Pop Quiz answer

Several days ago, I posted these two pictures with a vaguely worded question:  https://themadspaceball.wordpress.com/2013/08/09/one-of-these-things/

I promised an answer to that question and here it is:  the top picture was taken from low earth orbit (LEO), the bottom from geosynchronous (GEO) orbit.

How can one tell from just the pictures?  Two big telltales exist in them.  The bottom picture nearly shows the whole Earth’s disk.  Remember in my very first post on imaging operations, I noted the further away you are, the more you will see (using a car license plate as your focus).  Second, protruding from the upper right of the top image, there’s an arm (a robotic one).  That arm is from the international space station.  Now, the station might go as high as two hundred-sixty miles above the Earth’s surface, but that’s still LEO in our definition, right?

One other thing, note how much more like clouds the clouds appear to be in the upper image.  Remember, the closer you are to something, the more detail you can see…

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