Are lighthouses lit during daylight hours?
No. Lighthouses are not lit in daylight hours, because a lighthouse light is like a giant magnifying glass made up of usually hundreds of prisms. If the light was on in daylight hours the magnified beam of light is capable of focusing the sunlight just like you can do with a hand-held magnifying glass. This laser beam of light could easily ignite dry vegetation as the light sweeps over the land.
