Scientists exploring deepwater habitats off the coast of Alaska came across a "confounding" sight while operating a remote deep-sea diving vessel.
The vessel, part of NOAA’s 2023 Seascape Alaska Expedition, was "gliding over a rocky outcrop" at about two miles below the surface on Aug. 30 when it found what one videographer initially called a yellow hat, according to NOAA.
Video from NOAA shows the vessel’s hand carefully "tickle" the shiny object before picking it up and sucking it into a vacuum-like tube.
"This smooth, gold, dome-shaped specimen, a little over 10 centimeters (4 inches) in diameter, was tightly adhered to a rock," NOAA explained. "A small hole or tear near its base revealed a similarly colored interior. As cameras zoomed in, scientists were stumped as to its identification, with initial thoughts ranging from a dead sponge attachment, to coral, to an egg casing."
This unidentified specimen, seen in situ on a rocky outcropping at a depth of about 3,300 meters (2 miles), was seen on August 30, 2023, during Dive 07 of the Seascape Alaska 5: Gulf of Alaska Remotely Operated Vehicle Exploration and Mapping expedition. Image courtesy of NOAA Ocean Exploration, Seascape Alaska
"Isn’t the deep sea so delightfully strange?" said NOAA Ocean Exploration’s Sam Candio, expedition coordinator for the ongoing Seascape Alaska 5 mission. "While we were able to collect the 'golden orb' and bring it onto the ship, we still are not able to identify it beyond the fact that it is biological in origin."
Candio said scientists will learn more about it in a lab setting with more sophisticated tools than what’s currently available on the research ship.
"While somewhat humbling to be stumped by this finding, it serves as a reminder of how little we know about our own planet and how much is left to learn and appreciate about our ocean," Candio said.