So does that mean these have to be genuine messages from extraterrestrials? Not necessarily ... the university results are out now, and perhaps some new graduate in computer science and astronomy decided to celebrate in a unique way!
Crop circle enthusiasts insist that these extraordinary pictograms are proof that a higher intelligence is trying to make contact with humans. Sceptics retort that, if the ETs are so clever, they ought to master email and radio broadcasts, instead of leaving cryptic clues in the corn.
I think we're all missing the point. One thing that's clear to me is that, if something or someone is making contact (and I have believed in extraterrestrial intelligence for many years) they won't use conventional communiqués.
The Harvard psychologist Professor John Mack points out that we perceive the world differently when we dream from when we're awake. Dreaming and waking are both 'real' - but we don't accept dreams as 'reality'. Maybe, Mack says, we need to be in an 'unreal' state of mind to enter the real world of aliens.
In the same way, I have always been puzzled by people who claim to be atheists because they can't accept the notion of God as an old man with a white beard, sitting on a cloud and surrounded by harpists.
I don't perceive God that way either. Michelangelo used the image on his Sistine Chapel ceiling, but I don't imagine he really thought God liked sitting on clouds. It would be too damp, for one thing.
Michelangelo was painting God for the 'real' world to see.
But to really know God, and aliens, you must follow your heart and trust in a different kind of reality - spirituality.