Jellyfish are known for drifting to and fro at the whim of ocean currents—but not all species are so passive. The millions of golden jellyfish that pack Palau’s Jellyfish Lake spend much of their lives on the move during a daily migration that follows the sun’s arc across the sky.

Before sunrise, the jellies cluster along the saltwater lake’s western shore. Each morning around 6, when dawn brightens the eastern sky, they begin to swim toward the light. Pumping water through their bells, these jellyfish use a type of jet propulsion to follow the sunlight until they nearly reach the eastern shore—stopping just short of the shadows caused by lakeside trees.

Sunlight is plentiful on this remote Pacific island, which is a