Smoke rings are being seen in a new light. Doughnut-shaped structures called vortex rings are sometimes seen swirling through fluids. Smokers can form them with their mouths, volcanoes can spit them ...

A group of hikers look at one of the smoke rings Europe's most active volcano, Mount Etna, is blowing scores of ethereal "vortex rings" every day from a single vent located in one of its most active ...

Dozens of circular loops made from smoke and volcanic gas are rising from a peculiar vent on Mount Etna every day. When you purchase through links on our site, we may earn an affiliate commission.