OK of course they are not alien, but these crop circles and other agricultural designs, found in a random Google search, are pretty amazing. And they have helped a lot of social media posts go viral.
And they do lead you to wonder how they were made! Well, we can tell you with absolute certainty that the last image was created by NVIDIA Corporation last year in a field near Salinas, California to show its K1 processor technology. As for the rest…?