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Solar Beacon will bejewel Golden Gate Bridge through September

An art installation called Solar Beacon, mounted atop the Golden Gate Bridge towers in May by UC Berkeley space scientists, has been given a one-month extension and will remain operative through September, allowing Bay Area residents to schedule flashes of light from the movable mirrors.

solar beacon

“Possibly the coolest public arts project ever,” one viewer commented.

“So cool! It should be left on the Golden Gate Bridge permanently!” another wrote.

The “cool” project they’re referring to is Solar Beacon – a UC Berkeley art installation consisting of two sets of mirrors attached to the tops of the Golden Gate Bridge towers.

Since May 25, the public has been able to catch daily, prescheduled light shows at Crissy Field on the San Francisco waterfront or the Berkeley Marina, or go online to schedule a private viewing where the mirrors can swivel and tilt to reflect sunlight toward a specific point at a specific time. More than 700 people have scheduled flashes from the beacons within the past three months.

Though the beacons will not become permanent bridge fixtures, the installation has been given a one-month extension by the bridge’s Highway and Transportation District beyond its planned Aug. 31 end date. It now will be up through Sept. 30.

“This extends the beacon into the better weather month of September,” said John Vallerga, a UC Berkeley space scientist who proposed the installation to celebrate this year’s 75th anniversary of the bridge and designed and supervised its construction. “July and August were particularly bad this year with the fog.”

Fog didn’t deter one married couple from scheduling a light show at Ft. Baker during their wedding reception. And viewers of last Sunday’s nationwide coverage of the America’s Cup World Series race could see Solar Beacon in the background, even if they didn’t know what those bright, twinkling lights were.

“The unexpected thing was how the atmosphere distorts the lights and makes them move and bounce,” said Vallerga, who works at UC Berkeley’s Space Sciences Laboratory (SSL).

Map of Solar Beacon light show targets.

More than 700 people scheduled 1,700 light shows since Solar Beacon was installed in late May. The dots on this Google map show the sites at which the mirrors aimed.

Vallerga plans to schedule a light show tomorrow (Saturday, Sept. 1), for the benefit of those in the press box at the newly renovated California Memorial Stadium, which will host its first football game starting at noon.

He has also scheduled the beacons to shine light on the Crissy Field webcam every day between 1 and 1:10 p.m. (PDT) so that people around the world can view the art installation.

Steady improvement

Vallerga said that the beacons, called heliostats, have functioned flawlessly, aside from a few cell phone connection issues. He has performed a few software updates, however, all conducted remotely as if the heliostats were just another satellite instrument like the ones typically built at SSL.

“As the days go by, we’re making the heliostats more robust,” he said.

One update allows same-day appointments with as little as 10 minutes’ notice, enabling people to check the weather before scheduling.

Public response has been so positive that Vallerga is looking for a Bay Area location in which to install Solar Beacon long-term, preferably in a more accessible site to make it easier to troubleshoot problems. The site would have to be elevated and, ideally, allow sunlight to be flashed over a large part of the area, perhaps even into Napa and Sonoma counties.

He and London-based artist Liliane Lijn also have another art installation called Solar Hills that they would like to site in the area: five prism heliostats that break sunlight into rainbow colors.

Collaborating at UC Berkeley with Vallerga and Lijn are astrophysicist Pat Jelinsky; Laura Peticolas, director of the SSL’s Center for Science Education; detector scientists Jason McPhate and Adrian Martin; mechanical engineers Greg Dalton, Joe Tedesco, Chris Scholz and Greg Johnson; system administrator Robert Lettieri; and science educators Ruth Paglierani, Dan Zevin and Kyle Fricke.