PREVIEW

BY MARK WORGAN

A mysterious “golden orb” discovered deep on the ocean floor off Alaska has finally been identified by scientists, more than two years after it was first found.

The unusual object was found in 2023 during a US National Oceanic and Atmospheric Administration (NOAA) expedition at a depth of around 3,250m (just over two miles) in the Gulf of Alaska.

Researchers have now concluded that the golden mass is the remains of tissue from a giant deep-sea anemone, Relicanthus daphneae, specifically the part that once attached the creature to a rock.

The discovery was made during a mission aboard the NOAA Ship Okeanos Explorer, when a remotely operated vehicle encountered a strange, dome-shaped object with a small opening, fixed to a rocky outcrop.

At the time, scientists were unsure what they had found, with suggestions ranging from an egg case to a sponge.

The object was collected using a suction sampler and sent to the Smithsonian National Museum of Natural History for further study.

What followed was a lengthy and complex investigation involving multiple scientific disciplines.

“We work on hundreds of different samples and I suspected that our routine processes would clarify the mystery,” explains Allen Collins, Ph.D, zoologist and director of NOAA Fisheries’ National Systematics Laboratory, which is physically located within the Smithsonian National Museum of Natural History. “But this turned into a special case that required focused efforts and expertise of several different individuals. This was a complex mystery that required morphological, genetic, deep-sea and bioinformatics expertise to solve.”

Initial analysis suggested the object was made of fibrous material and contained stinging cells typical of cnidarians, a group that includes corals and anemones. However, early DNA testing proved inconclusive.

Scientists then carried out more detailed genetic sequencing, which revealed a strong match to the giant deep-sea anemone species.

Comparisons with a similar specimen collected in 2021 confirmed the identification.

The finding brings an end to speculation surrounding the “golden orb”, which had drawn widespread curiosity online.

“So often in deep ocean exploration, we find these captivating mysteries, like the ‘golden orb’. With advanced techniques like DNA sequencing, we are able to solve more and more of them," said CAPT William Mowitt, acting director of NOAA Ocean Exploration. “This is why we keep exploring—to unlock the secrets of the deep and better understand how the ocean and its resources can drive economic growth, strengthen our national security, and sustain our planet.”