Accuracy of Google Earth?

OK. Google Earth pretends to go to 0º00'00.01", which is to say one hundredth of one second of one degree. This is equal to (and correct me if I'm wrong) 30.87cm.


1º = 60 nautical miles so therefore 0º01'=1 nautical mile


1 nautical mile = 1852m


therfore the accuracy proclaimed by Google Earth is 1852/60/100 which equals 30.87cm


Is Google Earth software really that accurate?

Accuracy of Google Earth?
My maths work out the same as yours, 0°00'00.01" is indeed 30.87cm, assuming that 1 nautical mile = 1,852m. Which is an approximate assumption. However the possible variance between the assumption and the reallity is known to be negligeable.


Thus 0°00'00.01" can be accepted as 31cm or there abouts.
Reply:I think so, but I think it refers to the precision to which it moves (left, right, up, down), and not the accuracy of the picture.
Reply:unsure, but the satellite images a well out of date in some areas (6/7 years)
Reply:Their picture of my back garden is about ten years out of date!
Reply:Wow!... I don't know the answer, but the piccies of our farm look pretty darn good!!
Reply:no way...i mean about 8 years there were boat houses there already...but on google earth there r no boat houses..its like 9-10 years late...but i have to say the details in the photo are accurate.
Reply:No
Reply:dam close
Reply:yes
Reply:I don't know that they're accurate to within 30 cm, but they are to within a few meters. Case in point: zoom in on Quito, Ecuador (actually a suburb or two north). Look for Mitad del Mundo, the monument marking the exact point they USED to believe was the equator. Turns out they were 240 m off (see Wikipedia below). Using the "ruler" tool, I drew a line 240 m long from the monument, and it ended very close to 0º00'00.00.





So, yeah, I think they're using pretty accurate GPS to determine the coordinates. More accurate than the actual physical lines us humans have drawn. (For example, it looks like the true 49th parallel runs just off the "official" border between US-Canada.)