This extraterrestrial spacecraft Benthocodon jellyfish was spotted near undersea mountains. The photo is in a new book titled The Deep that features more than 200 photos of the insanely strange and beautiful denizen of our oceans. It was edited by Claire Nouvian, a French documentary filmmaker. Smithsonian has a feature on the book and a sampling of remarkable photos from it. From the Smithsonian article:
The more than 200 photographs–most taken by scientists from submersibles and ROVs, some shot for the book–show just how head-shakingly bizarre life can be. The scientists who discovered the creatures were apparently as amused as we are, giving them names such as gulper eel, droopy sea pen, squarenose helmetfish, ping-pong tree sponge, Gorgon's head and googly-eyed glass squid.
Nouvian herself made two dives in a submersible, to 3,200 feet. The first thing she noticed, she says, was that "it's very slow. You can tell that all their laws are different."