Rock Surface At Low Tide Under Ultraviolet Light, Fidalgo Head, Washington

Barnacles, algae, and other sea life seem to glow under ultraviolet light at low tide off Fidalgo Head near Anacortes, Washington. The glow is fluorescence, a type of photoluminescence, in which certain chemicals absorb light that is invisible to human eyes and emit some of it at a different wavelength that we can see. This scene was captured under black light at Sunset Beach in Washington Park.