I have finished my assignment on crop circles and here are my views.... I did write it a bit tongue in cheek and I have to say, that I do not say my belief is the right one!  But for the time being and in the reality I live in, that is what I came up with!  Enjoy!

What are crop circles?  Geometric designs in crop fields are no new phenomenon and have been reported for many years.  The earliest report in a reputable magazine (the only one?) was in “Nature” in 1880 ⁽¹⁾, where crop circles in the English county of Surrey had been described.  An increase of this phenomenon took place since the early 1970’s and since has been noticed in many countries all over the world. ⁽²⁾

But are they man-made, a natural phenomenon or as some people even suggests, extra-terrestrial forces at work??  From the internet search I have conducted it seems that it is still mystery.  There are several theories and hypotheses of how they are created, but all are still theories… Some more fantastic than others, but none have provided enough evidence to convince me of any of the theories.

One thing that did strike me as I was struggling through a myriad of sites was the amount of sites with a distinct “commercial flavour”!  I mean, how reputable can a site be , when the first thing you notice are pop-up menus with advertisements of books on crop circles, shops that sell crop circle paraphernalia and requests for donations for “crop circle research”? The impression I got from many sites was definitely not ‘scientific’.  They seemed either to be a personal opinion of someone obsessed with crop circles (the “research” being no more than anecdotal), or someone out to make money out of people obsessed with crop circles or some New Age healers, spiritualist or something of that sort trying to convince people of some aliens trying to communicate with us mortals on earth (and make a buck or two along the way…)!  Made me rather think of the “support group for people that had been abducted by aliens” that exists in the United States of America…

To me, with my limited knowledge of physics, the best scientific explanation for the phenomenon was given by the Plasma theory.  The plasma vortex theory was first postulated by meteorologist Terence Meaden but later adapted to the plasma theory by John Burke and William Levengood. ^{(3, 4)}  Research conducted by this team of biophysicist has come up with a few explanations of why they think that plasma is the active force behind “authentic” crop circles. They claim to have studied and analyzed plant samples from more than 300 crop circle formations from 5 countries around the world.  Patterns of physical alterations in the plants have been found for the crop formation samples, but not the control samples.   Further, these physical alterations in the tissue of the plants inside a crop circle have apparently not been found in known man-made (hoaxed) crop circles.

As I understand it, they postulate that plasma (“…a plasma is an electrically conductive collection of charged particles that responds collectively to electromagnetic forces. Plasma typically takes the form of neutral gas-like clouds or charged ion beams, but may also include dust and grains (called dusty plasma). They are typically formed by heating and ionizing a gas, stripping electrons away from atoms, thereby enabling the positive and negative charges to move freely.”) (http://en.wikipedia.org/wiki/Plasma_Physics) ⁽⁵⁾ is drawn to the earth from the ionosphere ⁽⁶⁾ by a strong electro-magnetic field.  These electro-magnetic-fields can be caused by water percolating from chalk and limestone aquifers. ⁽³⁾ Plasma reacts when traveling through a magnetic field by moving in a spiral and emitting microwaves in the process. ⁽³⁾  Thus, if plasma could reach the earth, it would explain the holes blown from the inside out in growth nodes and the elongation of growth nodes in plants inside a crop formation. ⁽³⁾  However, they cannot quite explain the shapes of crop formations!

Other explanations I have come across on the internet are however even less plausible and mostly not researchable.  One was given by a South African sangoma, Vusamazulu Credo Mutwa, only as “the writing of the gods”. ⁽⁷⁾  Another explanation given was that crop circles had similar properties to liquid crystals and that this could explain the mechanical failure of cameras, cell phones etc. in crop formations, but their research had not produced consistent results. ^{(8, 9)}

The more reputable sites I did visit like the BBC ⁽¹⁰⁾ and Wikipedia gave little credit to the research that has been done to date.  I must admit that I am very skeptical myself and the religious fervour with which some people defend the alien hypothesis undermines the scientific credibility of these reports even further, which reduces the chance that any serious research will be done to try and solve the “mystery”. To me they are a mysterious form of art, nothing more.

References:

1. Andreas Muller. Crop Circles [Internet]. Kornkreis Forschung in Deutschland. [cited 2006 May 6] Available from: http://www.kornkreise-forschung.de/
2. Wikipedia contributors. Crop circle [Internet]. Wikipedia, The Free Encyclopedia; 2006 May 2, 14:12 UTC [cited 2006 May 6]. Available from: http://en.wikipedia.org/w/index.php?title=Crop_circle&oldid=51207130.
3. John Burke. Crop circle formation [Internet]. Physics of crop formation. 1998 [cited 6 May 2006]. Available at:  http://www.bltresearch.com/physics.html 
4. Levengood W, Burke J. 1995. Semi-Molten Meteoric Iron Associated with a Crop Formation. Journal of Scientific Exploration 9 (2): 191-199
5. Wikipedia contributors. Plasma (physics) [Internet]. Wikipedia, The Free Encyclopedia; 2006 May 6, 21:58 UTC [cited 2006 May 8]. Available from: http://en.wikipedia.org/w/index.php?title=Plasma_%28physics%29&oldid=51888274.
6. Wikipedia contributors. Ionosphere [Internet]. Wikipedia, The Free Encyclopedia; 2006 Apr 26, 03:39 UTC [cited 2006 May 6]. Available from: http://en.wikipedia.org/w/index.php?title=Ionosphere&oldid=50200652.
7. Andreas Muller. Crop circle explanations [Internet]. 2006 [cited 2006 May 6] Available from: http://www.kornkreise-forschung.de/textCredoMutwa.htm
8. Hein S, Russel R. 2002. Electromagnetic and Crystalline Properties of Crop Formations. Unpublished.  Available from: http://www.mountbaldy.com/crop/
9. Hein S, Russel R. 2000. Electromagnetic Anomalies and Scale-Free Networks in British Crop Formations. Unpublished.  Available from: http://www.mountbaldy.com/crop/
10. BBC editors. Crop Circles [Internet]. [cited 2006 May 6] Available from: http://www.bbc.co.uk/science/space/life/aliens/cropcircles/index.shtml and http://www.bbc.co.uk/dna/h2g2/A724204