Stargazers have been left baffled after spotting a bizarre phenomenon that look likes oil on water - but it's in the sky.
People across Scotland took to social media on Sunday to share their snaps of the strange rainbow-coloured clouds, with some even branding it an 'alien' sighting.
Many pictures were uploaded of the clouds as they passed over Scotland and the Highlands last night, including Moray, Montrose, Aviemore, Aberlour, Turriff and Carrbridge.
Many people seemed at a loss about what they had witnessed, but it has been confirmed the sighting was actually a Nacreous cloud, formed when low-lying clouds cause ice particles to freeze and refract light.
What do you think about the sighting? Let us know in the comments...
Among the people lucky enough to capture the cloud in a photo was Dan Chilton, who then posted his stunning picture on Facebook, as the Daily Record reports.
Writing on the Scotland from the Roadside group, he said: "Strange iridescent cloud over Moray this evening. The zoomed-in iPhone camera doesn't do it justice."
Before long, the post had received a staggering 1,500 likes, as well as more than 130 comments, and other witnesses were keen to share their experiences of the cloud.
"Took the same photo from Carrbridge. Awesome to see," one said, while a second wrote: "Here above Culbokie right now. Looking towards the East."
"Wow, breathtaking indeed," third said, while another wrote: "Spotted in Aberdeen seven years ago to the day. Spooky."
"Aliens," one person simply said, while another echoed: "I don't care what anyone says, we are not alone."
Meanwhile, a fifth joked: "Superman coming for interview with Aberdeen FC."
Another commented: "What an experience, to see such a wonder with your own eyes! Thanks for sharing it with me."
The rare Nacreous cloud, also known as mother-of-pearl clouds, are brightly coloured and resemble a thin layer of oil on top of water.
Nacreous clouds require extremely low temperatures to form, and are therefore only found high up in the atmosphere. The bright colours are caused by the ice particles that form the clouds scattering light in a different way than regular clouds.
Do you have a story to sell? Get in touch with us at yourmirror@mirror.co.uk
