So are the aliens really coming ? It may dissappoint you but unfortunately this does not seem like an alien phenomenon. No credible sources have suggested that it has been created out of alien technology and unlike Area 51, the government this time is not accused of any cover up. Sorry but No Men in Blacks this time !
Google trend data suggests that these structures have definately grabbed a lot of attention, however they still do not form any conspiracy theories unlike the crop circles of Peru. 
So then why is the internet gaga over it ? 

In the words of the renowned Nobel Laureate Richard Feynman : "the thing that does not fit is the most interesting”. Our tendency to form speculations gives rise to fiction. And we all love fiction don't we ?

While the creators of this structure seem to be silent and the internet is coming up with countless hypothesis, one must always remember the words of Carl Sagan: "extraordinary claims require extraordinary evidence"