You can leave a message two ways: Download the iPhone app and record it (for up to 30 seconds). Don't have an iPhone? You can borrow one from the project's home base at Eakins Oval (24th Street and the Parkway). Or you could record a message on the project's website (openairphilly.net).
The message can be whatever you want it to be: a shoutout to your girls, the Eagles fight song, an inspirational quote, your favorite "knock-knock" joke.
The messages are put in order on a first-come, first-served basis, with priority given to message-senders who are on the Parkway. If you're there when your message is put in the air, the lights will move to your exact location (thank you, GPS) so they are creating the pattern above you.
Each message also gets its own website, complete with a 3-D simulation of what your design looks like and, if it's selected, photos of the actual light design, so the project lives on even after it's over.
"Open Air" is the Mexican-Canadian Lozano-Hemmer's first major project in the United States, despite putting on large-scale projects around the world for more than two decades.
One of the inspirations for this project, Lozano-Hemmer said, came from Philadelphians' love and pride in, to put it kindly, their First Amendment rights.
"When people are given the responsibility of introducing content, sure, you get a lot of shout-outs and marriage proposals and poems and kids, but you also get really inspirational stuff," Lozano-Hemmer said. "In the age of self-expression and [the Internet], people are understanding that they have a voice, that they count."
That means even the morons get a voice, too. Lozano-Hemmer doesn't believe in censoring the messages people send, but, as he pointed out, he's also a dad, so if a message has inappropriate content in it, a function on the website allows participants to flag it as such, decreasing the chance that it will be presented.
Although he has lofty ideals, Lozano-Hemmer also understands that his project is about entertainment and that getting people out on to the Parkway at night is just as important as his own message.
"The Parkway at night was a non-place," said Penny Balkin Bach, the executive director of the Association for Public Art, who commissioned the work three years ago and is co-presenting "Open Air" with the Live Arts Festival and the DesignPhiladelphia Festival. The Parkway was designed for the people, but has essentially been used as a glorified highway. The goal with "Open Air" was to rethink public space so it was truly of the public.
With any large-scale project, controversy abounds. How will the lights affect migratory birds that are in the middle of their season? How much energy does the project use? How much light pollution does it spill into our city?
When asked about these issues, Lozano-Hemmer explained how he's tried to offset the environmental impact of his project. He is working with ornithologists and the Pennsylvania Audubon to mitigate the impact on birds. He's bought carbon credits to offset the power he uses. He said that the energy needed to power the 24 searchlights is equivalent to that used in one Eagles game.
Such concerns are par for the course with a project on this scale. "I say we specialize in bad ideas. No one has really done it because the logistics, the technology, the financing, the setup, the panoramic is so far-reaching, that anyone who is healthy says, 'You know, what? No,' " Lozano-Hemmer said.
Good thing for Philadelphia Lozano-Hemmer is a little bit crazy.
Eakins Oval Information Outpost, 24th and the Benjamin Franklin Parkway. Information center open 7:30-11 p.m., light show from 8-11 p.m., Thursday to Oct. 14, free, openairphilly.net.
Contact Molly Eichel at email@example.com or 215-854-5909. Follow her on Twitter @mollyeichel.