Electromagnetic fields cause fluorescent bulbs to glow
February 3, 2008 @ 8:07 pm
Here’s an interesting photo from Matthew Wahl’s Flickr showing the glow from fluorescent tubes as a direct result of the electromagnetic field surrounding overhead power lines. The fluorescent tubes are not plugged in to any power source.

Keep in mind that the bulbs do not necessarily glow that bright on their own. Many of the images taken of bulbs in these scenarios are long exposures. However, the bulbs do glow enough to see with the naked eye, so the awe in seeing this occurrence will surely still be there if you were to try this for yourself.

Photo: Peter DibdinRichard Box, an artist-in-residence at Bristol University’s physics department, was one of the first people to discover the phenomenon. He describes it below:A fluorescent tube glows when an electrical voltage is set up across it. The electric field set up inside the tube excites atoms of mercury gas, making them emit ultraviolet light. This invisible light strikes the phosphor coating on the glass tube, making it glow. Because powerlines are typically 400,000 volts, and Earth is at an electrical potential voltage of zero volts, pylons create electric fields between the cables they carry and the ground.Box denies that he aimed to draw attention to the potential dangers of powerlines, ‘For me, it was just the amazement of taking something that’s invisible and making it visible,’ he says. ‘When it worked, I thought: ‘This is amazing.’’

original article here http://www.doobybrain.com/2008/02/03/electromagnetic-fields-cause-fluorescent-bulbs-to-glow/