Ghostly Mussels

A bed of mussels make up a living sea floor at the base of Giggenbach, a recently discovered volcano located near the island of Tonga in the South Pacific Ocean.

Filtered sunlight traveling more than 300 feet from the ocean surface is responsible for the ghostly blue hue.

The discovery was made as part of an ocean voyage exploring the zone of volcanic activity in the Pacific Ocean known as the "Ring of Fire." The nearly five-month long international expedition was conducted by researchers from the Hawaii Undersea Research Laboratory, with support from the National Oceanic and Atmospheric Administration's (NOAA).

--Ker Than

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Credit: Hawaii Undersea Research Laboratory/NOAA