I am a subscriber to Google Earth. I live in Bogota, Colombia and it seems that Google Earth hasn’t updated my area for more than 7 or 8 months. It shows a vacant lot next to my apartment. They have been building an apartment on this vacant lot for the past 7 or 8 months, yet Google Earth still shows it as vacant. What gives with Google Earth? How often should the map be updated?
Dude, I live in the United States, and my Google earth image is at least 5 years old. I think your expectations might be a little high.
Well, this still doesn’t answer my question. How often should the map be updated? 
Google Earth should be updated in realtime. But super-high resolution satellite imaging technology only exists in movies. In reality, according to the FAQ the images are taken from various satellites and aircraft from sometime in the last three years.
I don’t have a cite handy, but IIRC Google Earth was made possible when Google purchased a company that possessed the copyright to a large base of satellite pictures. I guess it’s just too expensive to update the maps regularly - after all, we’re talking about a surface of 510 million square kilometres. They certainly replace old pictures with new ones from time to time, but it will take years until a given area is updated.
There’s some bits which are a lot older than three years: search ‘m11 3ff’. The stadium you can see the foundations of was in use by 2002.
Until a few weeks ago, the images of Chicago were from 2002 and showed a few things that are no longer present, such as an empty lot near me that has been built on and the U505 submarine which has been moved indoors from outside of the Museum of Science and Industry. The current images are from 2005.
The DG layers give info on when the images were taken.
We bought our house 5 years ago as a dilapidated dump. Today, it and the land are fully restored but if I want to relive those times, Google Earth will show me the fallen down barn, random trash piles, and a large abandoned storage trailer off in the woods. I wish I lived in South America where things are updated every year or so.
If we assume that each picture covers 10sqkm (which is probably high, but let’s go with it). They would have to take and upload 1.6 pictures every second of every day to update the whole system in a year.
Doesn’t that depend on how many satellites are taking photos? Does anyone know how many satellites are mapping the earth?
The types of photos where you can see a “vacant lot” or “trailer” are usually aerial photos taken by plane, not satellite.
The best satellite photos are at 1 meter resolution. Most satellite photos have far lower resolution than that. Satellite photos are very expensive, even when you buy them from the government.
I wanted to add, I don’t know about South America, but in the U.S. aerial photos sponsored by local governments are usually never taken more than once a year, if that.
The one meter figure for satellite images, is referring to the most common publicly accessible images. Spy satellites or private satellites might have better resolution than that.
I was under the impression that all of Google Earth photos were by satellite. I can zoom out from this photo until I see the whole city of Bogota and zoom further until I can see the whole country etc etc…
If you have different types of photos, software can do amazing things with it.
Boy, have I ever been bamboozled. :rolleyes:
There is nothing wrong with that. Google Earth can let you fly off into space and then zero in on your own home. You don’t think we have a satellite that high that can take an image so fine that you can zoom it down to that level do you? That is really the heart of what Google Earth is. It takes lots of imagery sources from the whole plent and fits them together into a composite that you can view many ways from an amazingly easy interface. If they want to photograph my town with a combination of Cesna’s and CIA spy satellites, that is fine by me as long as it does what it should.