The North Fort Worth Historical Society will have a birthday party on Tuesday for its famous household fixture — a lightbulb that has burned continuously since Sept. 21, 1908.

The bulb was first illuminated when a stagehand at a local opera house flicked a switch and posted a sign that the light over a stage entrance was not be turned off.

“We have no idea why it has lasted so long. That is the wonderful mystery of it,” said Sarah Biles, the administrator of the museum where the bulb burns, complete with its own independent power supply.

The Texas bulb is about 40 watts and made of thick glass that houses a sturdy carbon filament.

Despite having lasted 96 years so far, the Texas lightbulb does not hold the record for the longest continuously burning bulb in the world.

According to the Guinness Book of World Records, that honor goes to a some 4 watt bulb that has been burning at a firehouse in Livermore, California, since it was turned on in 1901.

More here.