The appearance of black smoke rings in the sky makes many people believe this is a sign of an alien invasion.

While driving with her boyfriend through the area near Birkenshaw village, West Yorkshire, England on the afternoon of July 9, Kimberley Robinson, 22 years old, saw a black circle floating in the sky, Daily Star reported on July 13.

“It looked a bit like smoke but it was round,” Robinson said. “We’ve never seen anything like it.” This black circle looks like a giant smoke ring, but West Yorkshire fire department said there were no reports of fires in the area at the time.

Similar phenomena also occurred in the state of Missouri, USA on the evening of July 8 or Novosibirsk, central Russia in April. Russian meteorological experts confirmed that this phenomenon was not related to the weather while Missouri police said that this is a product of fireworks.

The fact that many mysterious black circles appeared in the sky around the world sparked rumors related to alien invasion. “This is like some kind of scary omen,” said a witness named Marina. “Aliens are coming to us. It’s scary,” commented social network user Andrey Ivanov.

However, experts have another explanation for this phenomenon. “Smoke vortices can be created by accident or by human intention when a wind blows smoke through a circular structure like a chimney,” said Nick Pope, who has investigated unidentified flying objects (UFOs). ) and other mysteries for the US Department of Defense to explain. “If it was intentional, it could have been the result of festive fireworks.”

Nigel Watson, a UFO expert in the UK, believes that the black circle near Birkenshaw is related to an annual event in the area. “This phenomenon was formed during cannon shots recreating historical battles in Yorkshire.”

In a video posted in 2008, a group of American men used homemade equipment to create black smoke rings in the sky during a festival in the Black Rock Desert, Nevada. These circles have a similar shape to those discovered recently.

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