One of nature's coolest visual phenomenons is the sight of brightly glowing water under starry skies. This bioluminescence is caused by phytoplankton giving off a brilliant blue glow and can be seen in oceans around the world. The best theory for why bioluminescence occurs is that the lights acts as a warning to potential predators.
Phytoplankton wash ashore in the Lakshadweep islands off the coast of India.
Spots of light line the shore on Vaadhoo Island in the Maldives.
The water lights up behind aircraft carrier U.S.S. Carl Vinson. Pilots sometimes use bioluminescence left in the wake of aircraft carriers to trace their way back after night missions.
Waves light up during a red tide event in Leucadia, CA in 2011.
A beach in the Florida Everglades.
An island beach in the Maldives.
The beach in Leucadia, CA.