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Comment by cube13 | Hacker News Reader

>This has come up in the past on HN. As I understand it the newspaper story is bull.

Pretty much. The same effect that causes stars to twinkle limits the resolution of space-based spy satellites imagery of the ground.

http://en.wikipedia.org/wiki/Astronomical_seeing

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That's for distant stars though, isn't it? I mean, just with Google Maps you can see the mirrors on a car. Newsprint isn't that much of a step up.

Google Maps uses aerial photography from planes for the high-resolution layers of their maps, not satellite imagery.

Huh, interesting! I never knew that. So then I'll need to ask my father about what he was told again. Maybe something got misinterpreted along the way.

It probably was that you can see newsprint, not read it.

All of the detailed views in Google Maps are actually aerial photography rather than satellite images. Much easier to get that kind of detail from 1500ft.

While it's true that the stars are very distant, the only atmosphere that the light passes through is same atmosphere the satellites have to peer through (resulting in the same amount of distortion)

Hm, but with angles, distance matters to right? Bending light 10 degrees will mean a much bigger difference light-years away than a couple hundred miles away. That said, I could easily be missing something...

The light isn't being bent light-years away. It is being bent at the beginning of the atmosphere, resulting in the same degree of bending as the satellite has to deal with.

Not just "seeing" (atmospheric turbulence), but also diffraction.

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