How to Take the Coordinate of a Structure from Google Earth

When you are doing research on various sites around the world, you want to get the most accurate coordinates you can. However, in talking with many people, it’s apparent that some do not know the proper way to do this.

I will show you a classic example, the Pyramid of Khufu from the Giza Complex in Cairo, Egypt. Here is a screenshot from Google Earth:

Pyramid of Khufu, Giza Complex, Cairo, Egypt
Pyramid of Khufu, Giza Complex, Cairo, Egypt

A lot of people would take the coordinate of the apex of the pyramid. However, that would not be correct. This is because the satellite was not directly above (over the center) when the image was taken. Therefore, the apex of the pyramid is off center. However, the solution is very simple. Don’t use the apex.

Have a look at this screenshot.

Take the coordinate from the center of the base
Take the coordinate from the center of the base

Instead, you want to take the coordinate of the center of the structure at the base, not the apex or in the case of a building, not a point on the roof.

If you follow this rule, the coordinates will not change as Google Earth updates its satellite imagery.

 

Comments

  1. says

    Thanks Rodney, that’s helped to clarify matters. Something else I’m not clear about is working out the distance between the gridlines. I know the main distance is 7.5 nautical miles, however what other distances can I use when operating the software? Can I input any figure for the distance, or does it have to be a specific number?
    Regards

    Stuart
    UK

  2. Rod Maupin says

    The grid is infinite, so there are jillions of points everywhere. However, Bruce Cathie initially found that the 30′ and 7.5′ grid resolutions (spacing) where the main ones to work with.

    When he and I reached the point where we were able to plot the grid, we found that the 6′ and 1′ resolutions were also very important.

    We have the capability in the software where you can enter your own resolution (spacing). The requirement is that the number you enter must be a harmonic of 360 degrees, meaning it has to go into 360 an even number of times with no remainder (nothing left over).

    To enter your own resolution, just go into the Settings menu, Map tab and click the Add button next to the Grid Resolutions list box.

    Rod

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