malformalady:

It turns out that putting a certain type of plankton under stress results in one of the most stress-relieving sights on the planet, their resultant blue glow creating astral patterns on sea shores. The surreal appearance of the Maldives beach was actually down to a massive tide of bioluminescent phytoplankton called Lingulodinium polyedrum however. The tiny organisms emit light when stressed, be it by the lapping of waves, the carving action of a surf board or other, creating what looks like a network of stars.

Photo credit: hala065