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!"

No comments and the side is already quite slow, so

[pklinken]

Here goes:

http://www.cosmosmagazine.com.nyud.net/node/1764 [nyud.net]

Re:Work underwater?

[Anonymous Coward]

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.

Re:weird building angles!

[icebike]

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.

Michael Crichton ripped this idea off.

[DerekLyons]

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.

It's laugably easy! To make mistakes.

[DerekLyons]

t is actually easy to find candidates, but how about travelling to mexixo? http://maps.google.ca/maps?hl=en&ie=UTF8&ll=20.558767,-88.630174&spn=0.003541,0.005021&t=h&z=18&om=1 [google.ca] This could be anything, but an ancient structure is one of the possiblilities. MB

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 [google.ca] (just a kilometer to the west of your site).
 
  Zooming out [google.ca] 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 [google.ca] clearly surrounded by many such sites.
 
Conclusion: Your site is almost certainly the remmnants of a logging operation or field clearing.

Re:Google must be a treasure trove...

[Pfhorrest]

Of course even if we found a way to tap those flows, corporations, governments and religions would all try to claim control of it, or abolish it as contrary to their plans.

Not to mention the wise old adage, TANSTAAFL: There Ain't No Such Thing As A Free Lunch. If you could somehow tap energy from the Earth's magnetic fields, the Earth's magnetic fields would weaken. And unlike most other power sources on Earth (excepting nuclear), the planet's magnetism is not solar-powered, and the Earth will not recharge its magnetic field naturally. The Earth's magnetosphere is responsible for many important life-sustaining functions, such as protecting us all, in non-polar regions at least, from the more harmful bits of radiation coming from the sun. (I suppose you might try to harvest the deflected radiation which causes auroras at the poles, and so indirectly take advantage of the magnetosphere without depleting it).

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?)

Re:Work underwater?

[rmessenger]

"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.