There's no reason to think that crop circles are the work of aliens - particularly when human pranksters have already admitted to making them - but they're still mysterious... not to mention a fascinating junction point between physics and art.
Part of the reason we don't fully understand the science that goes into making crop circles is that they're so thoroughly associated in the public consciousness with extraterrestrials, UFOs, and, well, hoaxes about extraterrestrials and UFOs. Under those circumstances, it's perhaps understandable why the average scientists decide to just leave well enough alone, content with the fact that we have the broad strokes of how hoaxers go about making them without any need to invoke an extraordinary explanation like visitors from another world.
Crop circles might not inflame the public imagination today like they did back in their 1970s and 1980s heyday, back before people had come forward to admit the hoax. But if anything, the art of making crop circles has become even more advanced in the ensuing years, and the artists behind these modern circles are no more forthcoming than their predecessors in explaining just how they create the intricate patterns like the one you can see up top.
To that end, researcher Richard Taylor, who is the director of the University of Oregon's Materials Science Institute, has pondered just what goes into these modern circles. He argues that modern circle-makers probably take advantage of GPS, lasers, and microwaves, which can provide them with the sort of perfect mathematical precision that you just can't get with more traditional equipment like wooden planks or bar stools.
The microwaves are particularly interesting. Taylor argues that these could be used to make crop stalks fall over into a horizontal position and then quickly cool - this would account for the speed and efficiency of some crop circles' construction, not to mention the incredible detail on display. This accords nicely with the work of one research team, which claims to have replicated some of the intricate geometric patterns by using a handheld magnetron - which can easily be salvaged from most microwave ovens - and a 12-volt battery.
The basic point that Taylor keeps coming back to is that, while the makers of crop circles are definitely human, that doesn't mean their accomplishments are any less extraordinary. Indeed, one might argue that makes these circles even more amazing than if some aliens had made them:
"Crop-circle artists are not going to give up their secrets easily. This summer, unknown artists will venture into the countryside close to your homes and carry out their craft, safe in the knowledge that they are continuing the legacy of the most science-oriented art movement in history."
Via Physics World.