There are probably no satellites that can read license plates from orbit.
The military/intellegence agencies probably have the capability of a resolution (smallest object clearly "seen") of 10 centimeters or so - maybe a bit better, but you need a resolution of a centimeter or two to really ready a plate number.... IF !!IF!! the plate is at nadir (that is, DIRECTLY below the satellite).
To read a plate, you have to be looking sideways, which means that the distance between the satellite and the plate is much longer, hence the resolution is much less.
You would need a satellite with near millimeter resolution to see a plate number. Sorry, even the NSA doesn't have that.
CJSF
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