But marine scientists are concerned about the harm that could be caused. These researchers studied helmet jellyfish, using special tanks on a research vessel to simulate conditions created by ...

Laurent Ballesta (France) endures below-freezing dives to reveal the diversity of life beneath Antarctica’s ice. Deep below the ice, a helmet jellyfish pulses by Laurent. Exposure to direct sunlight ...

A Periphylla periphylla, or deep-sea helmet jellyfish, pictured colliding with the seafloor after it was startled by the bright lights from the submersible. These jellyfish undertake a daily ...