Planes write out pi over the skies of San Francisco Bay Area

Many denizens of the San Francisco Bay Area and Silicon Valley noticed a long series of cloudy numbers in the skies around noon on Wednesday, September 12. No, their coffee wasn't spiked with hallucinogens.

The ephemeral event, known as Pi in the Sky, utilized five aircraft with dot-matrix skywriting technology to write out a thousand numbers of the beloved mathematical constant pi (3.14159..) at a 10,000-foot altitude. If that wasn't impressive enough, the numerals of pi written in the sky each stood nearly a quarter-mile tall, stretched for a 100-mile loop, and undoubtedly caused mass inspiration and confusion all at once.

So why did someone write out a bunch of pi numbers in the wild blue yonder? The official Facebook page for the occasion says Pi in the Sky "explores the boundaries of scale, public space, permanence, and the relationship between Earth and the physical universe. The fleeting and perpetually incomplete vision of pi's never-ending random string unwinding in the sky will create a gentle provocation to the Bay Area's seven million inhabitants."

A quick search on Flickr and YouTube reveals that many people found themselves confused by the numbers in the sky, with theories ranging from a phone number, chemtrails, secret code, and other conspiracy theories.

California artist Ishky collaborated with art and technology network Zero1 on the geeky endeavor, billed "as largest physical expression of pi ever created" and part of the 2012 Zero1 Biennial, a massive Bay Area event that celebrates the convergence of contemporary art and technology.

The skywriting kicked off in San Jose, then went over Fremont, Hayward, Oakland, Berkeley, San Francisco, San Bruno, San Mateo, Redwood City, Palo Alto, and Mountain View. The organizers specifically chose to fly over the headquarters of NASA Ames, Lawrence Livermore National Laboratory, University of California at Berkeley, Stanford University, Google, Facebook, Twitter, and Apple.