For discussions of everything that might be classed as ‘paranormal‘ - i.e. not currently accepted by our modern scientific paradigm.
However, I am not convinced they are made by aliens. I just cannot think how they would be made? By lasers? From high above from a template? But why have there been crop circle before all our modern technique, or have there?
It must be from a hovering crafts, like a helicopter, not an aeroplane. Some - many - seem too complicated to have been made just by boards.
The occasional imperfections could have come about when the crop grew a bit again? You never know who took the photos and when, let alone why?