Last weekend, a rare event was captured on camera at Italy's Mount Etna, the world's most active stratovolcano. The Sicilian volcano has been seen erupting rare, almost perfectly circular, volcanic vortex bubbles. At some points it appeared pink against the sky.
Giuseppe Barbagallo, a member of the South Etna Alpine Guides Group, told Reuters that a new crater had formed along the volcano in the past week or so. Barbagallo said the crater has a “perfectly circular mouth,” which helps form a nearly perfect circular ring of gas and vapor. According to Reuters, because of this event, many locals now refer to Etna as the “Lady of the Ring.”
“This is a special phenomenon,” they said. “We don’t see something like this every day.”
A study published last year in Scientific Reports found the ring dates back to as early as 1724. The exact physical conditions that allow volcanic vortex rings to form are unknown, the paper said. After creating model simulations, the scientists learned that the formation of the ring “requires a combination of rapid outgassing from gas bubbles at the top of the magma conduit and regularity in the shape of the vents.”
Boris Behncke, a volcanologist at the National Institute of Geophysics and Volcanology in Catania, told local news outlets that Etna produces more volcanic vortex rings than any other volcano on Earth.
“The Bocca Nuova crater has emitted thousands of rings and this continues,” Behncke said, according to a translation.
Behnke said on Twitter last week that a ring began forming in the crater on the evening of April 2 and that the volcano was erupting.unprecedented quantities“He said the next day, “This is a phenomenon that has never been seen before.”
“Someone said, ‘Perhaps there has been so much bad news lately that Etna simply decided to do something beautiful,’” he said on Twitter.
Etna is one of the most active volcanoes, with its last significant activity recorded last December, according to the Smithsonian's National Museum of Natural History's Global Volcanoes Program. This activity was recorded from December 20 to 26, when “light gray ash emissions increased from Bocca Nuova Crater.” The monitoring program said two crater eruptions produced ash plumes.