QUEST Lab: Bridge Thermometer

The roadway across the Golden Gate Bridge rises and falls as much as 16 feet depending on the temperature. When the sun hits the bridge, the metal expands and the bridge cables stretch. As the fog rolls in, the cables contract and the bridge goes up. Curators from the Outdoor Exploratorium in San Francisco have set up a scope two miles away so you can see how the bridge is moving up or down depending on the weather.