From scampering octopuses to disco clams, marine biologists have gotten pretty good at parsing all the absurdity the ocean has to offer. Which is why we’re so delighted by the above video from the Nautilus Exploration Program, in which seasoned scientists greet the sight of a luminous purple blob with “What is that?!”

The Ocean Exploration Trust’s Nautilus research vessel has just wrapped up a trip to California’s Channel Islands, an area commonly known as the Galapagos of the North for its remote location and ecological richness. The islands are part of a national marine sanctuary, yet very little is known about the topography of the surrounding seafloor, how the region is weathering climate change, or the creatures who live there.

Case in point: the purple thing. The vessel’s cameras zoomed in on the unidentified object, which seemed to be made of two distinct pieces. But even at close range, the blob was no more willing to reveal its secrets. The researchers aboard began to throw out guesses: “It looks like an egg sac of some sort.” “I reckon its some kind of cnidarian?” “It looks like a disco ball.” “I’m stumped. I couldn’t even hazard a guess.”

While there was some dramatic tension when it seemed that a curious crab might snatch the mystery orb before the team could collect it with a vacuum tube on a robotic arm, in the end they successfully hoovered it up. The crew turned the gummy candy–looking thing over to experts at the Harvard Museum of Comparative Zoology. At the moment, their best guess is that it’s a type of knobbly, globular sea slug called a pleurobranch, but they’re still far from certain.

[h/t Smithsonian]

Header image from YouTube // EVNautilus

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