images.
Any time you see the sides of an object on google earth it is NOT a satellite photo.
Sig Battery depleted. Reverting to safe mode.
The first usage of aerial photography for archaeological purposes dates back into the 1920's. Using aerial photography and radar for searching out sites of archaeological interest was covered in National Geographic back in the 1950's. I remember seeing in my dad's photogrammetry magazines from the 1960's, aerial photography services specifically advertising their availability for archaeological surveys. (As well as multiple articles in the magazines on that very topic.) A book of NASA terrestrial photography I own from the 1970's dedicates an entire chapter to the usage of satellite photography for archaeological purposes.
At best, Crichton independently reinvented a technique already well known in professional circles.
Going to Google Earth, which uses the same imagery... one finds multiple similiar sites in the general area, as well as the remains of roads. One also finds current roads, and recently logged areas, like this one (just a kilometer to the west of your site).
Zooming out shows even more of the same type of site scattered across an large area (roughly 12 km on a side). (As well as clear indications of even more such sites in the area(s) adjacent that are only available in lower res.)
A few kilometers to the southwest, one comes upon a town clearly surrounded by many such sites.
Conclusion: Your site is almost certainly the remmnants of a logging operation or field clearing.
Did you ever see the movie "The Core"? It would be something like that, except less lame and far more problematic to fix. (Most likely whatever method you used to tap the energy from the core could simply be reversed, since electric motors are all capable of being electric generators and vice versa, so you wouldn't have to mount an exciting manned expedition deep into the Earth's mantle to fix it ala The Core. But, that would require that you supply even more energy than you've been taking out. Imagine if, when we ran out of oil, we not only had to find an alternative fuel source but had to spend it all on somehow creating new oil deposits, lest we all die from some resultant catastrophe. Where the hell are we going to get all that energy from, and why weren't we using it to begin with?)
-Forrest Cameranesi, Geek of all Trades
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"An infra red imaging device, or certain wavelengths of radar should work nicely." First, water is opaque to IR, you should know that! Second, radar is absorbed over relatively short distances in water, making it nearly impossible to resolve very far under water.