on my way to Vegas from 41,000 feet above,I noticed large circles on the ground somewhere over the mid west,what are these.
This is how we irrigate our crops out here. The irrigation is above ground and has a fixed point and it rotates spraying water on the crops. Many years ago my sister from Chicago flew out here and though they were all missile silos!
crop circles? look up crop circles, and youll see what you saw i bet.
Probably still active crop circles from the gravity lift beam that forms them