A smoke ring formed in the sky after a transformer explosion in Branford on Thursday and the mysterious looking formation is called smoke vortex ring.
Smoke vortices form when there is a blast through a circular structure, according to a report from NBC News.
[HAR] Photos: Smoke Ring Forms in Branford
NBC Connecticut meteorologist Ryan Hanrahan explained smoke vortex rings on his Facebook page, saying you can see these after explosions in volcanoes or a smoke stack and you saw them in Branford because a transformer is shaped like a cylinder.
For more videos of smoke vortex rings, check out NBC News’ page.