I will repeat what Q.E.D. stated, and say that it is absurdly unlikely, bordering on the impossible, that any crop circle, seen anywhere, can be cinsidered “authentic”, meaning a creation, for whatever reason, by extraterrestrials.
Radiation? Iron glaze? Growth rate slowed? Plant DND altered? Glowing mineral nearby? Stange sounds heard that night?
Fine, I’ll believe it the very second you show some proof. Lekatt, having books in Amazon isn’t proof- they have books on The X-Men, astrology, and the use of civet cat gallbladder as an aphrodesiac.
Crop circles are fakes. They’re made for fun, for publicity, for pay, out of sheer boredom, as an intentional hoax or for a movie.
If such indicia were indeed made by some space aliens, why circles in grain fields? I’ve never heard of a circle in a golf course, or on the White House lawn, or stamped in the snow.
No “alien” has ever burned a circle into a Wal-Mart parking lot, or melted one into Mendenhall Glacier. The circles always involve just bending the grass over- it’s never cut up and hauled off (because that’s too much work for the hoaxters) or burned (because that moves from pranking into outright vandalism, it’s harder to hide the process in the dark, and foresnic analysis can detect the fuels used.)
The circles, large as they are, are always confined to one field- wouldn’t aliens have the technology to make an ideogram that covers, say, most of Kansas? There’s areas where grain fields stretch for hundreds of miles, yet the largest circles ever made are only a few hundred yards at best.
Nope, sorry. Every crop circle was made by human hands for human purposes.