The series of wheels rolling atop the Adobe Systems headquarters in downtown San Jose is a very visible mystery.
"They move at different speeds based on the message," said Stacy Martinet of Adobe.
And for the third time in 17 years, the giant orange wheels, called a semaphore puzzle, have a message hidden in the motion.
"This is the third semaphore," said Martinet.
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It spins out a code for someone to crack, and it's likely going to take some time -- the last puzzle took more than four years to solve.
"I think the goal, if anything, is to make it meaningful for people," said Ben Rubin.
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The New York-based artist who creates these puzzles, said the semaphore is meant to be both something cool to look at, and something to figure out.
"That's been the hope from the beginning that people will see these discs up there turning, and wonder to themselves, ‘what's going on up there, is there some meaning to that?’ And it turns out, well there is,” he said.
So, if you're around, look up.
Some of the world's brightest minds will be along for the ride.
"If you solve it, you win two years of Creative Cloud membership, and bragging rights,” said Martinet. “It's pretty impressive."
Adobe says past semaphores have drawn international attention and they have no idea how long this one will take to solve.
