'Like the end of the world' - Mystery over bizarre swirl in Irish skies solved

Irish people were left scratching their heads on Monday evening after a bizarre blue swirl appeared in our skies.

The odd illumination was also visible in other parts of the world with UK media also reacting but there is an explanation. 

Cathal Nolan from Ireland's Weather Channel was one of the first to take to social media with a reason behind the blue swirl. 

He said: So this was visible in our skies tonight. Supposedly this giant swirl is the venting of excess fuel from one of [Elon] Musk’s rockets on its passage through the upper atmosphere. What are your thoughts on this kind of activity in our skies?"

Followers were quick to vent about the oddity and the likely impact on the planet. One person wrote: "It's getting beyond a joke. We recycle all we can, fined if we don't and the likes of money bags Musk able to destroy our planet as he pleases."

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Along the same lines, another woman said: "What goes up must come down and God only knows what chemicals are in that concoction."

A comment on a separate post said the light in the sky was "like something from the end of the world."

Musk's Falcon 9 rocket had lifted off just before 6pm Irish time on Monday on what the BBC has reported was "a classified US government mission."

Before the Falcon 9 returns to Earth, it ejects leftover fuel, which freezes instantly due to the altitude. The spiral shape is caused by the rockets movement as it descends. Light reflects off the frozen fuel to make it visible from Earth.