A curious new feature on the roof of a building at 1 Hacker Way. Justin Shaffer/Facebook

If an alien civilization were to gaze upon our planet from space, what would it see? Peaceful oceans, certainly, and majestic mountain ranges, and whirls of cloud and fog ... but also, of late, something else, too: a QR code. A black-and-white sign painted on the rooftop of one of the buildings in Facebook's new Menlo Park compound -- a code that, at 42 feet by 42 feet, is big enough, apparently, to be seen fairly easily from space.

Yes. We're as confused as you are, aliens.

The code -- half earnest project and half wacky prank -- began with Mark Zuckerberg's call to Facebook employees to launch a "Space Hackathon" to decorate the firm's headquarters at 1 Hacker Way. Mark Pike, who works on Facebook's intellectual property team, replied to Zuck's request, "Hack yeah! I'd like to paint a gigantic QR code somewhere so we can RickRoll online maps, or point people to our careers site, or send them to a 'Clarissa Explains it All' GeoCities Page."

By the end of the day, Pike says, his "hack yeah!" comment had received nearly 50 Likes. "I still wasn't sure if people were seriously interested," though, "so I started a Group. When over 100 people joined, it was game on."

"Game," in this case, being rooftop QR-ing. As Pike tells the rest of it,

At Hackathon 29, a couple dozen engineers, designers, and members of our operations team climbed up on the roof armed with chalk, twine, paint rollers, a few drums full of black paint, and some cold beer. Some engineers in the crowd determined the optimal orientation of the grid, consulting satellite print-outs and knowledge of local flight paths. Meanwhile, a few of us got to work chalking out a 42' square with 2' pixels. After we triple-checked the layout, we started putting down paint and hoping we didn't mess anything up. I felt like a digital Tom Sawyer convincing folks to come up to the roof to paint this funny project -- instead of whitewashing a fence, we were laying down a QR code.

So, yes. Facebook's isn't the first see-it-from-above QR code; there's a cottage industry that works to put QR codes on roofs so that they can be archived by Google Earth and displayed on Google Maps. But the Menlo Park code -- which links, at the moment, to a "coming soon" page -- is probably the most high-profile of the world's satellite-scannable-and-Internet-linkable designs. If you happen not to be a fan of QR codes, you could read Facebook's version as: a waste of employees' time and energy/unnecessary publicity for a bad technology/an omen of impending apocalypse. But you could also read the code as a rooftop reminder of the youthfulness (black paint! cold beer!) that drives one of the most powerful companies in the world. And of the fact that "The Hacker Way" is Facebook's culture as much as it is its marketing message.

As Mark Pike might say... Umm... "Hack yeah!"

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