High above downtown San Jose, Adobe has launched a new semaphore puzzle contest to serve as the tech titan’s latest tricky optical telegraph that challenges people to crack its code.

The semaphore, atop Adobe’s Almaden Tower, is public artwork crafted by new-media artist Ben Rubin that challenges people to solve the mystery message in the ever-shifting patterns of the glowing wheels on the high-rise.

“The idea was brought to life in partnership with the San Jose Public Art Program whose mission it is to infuse art and innovation through the downtown area,” Adobe said in a blog post the company published Thursday. “As the Semaphore’s wheels turn slowly and come to rest, it transmits a message that is visible for miles (and online!)”

People who want to participate in the contest can visit Adobe’s website for more information.

The optical telegraph puzzle might be a tough mystery to unknot. Adobe’s previous San Jose Semaphore required about 4½ years to solve, the tech company said.

It’s akin to the semaphore telegraphs of centuries past, according to Adobe.

“The Semaphore is illuminated by 24,000 LED lights and has transmitted two codes since its installation in 2006,” Adobe stated in the blog post. “Now, the third code is waiting to be solved.”

There are a few key reasons — 256 reasons, actually — the new semaphore isn’t likely to be solved today — or this year.

“Each wheel of the Semaphore can assume four positions, vertical, horizontal, left-leaning diagonal, and right-leaning diagonal,” Adobe states in its blog post. “Together, the four wheels have 256 possible combinations.”

And the patterns change every 7.2 seconds, with the message being transmitted at a steady rate, according to the company.

The first message was the full text of Thomas Pynchon’s 1966 novel “The Crying of Lot 49.” It was solved in 2006 by a team of two research scientists, Mark Snesrud and Bob Mayo.

The second message was an audio file of the famed declaration from the first lunar landing by U.S. astronaut Neil Armstrong as to how he had taken “one small step for man, one giant leap for mankind.” That second puzzle was solved in 2017 by Jimmy Waters, a high school math teacher from Tennessee.

“Today, it’s easy for anyone to encrypt a message so strongly that only a government agency would have the resources needed to decode it,” said Rubin, the San Jose Semaphore artist. “Instead, I’ve had to find ways to make it challenging but still possible to decode the message.”

As an added twist, the patterns of the coded message can be jostled when jetliners zoom past the building on their way to San Jose International Airport. After the airplane turbulence settles down, the correct puzzle pattern resumes.

“The interactive art piece is a way to connect with the local and global community,” said Eric Kline, director of global workplace experience design at Adobe. “While it’s exciting when the code is cracked, an equally rewarding piece of the Semaphore is the community that forms around solving it.”

The winner receives a two-year subscription to Adobe Creative Cloud. Oh, also the bragging rights for being the new San Jose Semaphore puzzle champ.

“Most people probably don’t pay much attention to those big orange shapes slowly turning on the San Jose skyline,” Rubin said of the puzzle.

Rubin believes the artwork can be another way to help create new connections for people to downtown San Jose.

“My hope is that when people hear about the challenge and learn that these shapes are actually transmitting a message, that they’ll feel that they are ‘in the know,’” Rubin said. “They’ll feel a new connection with this piece of the city.”