The state uses satellites to locate basic farmland in the countryside, to determine the size of the farmer's home base, all of which can be accurate to the decimeter. Including your yard do grow what plants, can be photographed.
Because the satellite through the camera to obtain the Earth's geomorphological facilities photographs, including basic farmland and residential base of the photographs, he is after the field measurements of the shooting, and did not go through any modification or forgery, so the accuracy of the photographs taken is very high.