This deep-sea comb jelly (ctenophore) was spotted 900 meters under the Caribbean near St. Croix as it floated past the submersible Johnson Sea-Link. It's one of 24 photos taken by marine researchers around the world that form an exhibit at the U.S. National Academy of Sciences. Running through November, it supplements an academy symposium last week celebrating 50 years of ocean discovery.

LAURENCE MADIN/WOODS HOLE OCEANOGRAPHIC INSTITUTION