Mount Etna in Sicily has been blowing smoke rings from its top. This may sound like something from ancient mythology, with a legendary dragon breathing out from its lair, but these are volcanic rings of gas and water vapour being pumped out from a newly formed crater near the top of the volcano.
The phenomenon is called vortex rings, made up of hot gases and water vapour shot out from a narrow vent in the volcano. As molten rock — magma — rumbles below, every so often a bubble at the top of it bursts and shoots a blast of gas at high speed up through the vent. The circles are created from the round-shaped vent and as hot gas rolls up its sides and
